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388 terms

IB Biology HL Final Exam 2011

STUDY
PLAY
Normal Distribution
Most variation in data gives a bell-shaped frequency distribution called .......
Standard Deviation
Used to asses how far the values are spread above and below the mean.
t-Test
Used to find out whether there is a significant difference between the means of two populations.
Functions of life
Metabolism
Response
Homeostasis
Growth
Reproduction
Nutrition
Cell Theory
-Living organisms are composed of cells
-Cells are the smallest units of life
-Cells come from pre-existing cells
Exceptions to the cell theory
-muscle fibers
-hyphae
-extracellular material
Differentiation
How cells in a multicellular organism can develop in different ways.
Emergent properties
The whole organism is greater than the sum of it's parts, because of the complex interactions between cells.
Stem cells
Cells that have the capacity to self-renew by cell division and to differentiate.
Surface area to volume ratio
As the size of any object increases, the ratio between the surface area and the volume decreases.
Magnification
Size of image / size of specimen
Scale bar
A line added to a micrograph or drawing to help show the actual size of the structures.
Binary fission
Prokaryotic cells divide in two by a process called ......
Integral proteins
Proteins embedded in the phospholipid bilayer
Peripheral proteins
Proteins on the surface of the membrane.
Fluidity
This allows membranes to change shape in a way that would be impossible if they were solid.
Hormone binding sites
A site exposed on the outside of the membrane that allows one specific hormone to bind.
Diffusion
The passive movement of particles from a region of high concentration to a region of low concentration.
Facilitated diffusion
Diffusion of particles with the aid of channel proteins.
Solvent
A liquid in which particles dissolve.
Solute
Dissolved particles.
Osmosis
The diffusion of water.
Active transport
The movement of substance across membranes using energy from ATP.
Extracellular components
The plant cell wall and glycoproteins are examples of .....
Interphase
The longest stage in the cell cycle.
G1
During interphase, a period of growth and DNA transcription/ protein synthesis.
S phase
During interphase, the period during which all DNA in the nucleus is replicated.
G2
During interphase, the period in which the cell prepares for division.
Mitosis
The process by which the nucleus divides to form two genectically identical nuclei.
Cytokinesis
The process of splitting the cytoplasm to to form two cells.
4 stages of mitosis
-prophase
-metaphase
-anaphase
-telophase
Tumour
This is formed when cells divide out of control.
Cell cycle
The series of events that produces new cells.
Water
Two hydrogen atoms bonded to an oxygen atom.
Hydrogen bond
The type of bond between water molecules and between base pairs in DNA.
Properties of water
-cohesion
-solvent
-heat capacity
-boiling point
-cooling effect/evaporation
Commonest chemical elements of life
Carbon, oxygen, hydrogen, nitrogen
Organic compounds
Compounds containing carbon that are found in living organisms.
Inorganic compounds
Compounds that contain no carbon.
Sulphur
Needed to make two of the twenty amino acids that proteins contain.
Calcium
Helps the body to produce strong bones and teeth.
Phosphorous
Part of the phosphate groups in ATP and DNA molecules.
Iron
Needed to make cytochromes and oxygen-binding sites on hemoglobin.
Sodium
Helps with nerve impulses and solute concentrations within cells.
Polypeptide
A chain of many amino acids.
Triglyceride
Three fatty acids and a glycerol.
Hydrolysis reaction
The reverse of a condensation reaction.
Examples of monosaccharides
Glucose, galactose, fructose
Examples of disaccharides
Maltose, lactose, sucrose
Examples of polysaccharides
Starch, glycogen, cellulose
Functions of lipids
-energy storage
-insulation
-buoyancy
Nucleotide
A sugar, phosphate and base.
Complementary base pairing
In DNA:
A - T
C - G
Semi-conservative model
Each DNA molecule consists of one new strand and one old strand conserved from the parent dna molecule
Genes
These store the information for making proteins.
Transcription
The copying of the base sequence of a gene by making and RNA molecule.
Translation
When tRNA creates proteins on a ribosome.
Codon
A group of three bases.
Enzymes
Globular proteins which act as catalysts of biological reactions.
Denaturation
Changing the structure of an enzyme or other protein so that it can no longer carry out it's function.
Substrates
The reactants in reactions catalyzed by enzymes.
Active site
A region on the surface of an enzyme to which substrates bind.
Lock and key theory
Theory explaining enzyme specificity.
Factors that affect enzyme activity
Substrate concentration, pH, temperature.
Lactose
Glucose plus galactose.
Cellular respiration
A controlled release of energy, in the form of ATP, from organic compounds in cells.
Measuring rates of photosynthesis
-production of oxygen
-uptake of carbon dioxide
-increases in biomass
Genetics
The study of variation and inheritance
Gene
A heritable factor that controls a specific characteristic.
Genome
The whole of the genetic information of an organism.
Gene locus
The position of a gene on a chromosome.
Allele
A form of a gene.
Gene mutation
A change to the base sequence of a gene.
Base substitution
Smallest possible gene mutation when one base is replaced by another base.
Example of a base substitution
Sickle cell anemia
Diploid
Two full sets of chromosomes.
Haploid
One set of chromosomes.
Homologous chromosomes
Chromosomes that have the same genes as each other, but not necessarily the same alleles.
Reduction division
Meiosis is deceived as a ......
Karyotype
The number and appearance of the chromosomes in an organism.
Amniocentesis
A sample of amniotic fluid is removed from the amniotic sac for karyotyping.
Chorionic villus sampling
Cells are removed from fetal tissues in the placenta for karyotyping.
Non-disjunction
Non-separation of chromosomes.
Down syndrome
An extra 21st chromosome.
Homozygous
Having two identical alleles of a gene.
Heterozygous
Having two different alleles of a gene.
Dominant allele
An allele that has the same effect on the phenotype in a heterozygous individual and in a homozygous individual
Recessive allele
An allele that only has an effect on the phenotype in a homozygous individual.
Segregation
When the F1 hybridsroduce gametes, the two alleles separate.
Female
XX
Male
XY
Sex linkage
The association of a characteristic with gender, because the gene controlling the characteristic is located on a sex chromosome.
Carrier
When a person has a recessive of an allele of a gene but it does not affect the phenotype because a dominant allele is also present.
Test cross
An individual that might be heterozygous is crossed with an individual that is homozygous recessive.
PCR
When DNA is copied again and again to produce many copies of the same molecule.
Gel electrophoresis
A method of separating mixtures of proteins, DNA or other molecules that are charged.
Genetically modified organisms
Organisms that have genes transferred to them.
Clone
A group of genetically identical organisms or a group of genetically identical cells derived from a single parent cell.
Species
A group of organisms with similar characteristics which can interbreed and produce fertile offspring.
Nomenclature
The naming of species
Genus
Species that are similar are grouped into a ....
Family
Genera that are similar are grouped into a ....
Order
Families that are similar are grouped into an ....
Class
Orders that are similar are grouped into a ....
Phylum
Classes that are similar are grouped into a .....
Kingdom
Phyla that are similar a grouped into a ....
Bryophytes
Mosses
Filicinophytes
Ferns
Coniferophytes
Conifers
Angiospermophytes
Flowering plants
Porifera
No clear symmetry, attached to a surface, pores through body, no mouth or anus
i.e. Sponges
Platyhelminths
Bilaterally symmetric, flat bodies, unsegmented, mouth but no anus
i.e. Planaria, tapeworms, liverflukes
Mollusca
Muscular foot and mantle, shell usually present, segmentation not visible, mouth and anus
i.e. Slugs, snails, clams, squids
Cnidaria
Radially symmetric, tentacles, stinging cells, mouth but no anus
i.e. Jellyfish, corals, sea anemones
Annelida
Bilaterally symmetric, bristles often present, segemented, mouth and anus
i.e. Earthworms, leeches, ragworms
Arthropoda
Bilaterally symmetrical, exoskeleton, segmented, jointed appendages
i.e. Insects, spiders, crabs, milipedes
Natality
Offspring are produced and added to the population.
Mortality
Individuals die and are lost from the population.
Immigration
Individuals move into the area from elsewhere and are added to the population.
Emigration
Individuals move out of the area to live elsewhere.
Population change
(natality + immigration) - (mortality + emigration)
Evolution
The cumulative change in the heritable characteristics of a population.
Evidence for evolution
Homologous anatomical structures, fossil records, selective breeding of domesticated animals.
Natural selection
The better adapted individuals tend to survive and reproduce more than the less well-adapted individuals.
Variation
Essential for natural selection and therefore for evolution.
Example of evolution in action
Multiple antibioticcresistance in bacteria.
Community
A group of populations living together and interacting with each other in an area.
Trophic levels
Position of an organism in the food chain.
Autotrophs
Organisms that synthesize their own organic molecules from simple inorganic substances.
Heterotrophs
Organisms tht obtain organic molecules from other organisms.
3 types of heterotrophs
Consumers, detritivores, saprotrophs
Light
Initial energy source
Consumers
Organisms that ingest organic matter that is living or recently killed.
Detritivore
Heterotroph that invests dead organic matter.
Saprotrophs
Heterotroph that lives on or in dead organic matter, secreting enzymes into it and absorbing the products of digestion.
Food web
A diagram that shows all the feeding relationships in a community.
Energy pyramids
Diagrams that show how much energy flows through each trophic level in a community.
Ecosystem
A community and it's abiotic environment.
Ecology
The study of relationships in ecosystems.
Greenhouse gases
Carbon dioxide, methane, oxides of nitrogen, sulfur dioxide.
Greenhouse effect
Heat retention by greenhouse gases in the atmosphere.
Global warming
Greenhouse effect and it's correlation with rising temperatures on earth.
Habitat
The environment in which a species normally lives or the location of a living organism.
Amylase
Source: salivary glands
Substrate: starch
Products: maltose
pH: 7
Protease
Example: pepsin
Source: wall of stomach
Products: small polypeptides
pH: 1.5
Lipase
Source: pancreas
Products: triglycerides
pH: 7
Absorption
Happens in the small intestine.
Assimilated
After food becomes absorbed, it becomes .....
Villus
Structure that absorbs in small intestine.
Digestive path
Mouth, esophagus, stomach, small intestine, large intestine, rectum, anus.
Myogenic
Contraction of the heart is .... Because it can contract on it's own.
Arteries
Thick layers of circular elastic and muscle fibers, narrow lumen, thick wall to withstand high pressures.
Veins
Thin walled, wide lumen, valves to prevent back flow.
Capillaries
Wall consists of a single layer of cells, allows for easy diffusion, very narrow lumen.
Heartbeat
Atria contract, blood flows into ventricles, semilunar valves close, ventricles contract, atrioventricular valves close, blood flows into arteries
Pacemaker
Sinoatrial node
Composition of blood
Plasma, erythrocytes, leukocytes, playelets.
Phagocytes
These cells can identify pathogens and ingest them by endocytosis.
Pathogen
An organism or virus that causes disease.
Functions of blood
Transport and defense against infectious disease
What plasma transports
Nutrients, carbon dioxide, hormones, antibodies, urea.
Barriers to infection
Skin and muscous membranes
Antibiotics
Chemicals produced by microorganisms to kill or control the growth of other microorganisms.
Lymphocytes
Antibodies are made by ....
AIDS
Caused by the human immunodeficiency virus (HIV)
Gas exchange
The process of swapping one gas for another.
Ventilation
The process of bringing fesh air to the alveoli and removing stale air.
Adaptations of the alveolus
Huge surface area for gas exchange, wall consists of thin layer of cells, covered by capillaries, surfactant is released to allow gases to dissolve.
Inhalation
External intercostal muscles contract,diaphragm contracts, volume in thorax is increased, pressure drops, air flows in.
Exhalation
Internal intercostal muscles contract, abdominal muscles contract, volume of thorax is decreased, pressure is increased, air flows out
2 parts to the nervous system
Central nervous system and peripheral nervous system
Sensory neurons
Neurons that carry impulses from receptors to the central nervous system
Motor neurons
Neurons that carry impulses from the central nervous system to effectors.
Relay neurons
Neurons that carry impulses within the central nervous system.
Synapse
A junction between two neurons.
Synaptic cleft
Narrow, fluid -filled space between two neurons.
Neurotransmitters.
Chemicals that are passed along the synapse.
Stages in synaptic transmission
Nerve impulse reaches end of pre-synaptic neuron, calcium diffused in through calcium channels, vesicles of neurotransmitters move to membrane and release their contents, neurotransmitters diffuse across synaptic cleft and binds to receptors, sodium ions enter post-synaptic neuron and cause depolarization, nerve impulse sets off along the post synaptic neuron, calcium is pumped out of pre-synaptic neuron and maiming neurotransmitters are broken down or absorbed.
Resting potential
The electrical potential across the plasma membrane of a cell that is not conducting an impulse.
Action potential
The reversal and restoration of the electrical potential across the plasma membrane of a cell, as an electrical impulse passes along it.
Depolarization
When the potential across the membrane is reversed.
Repolarization
When the potential across the membrane is restored.
Homeostasis
Maintaining the internal environment of the body between limits.
Negative feedback
A rise in levels feeds back to decrease production and reduce this level.
Positive feedback
A rise in levels feeds back to increase production and increase this level.
Beta cells
These cells produce insulin.
Alpha cells
These cells produce glucagon
Diabetes
A disease in which the contro, of blood glucose does not work effectively and the concentration can rise or fall beyond the normal limits.
Pituitary gland
FSH and LH are produced by the .....
FSH
Stimulates the development of follicles in females.
Follicle
Fluid-filled sacs that contain and egg cell.
LH
Stimulates follicles to become mature, ovulate and then develop into the corpus luteum.
Testosterone
Male sex hormone.
Okazaki fragments
Short lengths of DNA that are formed between RNA primers.
Helicase
Uncoils the DNA double helix and splits it into two template strands.
DNA polymerase
Adds nucleotides in a 5' to 3' direction.
Ligase
Glues dna fragments back together.
Rna primase
Adds a short length of rna to template strand during DNA replication.
Introns
Sequences of bases that are transcribed but nit translated.
Exons
Sequences of bases that are transcribed and translated.
Nucleosome
Globular structures that contain eight histone proteins, with dna wrapped around it.
Antisense strand
The strand if DNA that forms the template.
Sense strand
The strand of DNA that the template is formed from.
Free ribosomes
Ribosomes in the cytoplasm.
Bound ribosomes
Ribosomes attached to the rough endoplasmic reticulum.
Polysome
A group of ribosomes moving along the same mRNA as they simultaneously translate it.
3 steps of translation
Initiation, elongation, termination
Primary protein structure
The number and sequence of amino acids in a polypeptide.
Secondary protein structure
Regular peating structures including beta- pleated sheets and alpha- helices.
Tertiary protein structure
The three dimensional conformation if a polypeptide.
Quaternary protein structure
The linking together of two or more polypeptides to form a single protein.
Fibrous proteins
Long and narrow proteins.
Globular proteins
Rounded shaped proteins.
Examples of fibrous proteins
Myosin and collagen
Examples of globular proteins
Hemoglobin and immunoglobulin
Induced fit theory
If the shape of an active site alters when substrates bind, several different but similar substrates could bind successfully to it.
Enzyme inhibitors
Chemicals that reduce the activity of enzymes or even stop it completely.
Competitive inhibition
substrate and inhibitor are chemically similar, inhibitor binds to active site, prevents the substrate from binding to enzyme therefore the activity of the enzyme is prevented.
Nn-competitive inhibition
Substrate and inhibitor are not similar, inhibitor binds to enzyme at different site, inhibitor changes conformation of enzyme but substrate may still be able to bind to active site
End-product inhibition
The product of the last reaction in the pathway inhibits the enzyme that catalyzed the first reaction.
Allosteric enzyme
Enzymes that have two non-overlapping binding sites, one of which is the active site.
Glycolysis
One glucose is converted into two pyruvate, there is a net yield of 2 ATP molecules, 2 NAD+ are converted into 2 NADH + H+
Link reaction
Pyruvate from glycolysis is absorbed by the mitochondrion, oxidative decarboxylation occurs on pyruvate and Acetyl CoA is produced.
Krebs cycle
Acetyl CoA is transferred to oxaloacetate to form citrate which is eventually turned back to oxaloacetate. Cycle happens twice and yields 2 ATP
Oxidative phosphorylation
When ATP production relies on energy released by oxidation.
Chemiosmosis
The coupling of ATP synthesis to electron transport via a concentration gradient of protons.
Electron transport chain
Located in mitochondrial inner membrane, NADH and FADH2 feed electrons into the chain, at the end of the chain, the remaining electrons are given to oxygen. Oxygen accepts these electrons as well as hydrogen ions to create water and yields 30 ATP. The only stage in cellular respiration that uses oxygen.
ATP synthase
Located in the inner mitochondrial membrane, it transports the protons back across the membrane down the concentration gradient.
Photosynthesis
The process that plants, algae and some bacteria use to produce all of the organic compounds that they need.
Action spectrum
A graph that shows that violet and blue light are used most efficiently.
Absorption spectrum
A graph showing the percentage of the wavelengths of visible light that are absorbed by two common forms of chlorophyll.
Wavelengths of light most efficient for photosynthesis
Red and blue wavelengths
Excited electron
An electron at a higher energy level.
Thylakoid membranes
Where chlorophyll is located.
Non-cyclic photophosphorylation
The production of ATP using the energy from an excited electron from photosystem 2.
Photolysis
The splitting of water molecules during photosynthesis.
Oxygen
The product of photolysis.
Carbon dioxide
Essential substrate in the light-independent reactions.
Light-dependent and light - independent reactions
Two reactions in photosynthesis.
Limiting factors of photosynthesis
Light intensity, carbon dioxide concentration, temperature.
Palisade mesophyll
Densely packed cylindrical cells with many chloroplasts.
Transpiration
The loss of water vapour from the leaves and stems of plants.
Spongy mesophyll
Consists of loosely packed cell with few chloroplasts. Provides main gas exchange surface in plants.
Stomata
Pores that allow carbon dioxide to flow into the plant and oxygen to flow out. Normally found on the underside of the leaf.
Guard cells
Pair of cells that can open or close the stoma.
Xylem
Brings water to replace losses due to transpiration.
Phloem
Transports products if photosynthesis out of the leaf.
Absisic acid
This hormone causes guard cells to close the stomata.
Factors that effect transpiration rate
Light, temperature, humidity, wind
Xerophytes
Plants that are adapted to grow in very dry habitats.
Roots
They absorb water and mineral ions from the soil.
Transpiration stream
When transpiration is occurring, water moves upwards from the roots to the leaves.
Transpiration pull
Low pressure or suctn is created inside xylem vessels when water is pulled out.
Active translocation
When sugars and amino acids are transported inside plants via phloem tissue.
Source to sink
Sugar and amino acids are transported through the phloem from ..... to ......
Pollination
The transfer of pollen from an anther to a stigma.
Anther
Male part of a flower
Stigma
Female part of a flower
Filaments
Holds up anthers.
Style
Holds up stigma.
Factors need fir seed germination
Water, oxygen, suitable temperatures
Steps of germination
Absorption of water, production of gibberellin in cotyledons, gibberellin stimulates production of amylase,amylase catalyses digestion of starch into maltose, maltose converted inti glucose which provides the seed with energy.
Characteristics of a monocotyledon plant
Leaf veins run parallel, vascular bundles in stem are spread randomly, organs of flower in multiples of 3, unbranched roots.
Cotyledon
The leaves the the embryo plant has.
Monocotyledon
One cotyledon.
Dicotyledon
Two cotyledons.
Characteristics of a dicotyledon plant
Leaf veins in net-like pattern, vascular bundles are in ring in stem, organs in multiples of 4 or 5, branched roots.
Meristems
Regions in plants where cells continue to divide and grow.
Apical meristems
Meristems at the tip of the root and the tip of the stem. Allows for elongation.
Lateral meristems
Usually the cambium in a dicotyledon plant. Allows for growth in girth.
Auxin
A plant hormone which acts as a growth promoter.
Phytochrome
A pigment in leaves which exists in two forms that allows the plant to measure the lengths of periods of darkness.
Ratio for heterozygous dihybrid cross
9:3:3:1
Ratio for heterozygous monohybrid cross
3:1
Polygenic inheritance
Characteristics that are influenced by more than one gene.
Gene linkage
When some pairs of genes do not follow the law of independent assortment and combinations if genes tend to be inherited together.
Crossing over
While the chromosomes are paired during meiosis, sections of chromatid are exchanged.
Meiosis
Involves two divisions to form four cells, chromosome number is halved, the is an almost infinite amount of genetic variety.
8 stages of meiosis
Prophase1, metaphase1, anaphase 1, telophase 1, prophase 2, metaphase 2, anaphase2, telophase 2.
Stages in antibody production
Antigen presentation, activation of helper T-cells, activation of B-cells, production of plasma cells, production of memory cells
Antigen presentation
Macrophages take in antigens by endocytosis, process them and the attach them to membrane proteins called MHC proteins. The antigens are then displayed on the outside if the macrophage.
Activation of helper T-cells
Helper T-cells have receptors that can bind to antigens presented by macrophages. The helper T-cells bind to the antigens and the macrophage passes a signal to them changing them from inactive to active.
Activation of b-cells
The activated helper T-cell sends a signal to the b-cell causing it to change from inactive to active.
Immunity
Resistance to infection.
Active immunity
Due to the production of antibodies by the organism itself after the body's defense mechanisms have been stimulated by antigens.
Passive immunity
Due to the acquisition of antibodies received from another organism, in which active immunity has been stimulated.
Platelets
Small cell fragments that circulate with erythrocytes and leukocytes in the blood plasma.
Tendons
These attach muscle to bone.
Bones
These provide a firm anchorage for muscles.
Ligaments
These connect bone to bone.
Cartilage
This reduces friction between bones where they meet.
Synovial fluid
This lubricates the joint to reduce friction.
Joint capsule
This seals the joint and holds in the synovial fluid.
Myofibrils
Within each muscle fibre a cylindrical structures called .....
Sarcomeres
Subunit of a myofibril.
Dark band
The part of the sarcomere containing myosin.
Light band
The part of the sarcomere containing actin.
Actin
Thin muscle filaments.
Myosin
Thick muscle filament with heads.
Z lines
The places where actin and myosin are attached.
Functions of the kidney
Excretion and osmoregulation.
Excretion
The removal from the body of the waste products of metabolic pathways.
Osmoregulation
The control of the water balance of the blood, tissue or cytoplasm of w living organism.
Glomerulus
Produces filtrate.
Ultrafiltration
The production of filtrate from blood.
Nephron
The functional unit of the kidney.
Selective re-absorption
This mostly happens in the proximal convoluted tubule
Spermatogenesis
The production of spermatozoa. (4)
Seminiferous tubules
Spermatogenesis occurs here.
Leydig cells
These cells secrete testosterone
Oogenesis
The production of an ovum. Occurs in the ovary. Produces one good ova and 3 polar bodies.
Stages in the fertilization of a human egg
Arrival of sperm, binding, acrosome reaction, fusion, cortical reaction, mitosis.
Acrosome reaction
When the contents of the acrosome are released and proteases digest a route for the sperm.
Cortical reaction
Cortical granules move to the plasma membrane of the egg and fuse with it. Enzymes are released and prevents the entry of more sperm.
Copulation
Biological term for sexual intercourse.
Fertilization
The fusion of an egg with a sperm.
Progesterone
The end of pregnancy is signal led by the fall of this hormone.
Oxytocin
This hormone causes the muscle in the uterus wall to contract and acts on a positive feedback loop.
Afterbirth
When contractions continue for a time after birth to expel the placenta.
Amniotic sac
This acts as a shock absorber for the baby in the womb.
HCG
This hormone prevents the degeneration of the corpus luteum.
Endometrium
The lining of the uterus into which the placenta grows.
Stimulus
A change in the environment, either internal or external, that is detected by a receptor and elicits a response.
Response
A change in an organism produced by a stimulus.
Reflex
A rapid, unconscious response to a stimulus.
Mechanoreceptors
Hair cells in the cochlea of the ear or pressure receptor cells in the skin.
Chemoreceptors
Receptor cells in the tongue or nerve endings in the nose.
Thermoreceptors
Nerve endings in the skin to detect warm or cold.
Photoreceptors
Rod and cone cells in the eye.
Passage of sound
Eardrum, bones of the middle ear, oval window, hair cells in the cochlea.
Processing of visual stimuli
Convergence, edge enhancement, contralateral processing.
Convergence
Bipolar cells in the retina combine the impulses from groups of rod or cone cells and pass them on to ganglion cells.
Contralateral processing
When the left and right optic nerves meet at a structure called the optic chiasma.
Excitatory synapses
Neurotransmitter released by the presynaptic neuron causes depolarization and an action potential in the postsynaptic neuron. Postsynaptic transmission is therefore excited.
Inhibitory synapses
Neurotransmitter released by presynaptic neuron makes postsynaptic neuron hyper polarized therefore transmission is inhibited.
Excitatory drugs
Nicotine, cocaine, amphetamines
Inhibitory drugs
Bezodiazepines, alcohol, THC
Reasons for addiction to psychoactive drugs
Dopamine secretion, genetic predisposition, social factors.
Medulla oblongata
Controls automatic and homeostatic activities such as digestion, breathing and heart activity
Cerebellum
Coordinates unconscious functions such as balance and movements.
Hypothalamus
Maintains homeostasis, produces hormones and sends releasing factors to stimulate secretion by the pituitary gland
Pituitary gland
Posterior lobe stores and secretes hormones produced by the hypothalamus; anterior lobe produces and secretes hormones that regulate many bodily functions.
Cerebrum
Receives impulses from eye, ear, nose and tongue; acts as integrating center fornhigher complex functions.
Autonomic nervous system
The part of the nervous system that is used to control internal processes unconsciously.
Sympathetic nervous system
Fight, flight and fright nervous system.
Parasympathetic nervous system
Restores body to regular functioning order
Foraging
When animals search for food.
Altruism
Actions that increase another individuals lifetime number of offspring at a cost to ones own survival and reproduction.
Hormones
Chemical messengers, secreted by endocrine glands directly into the blood.
ADH
This hormone causes a reduction in the concentration of the blood plasma by stimulating the kidney to produce hypertonic urine.
Acinus
One group of secretory cells, clustered around the end of a duct.
Content of saliva
Salivary amylase, mucous
Gastric juice
Pepsinogen, hydrochloric acid, muscous
Pancreatic juice
Pancreatic amylase, pancreatic lipase, phospholipase, trypsinogen, carboxypeptidase, alkaline fluid
Pepsinogen
Inactive form of pepsin, activated by hydrochloric acid.
Trypsinogen
Inactive form of trypsin, activated by enterokinase
Helicobacter pylori
An acid-tolerant bacterium that infects the lining of the stomach.
Bile
This is secreted by the liver and stored in the gallbladder.
Emulsification
The breakdown if fats into smaller pieces aided by bile.
Ileum
Digested foods are mainly absorbed in this part of the small intestine.
Microvilli
Protrusions of the free surface of the plasma membrane into the lumen of the ileum
Pinocytic vesicles
Small vesicles, especially near the microvilli.
Liver
Largest organ in the human abdomen.
Hepatic portal vein and hepatic artery
The liver is supplied with blood by these two vessels.
Sinusoids
Vessels that the hepatic portal vein has divided up into.
Roles of the liver
Nutrient storage and regulation, breakdown of erythrocytes, synthesis of plasma proteins, synthesis of cholesterol, detoxification.
Systole
Contraction of the chambers of the heart.
Diastole
Relaxation of the chambers of the heart.
Artherosclerosis
Degenerative disease of large and medium sized arteries.
Thrombosis
The formation of clots
Partial pressure
Pressures exerted by each of the gases in a mixture of gases.
Bohr shift
The release of oxygen by hemoglobin in respiring tissues is promoted by this effect.
Chloride shift
When a carrier protein is used that simultaneously moves a chloride ion into the red blood cell, therefore preventing the balance of charges across the membrane to be altered.
Carbaminohemoglobin
In repairing tissues, carbon dioxide binds reversibly to hemoglobin to form this.
Chemosensors
Cells in the walls of arteries which monitor blood pH and concentrations of oxygen and carbon dioxide in the blood.
7.4
Normal pH of blood.
Clot
Fibrin + red blood cells
Clotting factors
Platelets and damaged cells release these.
Thrombin
This is activated by clotting factors. Inactive form is prothrombin.
Fibrin
This is activated by thrombin. Inactive form fibrinogen.
Fibrinogen
Fibrins inactive form.
Prothrombin
Thrombins inactive form.
Clotting mechanism
Clotting factors, prothrombin, thrombin, fibrinogen, fibrin, fibrin + red blood cells to give clot.
Epitopes
These molecules found on the outside on antigens are recognized by leukocytes and triggers an immune response.
B- cells
The lymph nodes carry a large variety of these lymphocytes.
T-killer cells
Also know as cytotoxic cells.
Natural immunity
Immunity due to infection.
Artificial immunity
Immunity due to inoculation with vaccines.