AP Bio homework quiz #1- animal form and function

is it accurate to define homeostasis as a constant internal environment

No, an animals internal environment fluctuates within a normal range or around set points

great diversity of B and T cells produced

V and J gene segments of light and heavy chain allele

dendtric cells

WBC located in the skin that move to lymph nodes and stimulate adaptive immunity

eosinophils

WBC that attack parasitic worms with enzymes

natural killer cells

WBC that attack the bodes infected or cancerous cells

clonal selection

antigen receptor binds to antigen, then the selected cell divides into a clone of effector cells and memory cells specific for that antigen

what substances remain in the capillaries

blood cells, large molecules such as plasma proteins

histamine

causes vasodilation and increased permeability of blood vessels

immunological memory

enhanced response to previously encountered foreign molecule

lysozyme

enzyme that attacks bacterial cell walls, found in tears, saliva mucus

function of filtration step in excretory systems

filtration produces a fluid for exchange process that is free of cells and large molecules, benefits the animal because otherwise they could not be readily absorbed

if a child were born without a thymus what cells and functions would they be deficient in

have no functional T cells, unable to produce antibodies against extracellular bacteria, childs immune system would be unable to kill viruses

endocrine system

hormones are released and travel more slowly, signals last longer, mediate responses, coordinates gradual function

what advantage does uric acid offer was a nitrogenous waste in arid environments

insoluble in water, excreted as a semi solid paste, reduces animals water loss

macrophages

large phagocytes that engulf microbes

explain to advantages of having memory cells when a pathogen is encountered for a second time

memory cells ensure that both a receptor specific for a particular epitope will be present and there will be more lymphocytes in the host than as encountered before by the pathogen

nervous system

nerve impulses are faster and travel quicker, shorter responses, regulates rapid response (behavior)

neutrophils

phagocytic white blood cells

interferons

proteins released by by virus-infected cells that stimulate neighboring cells to produce substances that inhibit viral replication

mast cells

release histamine to initiate inflammatory response

cytokines

set of blood proteins that cause lysis of microbes and are involved with innate and adaptive defenses

complement system

signaling proteins that enhance an immune response and promote blood flow to injury response

positive feedback

stimulus is reinforced (childbirth)

what prevents B and T cells from reacting against the bodys own molecules

tested for self reactivity, if its wrong, they will self destruct

negative feedback

try to get body back to original state (throwing up)

what substances are removed from blood during filtration

water, salts, nitrogenous wastes, glucose, vitamins, other small molecules