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A&P Exam 1 (Chapters 1, 2, 3)

Terms in this set (333)

the cell is... (w/ two dashes)
the basic unit of life
-cells are the smallest unit that can carry out the functions of life
-all organisms are composed of cells
Chemicals are...
substances with unique molecular composition that are used in or produced by chemical reactions
What is metabolism?
-the ability to extract energy from fuel put into the body and generate waste products
-metabolic processes either build up or breakdown substances depending on the needs of the organisms
Growth is...
where building outweighs breakdown processes
Growth leads to...
an increase of individual cells or an increase of number of cells
Excretion is...
a process that an organism uses to eliminate potentially harmful waste products created by metabolic processes
Responsiveness/irritability is...
the ability of an organism to sense and react to changes or stimuli in their environment
Movement includes...
-the ability of an entire organism to move
-or movement of individual cells
-or of materials within or between cells of an organism
Reproduction's two forms in multicellular organisms are...
-individual cells reproduce within organisms during growth and to replace damaged or old cells
-organism itself reproduces to yield similar offspring
Describe the chemical level of organization...
the smallest level, the foundation for each successive level, ranges from tiny atoms to complex chemicals structures called molecules; composed of between two and thousands of atoms
Describe the cellular level of organization...
formed by groups of many different types of molecules combined in specific ways to form cellular structures
At the tissue level...
two or more cell types cooperate to perform a common function
Tissues consist of two components...
cells and the surrounding extracellular matrix
Tissues vary from...
membrane sheets that cover body cavities to irregularly shaped cartilage found in the nose
Describe the organ level...
consists of two or more tissue types combined to form a structure or organ; has recognizable shape and performs a specialized task
Describe the organ system...
the body's organs are grouped into organ systems, which consists of two or more organs that together carry out a broad function in the body
How many organ systems does the body have?
11
What two levels work together to ensure the survival of the organism as a whole?
Organs and organ systems
Systemic anatomy is...
the approach used in the textbook; examines the human body primarily by looking at individual organ systems
Regional anatomy...
divides the body into regions of study such as the head and neck
Surface anatomy...
studies surface markings of the body
Gross anatomy...
examines structures that can be seen with unaided eye
Microscopic anatomy...
studies structures that can only be seen with the aid of a microscope
Histology is...
the study of tissues
Cytology is...
the study of cells
Anatomical position is...
a common frame of reference from which all body parts and regions are described
-a position where the body is facing forward with feet slightly apart, arms at the side and palms facing forward and open
-body is always referred to as if it were in anatomical position
How are right and left referred to on the body
As the right and left sides of the body, not our own
Directional terms are..
another means of ensuring accurate communication; describes the relative location of body parts and markings
The front of humans is referred to as...
anterior (ventral)
The back of humans is referred to as...
posterior (dorsal)
The head of humans is referred to as...
superior (cranial)
The tail of humans is referred to as...
inferior (caudal)
Proximal refers to something being...
closer to the point if origin
Distal refers to being...
farther from the point of origin
What is the imaginary line that runs down the middle of the body
the midline
What refers to a position closer to the midline?
medial
What refers to a position further from the midline?
Lateral
What refers to a position closer to the surface of the body?
Superficial
What refers to a position further from the surface of the body?
Deep
What are the two regions of the body and what do they include?
The axial region
-the head, neck, and trunk
The appendicular region
-the upper and lower limbs or appendages
The three primary planes of section provide a means of...
studying the form and function of a body region by dividing up the body part for examination
The sagittal plane...
divides the body into right and left sections
The midsagittal plane...
divides the body or body part into equal right and left sections
The parasagittal plane...
divides the body or body part into unequal right and left sections
The frontal plane (coronal plane)...
divides the body or body part into anterior and posterior sections
The transverse plane (horizontal plane)....
divides the body or body part into superior and inferior sections, or proximal and distal sections
The oblique plane...
taken at an angle and is useful for examining structures that are difficult to examine using only the three primary planes of section
A cavity is...
any fluid-filled space . within the body
What are the two main cavities and what is their general function?
Dorsal and ventral cavities
-protect internal organs and allow them to move and expand as necessary to perform their functions
The dorsal body cavity is...
largely located on the posterior side of the body, has two cavities that are continuous and filled with cerebrospinal fluid (CSF) which . bathes and protects both the brain and spinal cord
The cranial cavity is...
located within the skull, protects the brain
The vertebral (spinal) cavity is...
located with the vertebral column, protects the spinal cord
The ventral body cavity is...
separated into two divisions by the diaphragm
-the thoracic cavity is superior
-the abdominopelvic cavity is inferior
The thoracic cavity is divided into the following three smaller cavities...
-the pleural cavity
-the mediastinum
-the pericardial cavity
The pleural cavity...
surround either the left or right lung
The mediastinum is...
found between the pleural cavities, and houses the heart, great vessels, trachea, and esophagus
-it is not located within a serous membrane
The pericardial cavity is...
found within the mediastinum, and is within a serous membrane that surrounds the heart
The abdominopelvic cavity is...
subdivided into the superior abdominal cavity and the pelvis cavity
The abdominopelvic cavity...
contains organs from several systems including the digestive, lymphatic, reproductive, and urinary
-spans from the diaphragm to the bony pelvis
The peritoneal cavity is...
an abdominal subcavity found within a serous membrane
What are the quadrants of the abdominopelvic cavity?
Right upper quadrant
Right lower quadrant
Left upper quadrant
Left lower quadrant
What are the regions of the abdominopelvic cavity?
Serous membranes are...
formed by thin sheets of tissue that fold over themselves to create a continuous double-layer structure with space between their layers
What is serous fluid?
watery slippery lubricant that fills the space between membrane layers, produced by the cells of the membrane
What is the function of serous fluid?
It prevents friction caused by the movement of organs
The visceral layer is....
a part of the serous membrane that is in contact with the underlying organ
The parietal layer is...
a outermost part of the serous membrane
What are the three serous body . cavities?
Pleura, pericardium, and peritoneum
The pleura membranes consist of...
-the outer parietal pleura that follow the contours of the thoracic wall
-and the inner visceral pleura that run along the surface of the lungs
-the thin space enclosed by the pleura membranes forms the pleural cavities
The pericardium membranes consist of...
-the outer parietal pericardium that separates the heart from the mediastinum
-and then inner visceral pericardium that lies directly on the heart muscle
-the space created by the pericardial membranes forms the pericardial cavity
The peritoneum membranes consist of...
-the outer parietal peritoneum
-and the inner visceral peritoneum
-the space between these layers forms the peritoneal cavity
-surrounding some of the abdominal organs
The peritoneal cavity is an extensive cavity but it doesn't cover every organ like the...
kidneys, they lie outside of and behind the parietal peritoneum and are thus called retroperitoneal organs
What are the four core principles?
feedback loops, structure/function relationship, gradients, and cell-to-cell communication
Homeostasis is...
the maintenance of the body's stable internal environment through self-regulation
Homeostatic imbalances are...
disturbances in homeostasis that can lead to disease or death if left uncorrected
The body's internal environment is...
the result of a wide range of coordinated processes or variables including temperature, chemical composition of blood and other body fluids, and many others
Feedback loops are...
A circular mechanism whereby feedback is reintroduced into the system, in a looping chain of events that influence on another
Negative feedback loops are...
mechanisms that oppose the initial change in a regulated variable and reduce the output
Generally what are the steps involved in a typical negative feedback loop?
-there is a change in homeostasis
-this triggers a stimulus to alert the body
-this stimulus alerts a receptor
-the receptor signals the control center which determines what was changed
-The control center then sends chemical messengers or signals to effectors
-The effectors can change conditions and trigger body responses
-the body will return to homeostasis
Positive feedback is...
less common, the effector activity increases and reinforces the initial stimulus and shuts off when conditions return to the normal range, like a fever
The structure/function relationship states...
that form follows function
A gradient is...
present any time more of something exists in one area than another where the two areas are connected
What are the three common gradients found in the body?
-when there is a difference between two connected regions
-the temperature gradient
-the concentration gradient
-the pressure gradient
Communication is usually...
accomplished with either chemical messengers or electrical signals, in which one cell triggers a response from another cell
The difference between electrical signals and chemical messengers is...
that electrical signals are usually transmitted between neighboring cells while chemical messengers can affect neighboring cells or travel to distant cells before they cause an effect
Matter is...
anything that has mass and occupies space
The three states in which matter can exist are...
solid, liquid, gas
Chemistry is...
the study of matter and its interactions
An atom is...
the smallest unit of matter that retains its original properties
Subatomic particles are....
protons, neutrons, electrons
Protons and neutrons are found in...
the central core of the atom know as the atomic nucleus
-electrons are outside
Protons have...
a positive charge
Neutrons have...
a neutral/no charge
What is bigger a proton or a neutron?
A neutron
Electrons have...
a negative charge
All atoms are electrically neutral, meaning...
they have no charge; the number of protons and electrons are equal, cancelling out each other
The electron shell is...
the region surrounding the atomic nucleus where the likelihood or probability that an electron may exist
-can only hold a certain number of electrons
-first shell: 2
-second shell: 8
-third shell: 10, but is satisfied with 8
-can have more than 3
The atomic number is...
the number of protons in the nucleus
An element is...
a substance that cannot be broken down into a simpler substance by chemical means
-each element is made of atoms with the same number of protons
What are the four major elements that make up the human body?
hydrogen, oxygen, carbon, and nitrogen
-along with 7 mineral elements and 13 trace elements
The mass number is...
equal to the sum of all of the protons and neutrons in the atomic nucleus
An isotope is...
an atom with the same atomic number and the same number of protons, but different mass number and different number of neutrons
Radioisotopes are...
unstable isotopes with high energy or radiation that can be released by radioactive decay; this allows them to assume a more stable form
Matter can be combined physically to form a...
mixture
A mixture is...
when atoms of two or more elements physically intermix without changing chemical nature of the atoms themselves
Suspension is a mixture containing...
two or more components with large, unevenly distributed particles; will settle out when left undisturbed
Colloids are mixtures containing...
two or more components with small, evenly distributed particles; will not settle out
Solutions are mixtures containing...
two or more components with extremely small, evenly distributed particles; will not settle out; contain a solute dissolved in a solvent
A molecule is...
when the atoms of two or more of the SAME element are combined by forming chemical bonds
A chemical bond is...
not a physical structure but rather an energy relationship or an attractive force between atoms
A compound is...
when the atoms of two or more DIFFERENT elements are combined by forming chemical bonds
Macromolecules are...
very large molecules composed of many atoms
Molecular formulas are...
a way to represent molecules symbolically with letters and . numbers
Chemical bonds are formed when...
valence electrons in the valence shell of atoms (the outermost shell) interact
Valence electrons determine...
how an atom interacts with other atoms and whether it will form bonds with a specific atom
The octet rule states...
an atom is most stable when it has 8 electrons in its valence shell
The duet rule states...
atoms with 5 or fewer electrons are most stable when the electron shell holds 2 electrons
An ionic bond is...
formed when electrons are transferred from a metal atom to a nonmetal atom and results in the formation of ions
A salt is...
the ionic compound formed when the attraction between opposite charges from an anion and cation hold/bond the atoms to one another
A cation is...
a positively charged ion
An anion is...
a negatively charged ion
Covalent bonds are...
the strongest bond, formed when two or more nonmetals share electrons between themselves
Electronegativity is...
a property stating that all elements have protons that can attract electrons
Electronegativity increases from...
the bottom left to the upper right, making fluorine (F) the most electronegative element
The more electronegative an element is...
the more strongly it attracts electrons, pulling them away from less electronegative elements
Nonpolar covalent bonds result...
from two nonmetals in a molecule with similar or identical electronegativities pull with the same force and share the electrons equally
What three situations do nonpolar molecules occur in?
-atoms sharing electrons are the same element
-arrangement of atoms makes one atom unable to pull more strongly than another atom
-the bond is between carbon and hydrogen
Polar covalent bonds form...
polar molecules when nonmetals with different electronegativities interact, resulting in an unequal sharing of electrons
The atom with the higher electronegativity becomes....
partially negative as it pulls and holds the shared electrons close to itself
The atom with the lower electronegativity becomes...
partially positive as it allows the shared electrons to be pulled away toward the other atom
Hydrogen bonds are...
weak attractions between the partially positive end of one dipole and the partially negative end of another dipole
-responsible for surface tension in water
-where air and water meet the polar is stronger than the nonpolar attractions
Chemical notation is...
a series of symbols and abbreviations that is used to demonstrate what occurs in a reaction
The two parts of a chemical equation are
the reactants and products
The reactants are...
on the left side of the equation, the starting ingredients, will undergo the reaction
The products are...
on the right side of the equation, are results of the chemical reaction
When does a chemical reaction occur?
every time a chemical bond is formed, broken, or rearranged, or when electrons are transferred between two or more atoms
Energy is...
the capacity to do work or put matter into motion or fuel chemical reactions
Potential energy is...
stored, but can be released to do work at some later time
Kinetic energy is...
potential energy that has been released or set in motion to perform work
All atoms have what type of energy?
Kinetic energy because they are in constant motion and the faster they move the greater that energy
What are the three forms of energy found in the body?
chemical, electrical, and mechanical
-each of which can be potential or kinetic depending on the location or process
Chemical energy is...
found in bonds between atoms, drives nearly all chemical processes
Electrical energy is...
generated by movement of charged particles or ions
Mechanical energy is...
energy directly transferred from one object to another
Endergonic reactions are...
reactions that require input of energy from another source; products contain more energy than reactants because energy was invested so reaction could proceed
Exergonic reactions are...
reactions that release excess energy so products have less energy than reactants
Catabolic reactions occur...
(decomposition reactions)
when large substances are broken down into smaller substances; usually exergonic
Exchange reactions occur...
when one or more atoms from reactants are exchanged for one another
Oxidation-reduction reactions (redox reactions) are...
a special kind of exchange reaction that occur when electrons and energy are exchanged instead of atoms; usually exergonic
Oxidized=loses electrons
Reduced=gain electrons
Anabolic reactions occur...
(synthesis reactions)
when small simple subunits are united by chemical bonds to make large more complex substances; usually endergonic
Activation energy is...
the energy atoms must collide with to overcome the repulsion of an their electrons
What factors increase the reaction rate by either reducing the activation energy or increasing the likelihood of strong collisions between reactants?
Concentration, temperature, reactant properties, and the presence or absence of a catalyst
Concentration influences reaction rate because...
when reactant concentration increases, more reactant particles are present, increasing the chance of successful collisions between reactants
Temperature influences reaction rate because...
raising the temperature of the reactants increased kinetic energy of their atoms leading to more forceful and effective collisions between reactants
Particle size and phase influence reaction rate because...
-smaller particles move faster with more energy than larger particles
-reactant particles in the gas phase have a higher kinetic energy than those in either solid or liquid phase
Catalysts are...
substances that increase reaction rate by lowering activation energy without being consumed or altered in the reaction
The main properties of enzymes are...
-they speed up reactions by lowering the activation energy
-they are highly specific for individual substrates (substances that can bind to the enzymes active site)
-they do not alter the reactants or products
-they are not permanently altered in reactions catalyzed
The induced-fit mechanism...
describes enzyme's interaction with its substrates; binding of substrate causes a small shape change that reduces the energy of activation
Biochemistry is...
the chemistry of life (grouped into inorganic and organic compounds)
Inorganic compounds...
generally do not contain carbon bonded to hydrogen, and include water, acids, bases, and salts
Organic compounds...
are defined as those that do contain carbon bonded to hydrogen
Water makes up how much of the mass of the human body?
60-80%
What are the four main properties of water?
-it has a high heat capacity so it is able to absorb heat without significantly changing temperature itself
-it carries heat with it when it evaporates
-it cushions and protects body structures because of relatively high density
-it acts as a lubricant between two adjacent surfaces (reduces friction)
What serves as the body's primary solvent and is often called the universal solvent because so many solutes will dissolve in it entirely, or to some degree?
Water
Water is only able to dissolve solutes that are...
hydrophilic or those with fully or partially charged ends: "like dissolves like"; water generally dissolves ionic and polar covalent solutes
Solutes that do not have full or partially charged ends are known as...
hydrophobic and do not dissolve in water, this group includes uncharged nonpolar covalent molecules such as oils and fats
The study of acids and bases can be based off of...
hydrogen ions
An acid is...
a hydrogen ion or proton donor, number of hydrogen ions increases in water when acid is added
A base is...
a hydrogen ion acceptor, number of hydrogen ions decreases in water when a base is added, high in hydroxide ions
The pH scale...
ranges from 0-14 and is a simple way of representing the hydrogen ion concentration of a solution and literally stands for negative logarithm of the hydrogen ion concentration
When the pH=7...
the solution is neutral, where the number of hydrogen ions and base ions are equal
When the solution has a pH lower than 7...
the solution is acidic, where hydrogen ions outnumber base ions
When the solution has a pH higher than 7...
the solution is basic or alkaline, where base ions outnumber hydrogen ions
Most body fluids are slightly...
basic pH: blood, intracellular-pH; inside cells is 7.2
A buffer is...
a chemical dissolved in a solution to maintain pH; converts a strong acid/base into a weak acid/base to make it affect the pH less
Salts can be dissolved in water to form cations and anions called...
electrolytes, which are capable of conducting an electrical current
A monomer is...
a single subunit of an organic compound in the body
A polymer is...
built from those monomer subunits
Dehydration synthesis is...
an anabolic reaction that links monomers together and makes a molecule of water in the process
Hydrolysis is...
a catabolic reaction that uses water to break up polymers into smaller subunits
Carbohydrates are composed of...
carbon, hydrogen, and oxygen
they function primarily as fuel in the body with some limited structural roles
Monosaccharides have...
from 3 to 7 carbons and are the monomers from which all carbohydrates are made
ex: glucose, fructose, galactose, and ribose/deoxyribose
Disaccharides are...
formed by union of two monosaccharides joined to one another by dehydration synthesis
Polysaccharides consist of...
many monosaccharides joined to one another by dehydration synthesis reactions
Glycogen is...
the storage polymer for glucose found mostly in skeletal muscle and liver cells
Some polysaccharides are found covalently bound to...
either proteins or lipids resulting in the following compounds: glycoproteins and glycolipids, which have various functions in the body
Lipids are...
a group of nonpolar hydrophobic molecules composed primarily of carbon and hydrogen, include fats and oils
Fatty acids are...
the basic lipid monomers consisting of 4 to 20 carbon atoms which may have none, one, or more double bonds between the carbons in the hydrocarbon chain
Saturated fatty acids are,..
solid at room temperature, and have no double bonds between carbon atoms
Monounsaturated fatty acids are...
generally liquid at room temperature, and have one double bond between two carbons in the hydrocarbon chain
Polyunsaturated fatty acids are...
liquid at room temperature, and have two or more separate double bonds between two carbons in the hydrocarbon chain
A triglyceride is...
three fatty acids linked by dehydration synthesis to a modified 3-carbon carbohydrate, glycerol
The storage polymer for fatty acids is called
a neutral fat
Phospholipids are...
composed of a glycerol backbone, two fatty acid "tails" and one phosphate group "head"
The term amphiphilic is for...
a phospholipid because they have a molecule with a polar group, a phosphate head, and a nonpolar group, and a fatty acid tail
-vital to the structure of cell membranes
Steroids are...
nonpolar and share a 4-ring hydrocarbon structure called the steroid nucleus
Cholesterol is,..
the steroids that forms the basis for all other steroids in the body; stabilizes the plasma membranes' fluid structure during temperature changes
Proteins are...
macromolecules that are involved in movement, function as enzymes, play structural roles, function in the body's defenses, and can be used as fuel
Amino acids are...
the monomers of all proteins, can be linked by peptide bonds in polypeptides
Peptides are...
formed when two or more amino acids are linked together by peptide bonds as a result of dehydration synthesis
What are the different types of peptides and how many amino acids do they have?
-dipeptides: 2 amino acids
-tripeptides: 3 amino acids
-polypeptides: 10 or more
A functional process consists of...
one or more polypeptide chains folded into distinct structures that must be maintained to be functional
Fibrous proteins are...
long, narrow strands that have a structural role
Globular proteins are...
more compact, rounded shaped and have functional roles
Primary protein structure is...
the sequence of a chain of amino acids
Secondary protein structure is...
local folding of the polypeptide chain into helices or sheets
Tertiary protein structure is...
3D folding pattern of a protein due to side chain interactions
Quaternary protein structure is...
proteins consisting of more than one amino acid chain
Protein denaturation is...
the disruption and destruction of both the secondary and tertiary structures; alters the protein shape by applying stress like heat, acid, or alkali
Nucleotides are...
the monomers of nucleic acid, make up our genetic material
The three parts of the nucleotide structure are...
-nitrogenous base with a hydrocarbon ring structure
-5-carbon pentose sugar, ribose or deoxyribose
-phosphate group
Purines are...
a double-ringer molecule
Adenine and Guanine
Pyrimidines are...
a single-ringed molecule
Cytosine, Uracil, and Thymine
Adenosine triphosphate is...
ATP; the main source of chemical energy in the body; adenine attached to ribose and three phosphate groups
ATP is synthesized from...
ADP and a phosphate group using energy from the oxidation of fuels such as glucose; requires oxygen
DNA and RNA are...
the two main nucleic acids that are responsible for the storage and execution of the genetic code
DNA is...
an extremely large molecule found in the nucleus of the cell, composed of two long chains that twist around each other to form a double helix held together by hydrogen bonds between the bases
-DNA contains the genes that provide the recipe or code for protein synthesis, the process of making every protein in the body
What are the base pairings
A to T (2 hydrogen bonds)
G to C(3 hydrogen bonds)
RNA is...
a single strand of nucleotides, can move between the nucleus of a cell and its cytosol and is critical to the making of proteins
-A to U
Transcription is...
DNA to RNA
Translation is...
RNA to proteins
Cell metabolism is...
the sum of all chemical reactions that a cell carries out to maintain life
Transport of substances means that...
the cell has produced or ingested to a variety of destinations is a vital process
Communication in a cell is...
between cell and itself, its surrounding environment, and other cells is carried out by various methods including chemical and electrical signals
Cell reproduction includes...
cell division-process that is necessary for growth and development and for replacement of old and damaged cells
What are the three basic components of animal cells?
-plasma membrane
-cytoplasm
-nucleus
The plasma membrane...
surrounds each cell, isolating its internal structures and processes from the external environment
What are the functions of the plasma membrane?
it provides the cell with structural support, means of communication with its surrounding and other cells, and cell identification
What does the plasma membrane separate?
The intracellular space with the intracellular fluid (ICF), or cytosol, and then extracellular space with the extracellular fluid (ECF)
Cytoplasm inside of the cell consists of...
both the fluid cytosol and the organelles and the cytoskeleton embedded within it
Cytosol is...
mostly water with dissolved solutes, inclusions or storage molecules, and proteins and is the site of many important chemical reactions
intracellular fluid
Organelles are...
a variety of cellular machines with very specific functions that are suspended in the cytosol, and serve to separate the potentially damaging chemical reactions from the surrounding cell structures known as compartmentalization
The cytoskeleton consists of...
a network of protein filaments that supports the cell by creating and maintaining its shape, holding the organelles in place and providing a means of transportation for substances within the cell
The nucleus is...
a single roughly spherical organelle enclosed in a phospholipid bilayer similar to the plasma membrane (nuclear envelope)
The nucleus contains...
most of the cell's DNA and is the primary location for making most of the RNA
In the phospholipids bilayer...
-molecules must have parts that interact with water in both fluid compartments without falling apart
-molecules must have parts that repel water, keeping ECF and cytosol separated
The fluid mosaic model is...
not all the same thing; plasma membranes are dynamic fluid structures with multiple components, some with the ability to move within bilayer as phospholipids move themselves
Integral proteins can...
span the entire plasma membrane and are called transmembrane proteins when they travel through both layers of the plasma membrane
Peripheral proteins are...
found only on one side of the plasma membrane or the other
Glycolipids and glycoproteins...
serve to identify the cell as part of the body or for cell recognition
A selectively permeable membrane is...
allowing certain molecules to cross it while prohibiting passage of other molecules
Passive transport...
does not require the expenditure of energy
Active transport...
does require energy (ATP) to move substances against their concentration gradient using pumps
The three variables that determine how a substance is able to move across the plasma membrane are...
-type of substance
-plasma membrane permeability to substance
-concentration of substance in cytosol and EFC
Diffusion is...
the net movement of molecules down a concentration gradient
simple diffusion involves...
mostly nonpolar solutes like oxygen, carbon dioxide, lipids, and hydrocarbons that are able to pass straight through the bilayer without membrane proteins
Facilitated diffusion involves...
charged or polar solutes such as ions and glucose that cross the bilayer with the help of membrane proteins, either a carrier or a channel
Osmosis is...
a passive process in which a solvent moves across a membrane to an area with a higher concentration of solute to lower; water from low to high
Osmotic pressure is...
the driving force exerted by solute molecules that causes water molecules to move from a higher solute to lower solute concentration
Tonicity is...
a way to compare the osmotic pressure gradient between two solutions, the cytosol and ECF in the body
Isotonic ECF means...
both fluids have approximately the same concentration of solute, so there is no net movement of water across the membrane and no volume changes
Hypertonic ECF causes...
water to leave the cell; the cell shrivels/crenates
Hypotonic ECF causes...
water to enter the cell; the cell swells and possibly rupture or lyse
Primary active transport involves...
a pump in the plasma membrane that binds and transports a solute against its concentration gradient using ATP; sodium potassium pump
Secondary active transport uses...
ATP indirectly to fuel a transport pump
Electrical potential is...
created by a separation of charged that causes an electrical gradient
-has the possibility of providing energy to do work
Membrane potential is...
the electrical potential found across a plasma membrane
Vesicles are...
small sacs filled with large molecules too big to transport by other means
Endocytosis is...
the transport of ECF, large molecules, and whole cells into the cell
-phagocytosis, pinocytosis, and receptor-mediated endocytosis
Exocytosis is...
the process where large molecules exit the cell, known as secretion, when vesicles fuse with the plasma membrane
What are the organelles that are separated from the cytosol (compartmentalization) and considered cellular machinery with specific functions to maintain homeostasis?
mitochondrion, peroxisomes, endoplasmic reticulum, and golgi apparatus
What are the organelles that are NOT separated from the cytosol (compartmentalization) and considered cellular machinery with specific functions to maintain homeostasis?
ribosomes and centrosomes
Mitochondria are...
the power plant of the cell, membrane-bound organelles that provide a majority of ATP in a cell
Each mitochondrion has its own...
DNA, the enzymes and organelle involved in protein synthesis and ribosomes
The mitochondrion has a double bilayer structure with...
a smooth outer membrane and an inner membrane that is highly folded into cristae
Each membrane and the two spaces they create have...
their own unique enzymes and proteins required to perform their specific functions
The matrix contains the...
mitochondrial DNA, proteins, and enzymes specific for the breakdown of organic fuels by oxidative catabolism to produce ATP that requires oxygen.
Peroxisomes, a membrane-bounded organelle, use...
oxygen to carry out several chemical reactions that produce hydrogen peroxide
Ribosomes are...
tiny, granular, nonmembrane bound organelles where protein synthesis takes place
-made of rRNA
Where are ribosomes found within the cell? What function(s) do ribosomes serve in these locations?
-Free in cytosol- usually make proteins needed within cell itself
-Bound to membranes of other cellular structures- produce proteins destined for export outside cell, for export to lysosomes, or for insertion into a membrane
The organelles of the endomembrane system form...
vesicles that exchange
proteins and other molecules.
The members of the system...
synthesize, modify, and package molecules produced within the cell
The endoplasmic reticulum (ER) is...
a large, folded phospholipid bilayer continuous with the nuclear envelope, exists in two forms: the rough ER (RER) has ribosomes bound to it and the smooth ER (SER) does not.
Rough endoplasmic reticulum has...
ribosomes bound to its membrane.
-Most proteins that enter the RER are for transport out of the
cell.
-The RER produces membrane components for the membrane bound organelles and the plasma membrane including the integral and peripheral proteins.
The RER packages secretory proteins into transport vesicles
made of a phospholipid bilayer that is sent to the...
golgi apparatus for further processing
Smooth endoplasmic reticulum (SER) is not associated with ribosomes and has essentially no role in protein synthesis, but does perform the
following vital functions...
-stores calcium ions by pumping them out of cytosol for future use
-capable of several detox reactions; limits damage caused by certain substances
-involved in lipid synthesis, manufacturing majority of plasma membrane phospholipids and cholesterol as well as a number of lipoproteins and steroid hormones
The Golgi apparatus, located between the RER and the plasma membrane, is...
a group of flattened membranous sacs filled with enzymes and other molecules
Proteins and lipids made by the ER are...
further modified, sorted, and packaged for export in the Golgi apparatus.
-sent to lysosomes, plasma membrane, or secreted from exocytosis
Lysosomes are....
the organelles responsible for digestion of worn out cell components, or whole cells in some cases
The SER makes _______ and the RER makes ______, and each product is packaged into vesicles for transport to the ________.
lipids
proteins
golgi apparatus
The Golgi...
sorts and further modifies both lipids and proteins and packs them into vesicles, which may take one of three pathways once they exit the Golgi apparatus.
The cytoskeleton, made of several types of protein filaments, is...
a dynamic structure able to change its function based on the needs of the cell.
The functions of the cytoskeleton include...
-giving the cell its characteristic shape and size
-supporting the plasma and nuclear membranes as well as the organelles
-functioning in movement and performing specialized functions in different cell types
The cytoskeleton contains
three types of long protein filaments composed of smaller protein subunits
that allow for rapid disassembly and reassembly called...
actin filaments, intermediate filaments, and microtubules
Cellular extensions
are...
formed by the inner framework of the cytoskeleton
The three extensions are...
microvilli, cilia, and flagella
Microvilli are...
finger-like extensions of plasma membrane with actin filament core to help maintain shape; example of Structure-Function Core Principle; increase surface area of cells in organs specialized for absorption
Cilia are...
hairlike projections composed of microtubules and motor proteins; move in unison to propel proteins past the cell; found in great numbers on each cell
Flagella are...
solitary; longer than cilia; found only on sperm cells; beat in a whiplike fashion propelling entire cell
The nucleus is...
the governing body that directs the activities of the other cellular components and largely determines the type of proteins and the
rate at which the cell makes them
The DNA housed in the nucleus contains...
the code, or plans,
called genes for nearly every protein in the body.
Genes found within the DNA are executed by....
several different types of RNA to build a wide variety of proteins
What are the three main structures of a nucleus?
nuclear envelope, nucleoli, chromatin
The nuclear envelope is...
a double phospholipid bilayer that surrounds and encloses the entire contents of the
nucleus.
Nuclear pores serve...
to connect the nucleoplasm with the cytoplasm, allowing substances to move between the two locations.
Chromatin consists of...
one extremely long DNA molecule and its associated proteins that organize and fold the molecule to conserve space
the nucleosome consists of...
a strand of DNA coiled around a group of
histone proteins that appears like a bead on a string. This structural
arrangement reduces the length of the strand by about one-third.
During periods of cell division, chromatin threads coil tightly and
condense into thick structures called...
chromosomes
human cells contain _____ pairs of chromosomes (1 maternal and 1 paternal)
23
Identical copies of each chromosome made in preparation for
cell division, known as _______, connect to one
another at a region called the _______.
sister chromatids
centromere
Nucleoli: The nucleolus (plural, nucleoli) is...
a region in the nucleus
responsible for the synthesis of ribosomal RNA and the assembly of ribosomes.
Protein synthesis is...
The process of manufacturing proteins from DNA blueprint using RNA
Gene expression is...
The production of a protein from a specific gene
Transcription is...
process where gene for specific protein is copied; creating messenger RNA; exits through nuclear pore
-the process of making
mRNA copies of DNA, called a transcript, which can exit the nucleus through a nuclear pore.
Translation occurs...
in cytosol; mRNA binds with ribosome initiating synthesis of a polypeptide consisting of a specific sequence of amino acid
-at the ribosome where the
nucleotide sequence of mRNA is translated into an amino acid sequence
with the help of transfer RNA (tRNA).
Summary of the process of protein synthesis
DNA--> transcription-->mRNA-->translation-->protein
A gene is...
a long chain of
nucleotides is a specific segment of DNA that determines the sequence of
amino acids in a protein.
There are only four nucleotides in DNA (A, , C, G and T ). It takes
several combinations of three nucleotides called...
a triplet to represent
the 20 different amino acids. Each amino acid is represented by one or more of these triplets.
A triplet is...
a 3-nucleotide sequence of mRNA
During transcription, each DNA triplet is transcribed into a
complementary RNA copy, a 3-nucleotide sequence of mRNA
During translation at a ribosome, each codon is paired with a
complementary tRNA called an
anticodon
The mRNA transcript is built with the help of the enzyme...
RNA polymerase, which binds to a gene and brings in complementary
nucleotides linking them together to form mRNA.
What are the three stages of both transcription and translation
initiation
elongation
termination
tRNA, made in the nucleus, picks up specific amino acids and transfers them to a...
ribosome
The newly formed polypeptide must...
be modified, folded properly, and sometimes combined with other polypeptides to become a fully functional protein.
Cell theory is...
a biological principle that states that cells cannot spontaneously appear, but rather, they must come from the division of
cells that already exist. All forms of life, including humans, are the result
of repeated rounds of cell growth and division
The cell cycle is...
ordered series of events from formation of cell to its reproduction by cell division
Cell division is required...
for growth and development as well as for tissue repair and renewal
The two main phases of the cell cycle are...
interphase and Mphase
Interphase is...
a period of growth and preparation for cell division,
includes the following three subphases: G1, S, and G2.
G1 phase is...
(first gap) the period where a cell performs its
normal daily metabolic activities. Production of new
organelles, cytoskeleton, and other vital proteins highlight this phase.
S phase is...
(synthesis) the period where DNA synthesis (replication) occurs. Chromatin unwinds and each base pair is duplicated using an existing DNA strand as a template to build a new strand
The steps of DNA replication are...
1. DNA strands are separated by the enzyme helicase
2. The enzyme primase builds an RNA primer on the exposed
DNA strands.
3. The enzyme DNA polymerase adds nucleotides to the RNA primer, which is necessary as the enzyme is only able to add to an existing chain of nucleotides.
4. DNA polymerase proceeds in opposite directions along
each strand as helicase separates them. The RNA primers are eventually removed and replaced with DNA
nucleotides.
5. Finally, two identical double helices, each with one old
and one new strand, are made during semiconservative
replication
G2 phase is...
(second gap) another period of cellular growth where proteins required for cell division are produced and centrioles are duplicated.
M phase is...
the period of cell division and is highlighted by two
overlapping processes: mitosis and cytokinesis
- The nucleus and nucleolus are clearly visible during interphase, and the individual chromosomes are not distinguishable
-However, at the beginning of mitosis, the nucleus and nucleolus disappear and the chromosomes become apparent.
mitosis is...
the division of genetic material
Prophase is...
the first stage where
-chromatin condenses so sister chromatids are visible
-nucleolus disperses,
-mitotic spindle forms and in late prophase spindle fibers attach to sister chromatids
-two centriole pairs separate and begin migrating to opposite poles of the cell
-nuclear envelope fragments
Metaphase is...
the second and longest stage where
-spindle fibers pull sister chromatids to align on equator of cell
Anaphase is...
the third stage where
-sister chromatids separate as spindle fibers shorten; daughter chromosomes are pulled to opposite poles; cell elongates; cytokinesis begins as organelles and cytosol are divided
Telophase is...
the fourth and final stage where
- nuclear envelope reassemble; nucleoli re-form; chromosomes are no longer distinct- DNA returns to chromatin form
Cytokineses is...
where the cleavage furrow forms, daughter cells separate
The cell cycle is precisely controlled so that...
cell formation is balanced with cell death.
Cell cycle control and checkpoints are for...
1. During the cell cycle, checkpoints act as stop/go signals for the cell.
2. The cell responds to a variety of extracellular signals that determine if
the conditions are for division are unfavorable. The cell may not
proceed with division if the following conditions are not favorable.
3. Cells that cannot pass through the checkpoints and cannot be repaired
undergo a process of programmed cell death called apoptosis.
If cell cycle control is lost ________ may result, which is
uncontrolled cell division resulting in a tumor
cancer
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