Upgrade to remove ads
MCAT 2015: Biology 2
Terms in this set (534)
Three types: Bacteria, Archaea, and Eukarya.
All organisms that can reproduce fertile offspring with one another.
Part of a trait, describes the chromosomes of an organism.
Part of a trait, describes the product of the genes that can be observed.
One form of a gene.
A gene that has multiple alleles.
The total of all alleles in a population.
A change in a population's gene pool.
The formation of a new species.
The mating of relatives, increases number of homozygous individuals in a population without changing allele frequency.
Mating of nonrelatives.
Few survivors of a crisis, allelic frequencies are not representative of the original population.
The process by which members of a species tailor their behaviors to exploit their environment.
Genetic or behavioral changes that are advantageous in the given environment.
Theory in which no evolution would occur: mutational equilibrium, large population, random mating, immigration/emigration must not change the gene pool, no selection for the fittest organism.
Can be measured by gradual random changes in the genome.
One allele may be permanently lost due to the death of all members having that allele.
The fittest organism is the one that can best survive to reproduce offspring.
Genes that are advantageous in a given environment are preferentially passed down.
Organisms best adapted to a given environment will be most likely to survive to reproductive age.
Infectious agents that have the ability to transfer genetic material.
A protein coat (virus).
A mature virus outside the host cell.
The cell that is being infected.
Usually a specific glycoprotein on the host cell membrane.
A virus that infects bacteria.
Virus commandeers the cell's synthetic machinery to replicate viral components.
What the cell uses to produce proteins.
The viral DNA is incorporated into the host genome. When the host cell replicates its DNA, the virus' DNA is replicated as well.
Pinched off pieces of host cell membrane, protects an enveloped virus from detection by the immune system.
Typically lyse a cell and cause cell death on their release.
Some single-stranded RNA viruses that are able to transcribe their RNA into double stranded RNA, done using the enzyme reverse transcriptase.
HICV (human immunodeficiency virus)
A retrovirus that attacks cells involved in the immune response.
Cells that do not have membrane bound nuclei. Split into Bacteria and Archaea.
Found in extreme environments. Unlike bacteria, the cell walls are not made from peptidoglycan.
Three Basic Shapes of Bacteria
Cocci (spherical), bacilli (rod-shaped), spirilli (spiral shaped).
Mutually beneficial relationship.
The relationship is beneficial to one organism and harmful to the other.
Not dependent on oxygen for growth and survival.
Dependent on oxygen for growth and survival.
Phospholipid bilayer that surrounds the cytosol of nearly all prokaryotes.
Phosphate group, two fatty acid chains, glycerol backbone.
Surrounds the protoplast.
Composes the cell walls of bacteria.
Long, hollow, rigid, helical cylinders made from a globular protein called flagellin. Rotate counterclockwise to propel the bacterium --> Flagellar propulsion.
Directed movement toward substances that will promote the survival and growth of the bacterium.
A type of asexual reproduction, used by bacteria.
Genetic Recombination Forms
Binary fission, conjugation, transformation, transduction.
Origin of Replication
In binary fission, the same point on the circle where two DNA polymerases begin.
Genetic recombination, involves the transfer of a plasmid.
Small circles of extragenomic DNA.
Genetic recombination, process by which bacteria incorporate DNA from the external environment into their genomes.
Genetic recombination, involves the transfer of genetic material by a virus.
The virus that mediates transduction.
Pieces of DNA that are capable of "jumping" from one place to another along the genome.
Contains all of the DNA in an animal cell, other than small amounts in the mitochondria.
A double phospholipid bilayer surrounding the nucleus.
Large holes in the nuclear envelope.
Where ribosomal RNA (rRNA) is transcribed an the subunits of the ribosomes are assembled.
Endoplasmic Reticulum (ER)
An organelle on which proteins that will be exported from the cell/sequestered in a vesicle are translated.
The area enclosed by the ER membrane.
ER near the nucleus has many ribosomes attached to it on the cytosolic side, giving it a granular appearance.
A series of flattened, membrane bound sacs whose major functions are packaging and secreting proteins.
A type of vesicle that contain hydrolytic enzymes to break down macromolecules by hydrolysis.
Programmed cell death
Tubular, functions differ according to the type of cell. Plays a role in lipid metabolism.
Cells containing predominantly fat droplets inside of smooth ER.
Vesicles in the cytosol that are involved in both lipid and protein storage. Self-replicate, involved in the production and breakdown of hydrogen peroxide.
The powerhouses of the eukaryotic cell, the site of ATP production.
Inner Membrane (Mitochondria)
A phospholipid bilayer, invaginates to form cristae. Holds the electron transport chain of aerobic respiration.
Between the inner and outer membrane of mitochondria.
Network of filaments on a cell, determines the structure and motility of the cell. Composed of microtubules, microfilaments, and intermediate filaments.
Provide a platform for transport within cells and support the shape of the cell. Hollow tubes made from the protein tubulin, a globular protein that polymerizes into long straight filaments under certain conditions.
Microtubule Organizing Center (MTOC)
Where the - end of the microtubule attaches. Microtubules grow away from the ___ at its + end. The major ____ in animal cells is the centrosome.
Function in the production of flagella and cilia, but are not necessary for microtubule production.
Flagella and Cilia
Made from microtubules, function to move fluid. The major portion of ____ contains nine pairs of microtubules that form a circle around two lone microtubules in a 9+2 arrangment.
This protein forms cross bridges to connect each outer pair of microtubules to its neighbor.
Actin filaments. Interact with myosin to cause muscle contraction. Responsible for the pinching of the cytoplasm during cytokinesis.
Maintain the cells shape, not as dynamic as microfilaments or microtubules.
A molecule that has both a polar and nonpolar portion.
A spherical structure composed of aggregated amphipathic molecules that forms in aqueous solution.
Integral or Intrinsic Proteins
Amphipathic proteins, can cross the membrane from the inside of the cell to the outside.
Fluid Mosaic Model
Membrane proteins are distributed asymmetrically throughout the membrane. Phospholipids and proteins can slide past each other, parts can move laterally but cannot separate.
Net movement of a substance from an area of high concentration to low concentration (in the absence of an electric charge, in which case the opposite can occur).
Chemical Concentration Gradient
A series of vectors pointing in the direction of lower concentration.
A series of vectors pointing in the direction that a positively charged particle will tend to move.
Addition of the chemical concentration gradient and electrical gradient.
Allows certain substances to pass through but not others.
Diffusion where molecules move through leakage channels across the membrane through random motion.
Carrier Proteins/Membrane Channels
Embedded in the cell membrane, assist molecules in moving across the membrane.
Diffusion that occurs down the electrochemical gradient of all species involved with the assistance of carrier proteins.
Movement of a compound against its electrochemical gradient. Requires expenditure of energy.
The aqueous solution of a cell's cytosol contains approximately the same concentration of particles as the aqueous solution surrounding them.
Cells that are more concentrated than their environment.
Cells that are less concentrated than their environment.
The "pulling" pressure generated by a concentration gradient, which encourages osmosis.
A property that is based on the number of particles present rather than the type of particle.
Cells use this to acquire substances from the extracellular environment. Types: phagocytosis, pinocytosis, receptor mediated cytosis.
The cell membrane protrudes outward to envelop and engulf particulate matter.
Provides a way for substances to leave the cell.
The first three stages of the life cycle of a cell: G1, S, G2.
The cell has just divided and begins to grow in size, producing new organelles and proteins. RNA synthesis and protein synthesis are highly active.
Go Phase (Cell Growth and Division)
A non-growing state distinct from interphase. Responsible for variations in length of the cell cycle between different types of cells.
The cell devotes most of its energy to DNA replication. An exact duplicate of each chromosome is created.
When mitosis occurs, division of the nucleus.
The cell prepares to divide.
The unchecked growth of cells.
Groups of similar cells that work together for a common purpose.
Cells that secrete fibrous proteins which form a molecular network that holds tissue cells in place.
A molecular network that holds tissue cells in place.
Connect animal cells: tight junctions, desmosomes, and gap junctions.
Form a watertight seal from cell to cell that can block water, ions, and other molecules from moving around and past cells. Cells joined this way can act as a complete fluid barried.
Join two cells at a single point, attach directly to the cytoskeleton of each cell. Found in tissues that normally experience a lot of stress due to sliding.
Small tunnels that connect cells, facilitating the movement of small molecules and ions between the cells.
Intracellular Second Messenger
Chemicals that activate or deactivate enzymes and/or ion channels and often create a 'cascade' of chemical reactions that amplifies the effect of the hormone.
A highly specialized cell capable of transmitting a signal from one cell to another through a combination of electrical and chemical processes.
Dendrites, cell body, axon.
A way for the nervous system to screen for the most important stimuli. Types: spatial, temporal.
Frequency of Firing
Used to help determine the intensity of a stimulus.
The site of connection between the cell body and the axon, generates an action potential in all directions, including down the axon.
Bind substances (ligands) such as neurotransmitters and hormones, and respond by triggering processes within the cell.
Open to allow ions to travel from one side of the membrane to the other, facilitating the transmission of signals.
Where differences in concentration initiate the moving of charge and thus create a voltage.
The electrical potential, or voltage, across the neuronal membrane at rest.
A pump in the neuron's membrane that functions to maintain or reestablish the chemical gradient that is lost by diffusion.
Determines the value of the resting membrane potential.
The mechanism by which a signal travels down the length of a neuron and ultimately is transferred to the next cell.
Voltage Gated Sodium Channels
Proteins that change configuration when the voltage across the membrane is disrupted, allowing Na+ to flow through the membrane for a fraction of a second.
Through the use of voltage gated sodium channels, the membrane potential reverses polarity so that it is positive on the inside and negative on the outside.
Voltage Gated Potassium Channels
Allow K+ to flow out of the cell, moving the potential back towards the negative equilibrium potential of potassium.
Through the use of voltage gated potassium channels, the membrane potential is restored to being negative on the inside and positive on the outside.
For a fraction of a second, the potential across the membrane becomes even more negative than the resting potential.
Unless the membrane completely depolarizes, no action potential is generated.
In order to create an action potential, the stimulus to the membrane must be greater than this.
A stimuli causes a depolarizing effect.
A stimuli causes a hyperpolarizing effect.
Composed of gap junctions between cells, transmit signals much more quickly than chemical synapses. The signal can propagate bidirectionally.
Consists of a space between two neurons that is crossed by neurotransmitters.
In a given chemical synapse, one cell always releases a neurotransmitter and the other always receives it.
Motor End Plate
The connection between a neuron and a muscle, an example of a chemical synapse.
Chemicals that are released into the synapse by a presynaptic neuron and attach to receptors on the postsynaptic cell.
Second Messenger System
Receptors may be this kind, meaning they activate another molecule inside the cell to make changes.
Support cells in nervous tissue, do not convey electrical signals, are capable of cell division.
Electrically insulating sheaths.
Wrap their entire cell bodies around axons, produce myelin.
Areas of the nervous system that are composed of myelinated axons of neurons.
Areas of the nervous system that are composed of bundles of the cell bodies of neurons.
Nodes of Ranvier
Tiny gaps between myelinated areas, action potential jumps from one ____ to the next as quickly as the disturbance moves through the electrical field between them.
The action potential jumps from one node of Ranview to the next as quickly as the disturbance moves through the electrical field between them.
Sensory (Sensor/Afferent) Neurons
Receive signals from a receptor cell that interacts with the environment. The ____ then transfers this signal to other neurons. Located dorsally (toward the back) on the spinal cord.
Transfer signals from neuron to neuron.
Motor (Effector/Efferent) Neurons
Carry signals to a muscle or gland called the effector. Located ventrally (toward the front/abdomen) of the spinal cord.
A bundle of neuron processes.
A neural pathway that controlls an action reflex.
A quick response to a stimulus that occurs without direction from the CNS.
Negative Feedback Loop
A type of self-regulating system where increased output from the system inhibits future production by the system.
Consists of the neurons and support tissue within the brain and the spinal cord. Integrates nervous signals between sensory and motor functions.
Handles the sensory and motor functions of the nervous system. Is divided into the somatic nervous system and autonomic nervous system.
Somatic Nervous System
Contains sensory and motor functions and primarily functions to respond to the external environment.
Coordinates an involuntary response to environmental stimuli, altering processes within the body to produce the most adaptive physiological state and behavior.
Deals with "fight or flight" responses. Increases heart rate and stroke volume, diverts blood away from digestive/excretory systems to skeletal muscles.
Works to "rest and digest". Slows the heart rate and increases digestive and excretory activity.
The neurotransmitter used by all preganglionic neurons in the ANS and by postganglionic neurons in the parasympathetic branch.
Epinephrine (Adrenaline)/Norephinephrine (Noradrenaline)
Used by the postganglionic neurons of the sympathetic ANS.
Controls the basic involuntary functions necessary for survival. Includes the medulla, pons, and midbrain.
Plays an important role in the regulation of the cardiovascular and respiratory systems. Monitor levels of CO2 in the bloodstream.
Coordinates communication between the motor cortex and the cerebellum, facilitating the transfer of motor commands.
Involved in the coordination and planning of movement. Receives and processes sensory, motor, and vestibular input.
The thalamus and hypothalamus.
The control center, processes almost all sensory information before it reaches higher cortical centers, as well as receives motor commands from these cortical areas on their way to the spinal cord.
Regulates many of the body's basic physiological needs by maintaining homeostasis in multiple systems such as temperature and water balance.
Take the system output into consideration, which enables the system to adjust its performance to meet a desired output response.
The location of many higher-level functions of the nervous system that influence the experiences that make us human: consciousness, memory, cognition, planning, emotion.
The location of higher-level (executive) functions such as planning and impulse inhibition. Contains the motor cortex.
Creates a map of the parts of the body, such that specific sets of neurons control certain body parts.
Contains the somatosensory cortex.
Maps the body's sensation of touch. Part of the somatosensory system.
Involves the detection of physical stimuli, creates a map of the body. The devotion of comparatively large portions of the ____ to particular parts of the body makes these regions particularly sensitive to tactile stimuli.
Site where visual information is processed.
Part of the brain concerned with auditory and olfactory information.
Part of the brain that is concerned with memory and emotion.
Lateralization of Cortical Functions
Take place primarily in one hemisphere or the other.
Receptors that detect internal and external stimuli.
A type of sensory receptor, for touch.
A type of sensory receptor, for temperature change.
A type of sensory receptor, for pain.
A type of sensory receptor, for light.
A type of sensory receptor, for taste, smell, and blood chemistry.
A type of electromagnetic receptor, detect the physical stimulus of photons that enter the eye. Do not generate action potentials.
A stimulus that occurs repeatedly at the same intensity level evokes fewer and fewer action potentials in the sensory receptors.
Where light strikes the eye. Nonvascular, largely made from collagen, clear, refractory index of about 1.4.
Part of the eye, has a spherical shape, but stiff supersensory ligaments tug on it and tends to flatten it. The shape can be adjusted according to the focal length needed to focus on the object.
Circles the lens, connects to the supersensory ligaments. When the ___ contracts, the opening of the circle decreases, allowing the lens to become more like a sphere.
Covers the inside of the back (distal portion) of the eye. Contains rods and cones.
Part of the retina, contain the pigment rhodopsin. Cannot distinguish color.
Part of the retina, three different types. Can distinguish color.
The colored portion of the eye that creates the opening called the pupil. Contains circular and radial muscles.
Opening in the eye, can change size to restrict light or allow more light in.
The axons of the ganglion cells gather to form the ____, which leaves the eye to convey visual information to the brain.
Lateral Geniculate Nucles (LGN)
Part of the thalamus, preserves the visual map created by the ganglion cells and projects this information to the primary visual cortex.
Primary Visual Cortex
Located in the occipital lobe, receives visual input from the LGN.
Travels to the temporal lobe towards the base of the brain and is involved in object recognition ("what").
Projects to the parietal cortex and is involved in perceiving the location of objects ("where").
An instrument that condenses sound into a tiny space, transforms sound from waves of pressure of air into physical vibrations.
Composed of the pinna and external auditory canal.
Contains the tympanic membrane and three small bones: maleus, incus, and stapes - act as a lever system, translating the wave into a physical vibration that is conveyed to the oval window.
Composed of the semicircular canals, cochlea, oval window, round window, and vestibulocochlear nerve.
Part of the inner ear, detects sound.
Organ of Corti
Located on the cochlea's basilar membrane, the alternating increase and decrease in pressure causes vibrations on the _____.
Specialized microvilli on the organ of Corti. The movement of these is transduced into neural signals that are sent to the brain.
Part of the inner ear's vestibular system, primarily responsible for detecting twisting of the head.
Part of the inner ear's vestibular system, detect tilting and linear acceleration.
Part of the inner ear, composed of the semicircular canals and the otolith organs.
Sense that contributes to the awareness of the body's location and movement, to give the individual an overall sensation of the body.
Medial Geniculate Nucleus
Located in the thalamus, represents the thalamic relay between the inferior colliculus and the auditory cortex.
In the temporal lobe, receives information from the thalamus. Where the detection of complex features of auditory information, such as patterns, takes place.
Formed by the axons of the olfactory chemoreceptors.
Chemicals binding to chemoreceptors trigger an action potential that is trasmitted by the olfactory nerve to neurons of the _______.
Unlike in the other sensory systems, neural signals do not pass through the thalamus before reaching high cortical levels in the brain.
Pyriform (Olfactory) Cortex
The olfactory bulb projects directly to the ___ in the temporal lobe. Conveys olfactory information to the orbitofrontal cortex. Also projects to the amygdala and hippocampus.
An odorant that is not perceived consciously, exert a subconscious influence on behaviors related to the amygdala and hypothalamus, particularly aggression and sexual behavior.
Release enzymes to the external environment through ducts. Include sudoriferous, sebaceous, mucuous, and digestive glands.
Release hormones directly into the bloodstream.
Peptide, steroid, tyrosine
Derived from peptides, are water soluble, can move freely through blood but have difficulty diffusing through the cell membrane of the effector.
Target cell: the cell that the hormone is meant to affect.
Derived from and often chemically similar to cholesterol. Are lipids, hydrophobic, typically require a carrier protein in order to dissolve into the bloodstream.
Formed by enzymes in the cytosol or rough ER. Do not all have either water or lipid solubility in common.
Located in the brain beneath the hypothalamus, regulates much of the endocrine system .
Human Growth Hormone (HGH)
A peptide, stimulates growth in almost all cells of the body by increasing episodes of mitosis, increasing cell size, increasing the rate of protein synthesis, mobilizing fat stores, increasing the use of fatty acids for energy, decreasing use of glucose. Also called somatotropin.
Adrenocorticotropic Hormone (ACTH)
A peptide, stimulates the adrenal cortex to release glucocorticoids via the second messenger system using cAMP.
Thyroid-Stimulating Hormone (TSH)
A peptide, stimulates the thyroid to release T3 and T4 via the second messenger system using cAMP. Increases thyroid cell size, number, and the rate of T3 and T4 secretion. Also called thyrotropin.
A peptide, promotes lactation by the breasts.
Composed mainly of support tissue for nerve endings extending from the hypothalamus. Oxytocin and ADG are transported from the hypothalamus to the ___, where they are released into the blood.
Antidiuretic Hormone (ADH)
A small peptide hormone which causes the collecting ducts of the kidney to become permeable to water, reducing the volume of urine and concentrating the urine. Also called vasopressin.
A small peptide hormone that increases uterine contractions during pregnancy and causes milk to be ejected from the breasts.
Located on top of the kidneys, produce a variety of hormones, such as adrenaline.
The outside portion of the adrenal gland. Secretes only steroid hormones: mineral corticoids and glucocorticoids.
Secreted by the adrenal cortex, affect the electrolytic balance in the bloodstream.
Secreted by the adrenal cortex, increase blood glucose concentration and effect fat and protein metabolism.
A steroid, a mineral corticoid that acts in the distal convoluted tubule and the collecting duct to increase Na+ and Cl- reabsorption and K+ and H+ secretion.
A steroid, a glucocorticoid that increases blood glucode my stimulating gluconeogenesis in the liver. Liberates fatty acids from adipose cells.
Basal Metabolic Rate
The resting metabolic rate.
T3 and T4
Lipid soluble tyrosine derivatives that diffuse through the lipid bilayer and act in the nuclei of the cells of their effectors. Secreted by the thyroid.
Large peptide hormone released by the thyroid, slightly decreases blood calcium by decreasing osteoclast activity and number.
Released by the beta-cells of the pancreas when blood levels of proteins or carbohydrates are high.
Released by the alpha-cells of the pancreas. Stimulates glycogenesis and gluconeogenesis in the liver.
Parathyroid Hormone (PTH)
A peptide, increases blood calcium. Increases osteocyte absorption of calcium and phosphate from the bone and stimulates proliferation of osteoplasts.
Hormones that have other endocrine glands as their target. Include TSH, ACTH, LH, and FSH. All peptide hormones released from the anterior pituitary.
Blood Chemistry Hormones
Control the concentrations of sodium and calcium in the bloodstream. Peptide hormones released from the posterior pituitary, pancreas, parathyroid, and thyroid.
The concentration of osmotically active particles in solution, which may be quantitatively expressed in osmoles of solute per liter of solution.
Blood Glucose Regulation
Regulated by insulin and glucagon, produced in the pancreas. HGH, cortisol, and epinephrine will also increase blood glucose.
Control how the body reacts to stress. Increase blood pressure and glucose in the bloodstream. Includes epinephrine and cortisol.
Determinants of Metabolic Rate
Major hormones: T3 and T4, produced by the thyroid.
Reproduction and Development Hormones
Released from anterior pituitary, posterior pituitary, gonads, placenta.
Organs involved in the production of gametes.
Male gonads - involved in the production of gametes.
A set of long, twisted tubes in the testes that are lined by Sertoli cells and spermatogonia.
Follicle Stimulating Hormone (FSH)
Secreted by the gonadotrophs of the anterior pituitary gland, regulates the development, growth, pubertal maturation and reproductive processes of the body
Primary male sex hormone, stimulates the germ cells to differentiate into sperm.
Stimulates Leydig cells to release testosterone.
Male sex hormone.
A sperm stem cell before it undergoes meiosis.
Composed of a head, midpiece, and tail.
Where the spermatozoa go to mature.
The tube that connects the testes to the urethra.
Tube that allows urine to pass out of the body.
The complete mixture of spermatazoa and the fluid that leaves the penis upon ejaculation. (Fluid from the seminal vesicles, prostate, and bulbourethral glands).
Releases a fluid rich in sugars that feed the sperm and clotting properties that make semen sticky.
Secretes a slightly alkaline fluid that makes up about 30% of semen.
Bulbourethral (Cowper's) Glands
Secretes a mucus-like fluid that serves to lubricate the end of the penis.
A glycoprotein layer secreted by the granulosa cells that surround the egg.
Upon stimulation by LH, theca cells secrete adrogen, which is converted to ____ by the granulosa cells in the presence of FSH and secreted into the blood.
A dramatic increase in LH secretion just before ovulation, caused by rising estradiol levels.
The bursting of the follicle and release of the egg into the body cavity.
Transport the egg from the ovary to the uterus.
Develops from the remnants of the follicle, secretes estradiol and progesterone throughout pregnancy, or for 2 weeks if there is no pregnancy.
Secreted by the corpus luteum, maintains the uterine lining.
The corpus luteum degrades into the ___ if no pregnancy occurs.
What the oocyte becomes after the second meitoic division.
Forms when the ovum and sperm fuse.
When the zygote is composed of sixteen or more cells.
A thin-walled hollow structure in early embryonic development that contains a cluster of cells called the inner cell mass from which the embryo arises. Filled with fluid.
When the blastocyst lodges in the uterus, approximately the 7th day after fertilization.
Formed when the outer cells of the blastocyst implant in the uterine wall and fuse with the uterine tissue.
Human Chorionic Gonadotropin (HCG)
Prevents the degeneration of the corpus luteum and maintains its secretion of estrogen and progesterone. The first outward sign of pregnancy.
Cells can also communicate directly with one another — and change their own internal workings in response — by way of a variety of chemical and mechanical signals. Allows for specialization of cells.
When a cell becomes committed to a specialized developmental path.
The specialization that occurs at the end of development, forming a specialized tissue cell.
The single-layered blastula is reorganized into this trilaminar ("three-layered") structure. Ectoderm, mesoderm, endoderm.
The process during which the gastrula is formed. Usually 3rd after fertilization.
A primary germ layer. Becomes the epidermis of skin, nervous system, and sense organs.
A primary germ layer. Becomes the skeleton, muscles, blood vessels, heart, blood, gonads, kidneys, dermis of skin.
A primary germ layer. Becomes the lining of the digestive and respiratory tracts, liver, pancreas, thymus, and thyroid.
The embryonic stage after the gastrula. Stage in which part of the ectoderm is differentiated into neural tissue and in which the neural tube, which develops into the brain and spinal cord, is formed.
The process in which the gastrula develops into the neurula.
Occurs when one cell type affects the direction of differentiation of another cell type.
A rodlike cord of cells that forms the chief axial supporting structure of the body of embryos.
The cells of the ectoderm that are close to the neural tube.
Regulated process of cell movement that ensures that cells end up in the correct locations of the structures to which they contribute.
The process by which cells stop proliferating in response to environmental stressors and are ultimately cleared away by immune cells.
Development that occurs before birth.
The biological changes that ultimately lead to sexual maturity.
Small particles suspended in air.
The regulation of body temperature such that it stays within a narrow range.
Increases respiration rate.
An exothermic process, has a cooling effect on the body.
Located at the front of the nose's cavity, trap large dust particles.
Secreted by goblet cells, traps smaller dust particles that were able to bypass the coarse nasal hair.
Move mucus and dust back toward the pharynx to be removed by spitting or swallowing.
Windpipe, lies in the front of the esophagus. Composed of ringed cartilage covered by ciliated mucus cells.
A passage of airway in the respiratory tract that conducts air into the lungs. Branches into bronchioles.
Branches of the bronchi that terminate in grape-like clusters called alveolar sacs.
The terminal ends of the respiratory tree, which outcrop from either alveolar sacs or alveolar ducts. Oxygen diffuses from each of these into an adjacent capillary.
Enables expansion of the chest cavity so that the lungs can expand and breathe in oxygen. It also encloses the thoracic cavity and helps protect the heart and lungs from damage.
Part of the midbrain, signals the diaphragm to contract.
A thin sheet of skeletal muscle that is innervated by the phrenic nerve. Dome-shaped in a relaxed state, flattens upon contraction, expanding the chest cavity.
Resiliency, allows the lungs to force air out of the body.
Alveolar Gas Exchange
Occurs passively, through diffusion.
C = P * solubility
Found inside erythrocytes, binds rapidly and reversibly with oxygen. Composed of four polypeptide subunits, each with a single heme subfactor.
Forms when hemoglobin binds with oxygen.
The interaction process by which binding of a ligand to one site on a macromolecule influences binding at a second site.
How readily hemoglobin acquires and releases oxygen.
Rightward Shift of Oxygen Dissociation Curve
Occurs in response to an increase in carbon dioxide pressure, hydrogen ion concentration, or temperature.
Catalyzes the formation of the bicarbonate ion in the reversible reaction: CO2 + H2O <--> HCO3- + H+
Located in the medulla, affects the control of breathing rate by the medulla.
Located in the carotid arteries and aorta, affects the control of breathing rate by the medulla.
A small increase in the partial pressure of CO2 quickly triggers an increased respiration rate to allow more CO2 to be expired.
The respiratory system adjusts breathing rate, and thus the partial pressure of CO2 in the body, in response to potentially dangerous disturbances to the pH of the bloodstream.
Group of tissues in the body that maintains the form of the body and its organs and provides cohesion and internal support.
Contains the matrix of the blood, which includes water, ions, urea, ammonia, proteins, etc.
Transport fatty acids and steroids, help regulate osmotic pressure of the blood.
Plasma from which the clotting protein fibrinogen has been removed.
Red blood cells, essentially bags of hemoglobin. Do not have organelles, do not undergo mitosis.
Percentage by volume of red blood cells. Typically 35-50%.
White blood cells, do contain organelles, protect the body from foreign substances.
Small portions of membrane-bound cytoplasm torn from megokaryocytes. Capable of making prostaglandins.
Functions to minimize blood loss and facilitate healing when blood vessels are damaged.
The final product of the blood coagulation step in hemostasis.
A plasma protein that forms fibrin threads that attach to platelets to form a tight plug.
Closed Circulatory System
The cardiovascular system is this type of system because it contains no openings for the blood to leave the vessels.
The first half of the circulation, directs oxygenated blood to the tissues and then returns deoxygenated blood to the heart.
The left lower chamber of the heart that receives blood from the left atrium and pumps it out under high pressure through the aorta to the body.
The largest artery in the body, arises from the left ventricle of the heart.
The aorta branches into these.
Arteries branch into these.
Arterioles branch into these.
Collect deoxygenated blood from capillaries.
Collect blood from venules.
Superior Vena Cavae
A large vein that receives blood from the head, neck, upper extremities, and thorax and delivers it to the right atrium of the heart.
Inferior Vena Cavae
A large vein that receives blood from the lower extremities, pelvis and abdomen and delivers it to the right atrium of the heart.
The right upper chamber of the heart. Receives deoxygenated blood from the body through the vena cava and pumps it into the right ventricle.
Second half of circulatory system, transports blood to the lungs for oxygenation.
The lower right chamber of the heart that receives deoxygenated blood from the right atrium and pumps it under low pressure into the lungs via the pulmonary artery.
Receives blood from the right ventricle and passes it to the arterioles and then capillaries of the lungs.
Collect blood from the capillaries, veins, and venules of the lungs, leading to the heart.
The upper right chamber of the heart. Receives oxygenated blood from the lungs and pumps it down into the left ventricle which delivers it to the body.
Sinoatrial (SA) Node
A group of specialized cardiac muscle cells located in the right atrium, sets the pace for the heart to contract.
A parasympathetic nerve, innervates the SA node, slowing the contractions to produce the typical resting heart rate.
Atrioventricular (AV) Node
Located in the interatrial septum, creates a delay which allows the atria to finish their contraction and squeeze their contents into the ventricles before the ventricles contract.
Bundle of His
Conductive fibers in the wall separating the ventricles. The action potential moves from the AV node to the ____.
Conductive fibers in the ventricular walls, part of the impulse-conducting network of the heart, that rapidly transmit impulses from the atrioventricular node to the ventricles
The thin layer of cells that line the interior surface of all blood vessels. Only one cell thick in capillaries.
The highest pressure, measured in the arteries during systole.
The lowest pressure, occurs during relaxation of the ventricles and filling of the atria.
Total Peripheral Resistance
The overall resistance of the entire systemic circulatory system.
Regulation of Plasma Volume
The renin-angiotensin-aldosterone system regulates blood pressure through the _______.
An ester formed between one or more fatty acids and glycerol.
The lymphatic system is this type of system because fluid enters at one end and leaves at the other.
Quick and non-specific, providing a generalized protection from most intruding organisms and toxins.
Acquired (Adaptive) Immunity
Develops more slowly and only after the body has experienced the initial attack, provides protection against specific organisms or toxins.
Functions to "wall-off" affected tissue and local lymph vessels from the rest of the body, impeding the spread of infection.
Cells that ingest dangerous substances and then destroy them.
The first to attack infectious agents that pass through the skin or other barrier defenses and enter the body.
Humoral or antibody-mediated immunity.
Differentiate and mature in the adult bone marrow and the fetal liver, promote antibody-mediated immunity.
Immunoglobin, can recognize and bind to a particular potentially harmful foreign particle.
A potentially harmful foreign particle.
The process by which an antibody (or BCR) recognizes a foreign particle.
The immune response that results from the first exposure to an antigen, requires 20 days to reach its full potential.
Synthesize free antibodies and release them into the blood, can survive for decades or a lifetime.
Secondary immune-system components that have an affinity for a particular antigen. Originate from lymphocytes that develop and are activated in the bone marrow.
In the case of re-infection, memory B-cells and plasma cells can be called upon to synthesize antibodies. Requires about 5 days to reach its full potential.
Mature in the thymus, has an antibody-like protein at its surface that recognizes antigens. Never make free antibodies.
Major Histocompatibility Complex (MHC)
Group of genes that code for proteins found on the surfaces of cells that help the immune system recognize foreign substances.
MHC Class I
Display antigens derived from intracellular pathogens such as viruses and some bacteria.
MHC Class II
Display antigens derived from extracellular pathogens. Displayed by phagocytic cells.
A hyperactive immune system attacks the body's own tissues.
Only certain types of cells are permitted to mature and proliferate.
Cells that are not capable of recognizing antigens in the context of host MHC molecules undergo apoptosis.
Cells that respond too strongly to MHC molecules with self-antigens undergo apoptosis.
Main Components of Digestive Tract
Mouth, esophagus, stomach, small intestine, large intestine, anus.
The process of taking in food through the mouth.
Enzyme in saliva, initiates the chemical breakdown of food.
A contraction of the smooth muscle in the digestive tract, creates a wave that pushes along partially digested food.
Major Regions of Stomach
Fundus, body, pylorus.
A ring of muscle that is normally contracted so that there is no opening at its center.
A combination of acid, enzymes, and hormones released by the cells in the lining of the stomach. Maintains the acidic environment in the stomach.
Stomach Exocrine Glands
In recesses called gastric pits, use ducts to deliver their secretions to specific locations in the external environment.
Mucous Cells (Stomach)
Secrete mucus, line the stomach wall and the necks of the exocrine glands. Lubricates the stomach wall.
Chief (Peptic) Cells
Found deep in the exocrine glands, secrete pepsinogen.
Parietal (Oxyntic) Cells
Found in the exocrine glands of the stomach. Secrete HCl into the lumen of the stomach through active transport.
Secrete gastrin, communicate with the outside and inside of the body.
The zymogen precursor to pepsin.
Begins protein digestion.
A large peptide hormone that stimulates parietal cells to secrete HCl.
The first part of the small intestine, where most digestion occurs.
The second part of the small intestine, where absorption occurs.
The last part of the small intestine, where absorption occurs.
Finger-like projections in the small intestine. Increase the surface area of the internal wall, allowing for greater digestion and absorption.
A capillary network and a lymph vessel, inside each villus.
On the apical side of each villus are much smaller finger-like projections, further increase surface area.
A fuzzy covering composed of the microvilli, contains membrane bound digestive enzymes.
Epithelial cells that secrete mucus to lubricate the intestine and help protect the brush border from mechanical and chemical damage.
Aids the digestive process, acts as an edocrine glad that secretes insulin and glucagon, acts as an exocrine gland, secretes bicarbonate ions to neutralize acid from the stomach.
Secreted by the pancreas to neutralize acid from the stomach.
Degrades proteins into small polypeptides.
Degrades proteins into small polypeptides.
Hydrolyzes polysaccharides to disaccharides and trisaccharides, degrades nearly all of the carbohydrates from the chyme into oligosaccharides.
Enzyme that degrades fat, specifically triglycerides.
An ester derived from glycerol and three fatty acids.
Produced in the liver and stored in the gall bladder, aids the digestion of lipids in the small intestine.
Stores bile and releases bile through the cystic duct.
Parts of the Large Intestine
Ascending colon, transverse colon, descending colon, sigmoid colon, rectum.
Functions of Large Intestine
Water absorption and electrolyte absorption.
Composed of 75% water, the remaining mass is 30% bacteria, 10-20% fat, 10-20% organic matter, 2-3% protein, and 30% roughage and undigested matter.
Enteric Nervous System
Consists of a large network of neurons surrounding the digestive organs, helping to regulate processes such as smooth muscle contraction, fluid exchange, blood flow to digestive organs, and hormone release.
The formation of glycogen.
The breakdown of glycogen.
The liver converts ammonia to ___, which is excreted in the urine.
Metabolic Functions of the Liver
Carbohydrate metabolism, fat metabolism, protein metabolism, detoxification.
Carbohydrate Metabolism (Liver)
The liver maintains normal blood glucose levels through gluconeogenesis, glycogenesis, and release of glucose stores according to the needs of the body.
Fat Metabolism (Liver)
The liver synthesizes bile from cholesterol and converts carbohydrates and proteins into fat. When the liver mobilizes fats or proteins for energy, the acidity of the blood increases.
Protein Metabolism (Liver)
The liver deaminates amino acids, forms urea from ammonia in the blood, synthesizes plasma proteins, and synthesizes nonessential amino acids.
Detoxified chemicals are secreted by the liver as part of bile or modified so that they can be excreted by the kidney.
Blood Storage (Liver)
The liver can expand to act as a blood reservoir for the body.
Glycogen Storage (Liver)
The liver stores large amounts of glycogen as an energy reserve that can be used to regulate blood glucose levels.
Vitamin Storage (Liver)
The liver stores vitamins such as vitamin A, D, and B12. It also stores iron.
Kupffer cells phagocytize bacteria picked up from the intestines.
Kupffer cells also destroy irregular erythrocytes although most irregular erythrocytes are destroyed by the spleen.
Maintains homeostasis of the body fluid volume and thus regulates blood pressure, maintains homeostasis of plasma solute composition and helping control plasma pH, excreting waste products such as urea, uric acid, ammonia, and phosphate.
The functional unit of the kidney.
Blood entering a nephron first flows into a capillary bed called the ___.
Together with the glomerulus, it makes up the renal corpuscle.It serves as a filter to remove organic wastes, excess inorganic salts, and water
The pressure exerted by gravity at a given point within a fluid that is at equilibrium, increasing in proportion to depth from the surface.
Screen out blood cells and large proteins, preventing them from entering Bowman's capsule.
Where secretion and most reabsorption takes place in the kidney.
Loop of Henle
Dips into the medulla, functions to increase the solute concentration, and thus the osmotic pressure, of the medulla.
Counter-Current Multiplier Mechanism
Applies the single effect, which creates a static gradient, to a dynamic system where fluid is continually moving through the loop of Henle.
Reabsorbs Na+ and Ca2+ while secreting K+, H+, and HCO3-.
Carries the filtrate into the highly osmotic medulla. Impermeable to water but is sensitive to ADH, in which it becomes permeable to water.
Monitors filtrate pressure in the distal tubule. Specialized cells secrete the enzyme renin when filtrate pressure is too low.
Functions of Muscle
Body movement, stabilization of body position, movement of substances through the body, generating heat to maintain body temperature.
A type of striated muscle, the tissue that is commonly called "muscle" in everyday language. Is voluntary muscle.
Can be consciously controlled to produce specific desired movements, is innervated by the somatic nervous system.
Connective tissue that attaches muscle to bone.
Connective tissue that attaches bone to bone.
Peripheral Circulatory Assistance
Contraction of skeletal muscles helps squeeze blood and lymph through their respective vessels, aiding circulation.
The rapid contraction, or shaking, of skeletal muscle to warm the body.
The smallest functional unit of the contractile apparatus in skeletal muscle. Composed of many strands of thick filaments and thin filaments.
Made of myosin.
Play a role in muscle contraction, make up thick filaments.
Made up of actin.
Play a role in muscle contraction, make up thin filaments.
Attaches to actin, aids in muscle contraction.
Attaches to actin, aids in muscle contraction.
Separates one sarcomere from the next and is where actin filaments attach.
The area pf the sarcomere containing actin only (includes the Z line).
The area of the sarcomere containing myosin only.
The area of the sarcomere where myosin is present, including where it overlaps with actin (includes the H zone).
The midline of the myosin fibers in the sarcomere.
The specialized endoplasmic reticulum of the muscle cell, surrounds each myofibril.
Attaches to a muscle cell at a motor end plate, forming a neuromuscular junction.
Facilitate the uniform contraction of the muscle by allowing the action potential to spread through the muscle cell more rapidly.
Sliding Filament Model
Myosin and actin work together by sliding alongside each other to create the contractile force of skeletal muscle.
Forms btween the thick and thin filaments when myosin heads bind to the actin.
May occur after sustained use of the same motor unit, the nerve supplying the unit can become temporarily unable to supply the signals necessary to continue frequent, high intensity contraction of the muscle.
The need for increased oxygen after exercise in order to metabolize the excess lactic acid produced.
Type I (Fiber)
Slow twitch fibers
Type II (Fiber)
Fast twitch fibers
Speed of contraction
A specialized, electrically-excitable tissue, which permits the propagation of the electrical signals that cause the heart to beat normally.
Receives nervous input from the autonomic nervous system.
Increases heart rate in the cardiac muscle.
Via the vagus nerve, decreases heart rate.
Composes the muscular layer of internal organs and blood vessels. Contain thick and thin filaments but are not organized into sarcomeres. Contain intermediate filaments.
Connective tissue, supports and protects various organs of the body.
Functions of Bone
Support of soft tissue, protection of internal organs, assistance in body movement, mineral storage, blood cell production, and energy storage in the form of adipose cells in bone marrow.
Composed of inorganic minerals and proteins, surrounds bone tissue.
Secrete collagen and inorganic compounds upon which bone is formed. Incapable of mitosis.
Exchange nutrients and waste minerals with the blood. Incapable of mitosis.
Reabsorb bone matrix, releasing minerals back into the blood. Thought to develop from the white blood cells called monocytes.
Trabecular or cancellous bone, contains red bone marrow.
Red Bone Marrow
The site of red blood cell development.
Surrounds a hollow area inside the diaphysis known as the medullary cavity, which holds yellow bone marrow.
Specialized Bone Types
Long, short, flat, irregular.
Have a shaft that is curved for strength. Composed of compact and spongy bone. Leg, arm, finger, toe bones.
Roughly cuboidal in shape, include the ankle and wrist bones.
Provide organ protection and large areas for muscle attachment. Include skull, sternum, ribs, and shoulder blades.
Have an irregular shape and variable amounts of compact and spongy bone. Ossicles of the ear.
Flexible, resilient connective tissue. Composed primarily of collagen and has great tensile strength.
Locations where bones connect in ways that allow for varying amounts of movement, depending on type.
Occur between two bones held closely and tightly together by fibrous connective tissue, permitting extremely minimal movement. Connection between teeth and mandible.
Occur between two bones tightly connected by cartilage, allow little movement. Ribs and sternum, pubic symphysis in the pelvis.
Bones bound by these joints are not bound directly by the intervening cartilage, so a wide range of movement is possible. Separated by a capsule filled with synovial fluid.
The largest organ in the body and has a wide variety of functions.
Functions of the Skin
Thermoregulation, protection, environmental sensory input, osmoregulation, immunity, blood reservoir, vitamin D synthesis.
The skin helps to regulate body temperature. Blood conducts heat from the core of the body to the skin, dissipated by evaporation and radiation.
Allows skin to regulate body temperature.
The skin is a physical barrier to abrasion, disease organisms, many chemicals, and UV radiation.
Environmental Sensory Input (Skin)
The skin gathers information from the environment by sensing temperature, pressure, pain, and touch.
Skin is relatively impermeable to water, protecting against dehydration. Excretion and sweating are ways that skin contributes to ____.
Besides being a physical barrier to bacteria, specialized cells of the epidermis are components of the immune system.
Blood Reservoir (Skin)
Vessels in the dermis hold up to 10% of the blood in a resting adult.
Vitamin D Synthesis (Skin)
UV radiation activates a molecule in the skin that is a precursor to vitamin D. The activated molecule is modified by enzymes in the liver and kidneys to produce vitamin D.
The superficial part of the skin, is avascular epithelial tisssure, consist of four major cell types: keratinocytes, melanocytes, Langerhans cells, Merkel cells.
The deeper part of the skin, connective tissue derived from mesodermal cells. Hair follicles are embedded here.
Superficial fascia or hypodermis. This subcutaneous layer is an important heat insulator for the body.
Cells in the epidermis that produce the protein keratin, which helps waterproof the skin.
Cells in the epidermis that transfer melanin to keratinocytes.
Cells in the epidermis that interact with the helper T-cells of the immune system.
Cells in the epidermis that attach to sensory neurons and function in the sensation of touch.
Layers of the Epidermis
Four layers, five in the palms and soles of the feet.
A protective structure that forms when exposure to friction or pressure stimulates the epidermis to thicken.
A column of keratinized cells held tightly together. Grows as new cells are added to the base.
Keratinized cells on your hands and feet.
Two types: eccerine (found over entire surface of skin, respond to heat) and apocrine (congregated in certain regions of the dermis, respond to stress). Are found in the skin separate from hair follicles.
THIS SET IS OFTEN IN FOLDERS WITH...
MCAT 2015: Psychology & Sociology
MCAT 2015 Essential Amino Acids
TPR MCAT 2015: Lab Techniques
TPR MCAT 2015: Summary of Reactions
YOU MIGHT ALSO LIKE...
MEDA 111 Quiz 4
MEDA 111 Quiz 4
OTHER SETS BY THIS CREATOR