Biology Definitions. Flashcards
ADH
Anti-diuretic hormone is released to signal to the kidneys to reabsorb water – in times of dehydration or low water in body
Diuretic.
To produce urine.
Dilation.
To open wider.
Kleptothermy
To huddle for warmth.
Constrict
To narrow.
Vector.
An organism that spreads a disease from one organism to another – but does not suffer from the disease
Metabolic.
Chemical reactions that produce heat or energy
Physiological
An internal function of a system or organ
Pathogen
Something that causes disease or damage
Antibody
Proteins that are made by the immune system (B cells) to bind to pathogens and disable their pathogenic effect on the tissues or cells.
Correlation
How a variable effects another variable – often seen in data displays, variables are usually found on the graph axes
Antigen
Is a molecular marker on a pathogen or foreign particle, it causes a specific immune response as an antibody will bind to it to disable the pathogen.
B cell
B cells are a type of white blood cell that makes infection-fighting proteins called antibodies.
T cell
T cells are a type of white blood cell called lymphocytes. They help your immune system fight germs and protect you from disease.
Behavioural
A physical movement of an organism in response to the environment eg. To seek shade on a hot day.
Action potential
Occurs when a neuron sends information down the axon – away from the cell body. It is like a pulse of electrical energy moving down the axon.
Mesophyte
Plant with many stomata, thin soft non-waxy leaves, these are adapted to moderate environments.
Halophyte
Plant adapted to salty soil or conditions, adaptations include storing salt in the roots, extensive roots to increase potential water uptake, fewer and small stomata to reduce water loss.
Hydrophyte
Plant adapted to living in water. These plants have thin leaves with air spaces in them for buoyancy, stomata on the upper surface, thin soft leaves with no waxy cuticle.
Stomata.
Stomata are tiny openings or pores that enable gaseous exchange. Stomata are usually found in plant leaves, but they can also be found in some stems.
Xerophyte
Plant that is adapted to dry hot conditions. Thick waxy cuticles, hard small leaves, few stomata, they can sometimes store water, have extensive root systems for uptake of water.
Cuticle
The ‘skin’ of the leaf. This can be waxy to protect it from heat and water loss, or it can be soft when in aquatic or moderate environments.
Immune Serum
Immune serum is a protein that is found in the plasma (in blood), it is contains antibodies and is used to provide passive immunity for a variety of diseases (hep A, measles).
Booster
A vaccine to complement an initial or first vaccine. A booster is given after an initial vaccine to improve immunity.
Antibiotic
A medication that combats bacteria.
Permeability
The ability for a membrane to let substances through it (like a sieve).
Vacuole
A storage vesicle inside a cell – in plant cells these store water.
Synapse
The space in between the axon terminal of one neuron, and the dendrites of the neighboring neuron.
Dendrite
The branch like endings that receive information from neighbouring neurons’ axon terminals.
Axon
The long section between the neuron cell body and the axon terminals. It is made of Schwann cells and has an insulated myelin sheath so the electrical impulses (action potential) that travels down the axon is not interrupted.
Myelin sheath
an insulated outer layer of fats, so the electrical impulses (action potential) that travels down the axon is not interrupted.
Natural immunity
Immunity brought about naturally – can be passive (breastfeeding) or active (catching a cold). But both will increase immunity.
Artificial immunity
Immunity brought about artificially – can be passive (blood serum treatment) or active (vaccination). Both increase immunity.
MHC
Major Histocompatibility Complex, this is a special marker on the outside of a cell that helps the immune system recognize foreign substances (eg. A macrophage engulfs a bacteria, it partially digests it and then displays a marker on the outside to attract a T cell to come and destroy the pathogen), or to indicate that it is an uninfected healthy cell.
Homeostasis
The maintenance of any system – it is controlled through negative feedback, where any change is reversed to bring the system back to balance.
Effector
The control centre that receives and then processes information from a receptor. The effector will bring about an effect! Either reversing the change, or enhancing it.
Receptor
A receptor is a sensor – it detects a change in the internal or external environment. Eg. Chemoreceptors detect changes in pH of blood.
Phagocytic
The process of engulfing a particle and digesting it – can be a free-living single cell like an amoeba, or in the human body it can be a white blood cell (macrophage)
Prostaglandin
A group of fats that are made at sites of tissue damage/resemblance of injury, they mediate the inflammatory process. They are pro-inflammatory.
histamine
A molecule that is pro-inflammatory. It promotes or enhances blood vessel changes (permeability/leaky and dilation/opening) and tissue changes (increased temp and fluids arriving at tissue effected), it can attract other molecules like phagocytic cells.
