Chapter 12: Animal Systems and Homeostasis Flashcards Preview

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Flashcards in Chapter 12: Animal Systems and Homeostasis Deck (81):
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homeostasis

the physiological condition in which the body maintains stable internal conditions

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countercurrent exchange

the opposite flow of adjacent fluid that maximizes heat transfer, or transfer rates between fluids

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set point

the optimal value of a physiological variable

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positive feedback

a homeostatic response to a stimulus in which the effector exaggerates the stimulus

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negative feedback

a homeostatic response to a stimulus in which the effector removes the stimulus

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endotherms

organisms that use internal energy to maintain a constant body temperature (ex: mammals and birds)

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ectotherms

organisms that use external energy or behavior to maintain body temperature (ex: reptiles or invertebrates)

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histology

the microscopic structure of plant and animal tissues, and the branch of biology that studies this

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matrix

an embedding material

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collagen

common protein present in connective tissues

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phagocytosis

the process in which a cell engulfs extracellular particles by surrounding them with extensions of the plasma membrane

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lacuna

a gap or cavity

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Haversian system

a unit of bone consisting of concentric layers of bone, a central Haversian canal with a blood vessel, and a system of microscopic interconnecting canals

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sphincter

a circular muscle that surrounds an opening and regulates entry and exit

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peristalsis

the rhythmic, involuntary contraction of the digestive tract

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neuron

a cell type in nervous tissue that is specialized to initiate and transmit nerve impulses

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neuroglia

a group of cells associated with neurons that perform various support functions (hint: "neuron glue")

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zymogen

inactive form of a digestive enzyme

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villi

the finger-like projections lining the small intestine fundamental to absorption

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lacteal

a small vessel of the lymphatic system that transports lymph

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chylomicrons

small globules (formed in the epithelial cells of the small intestine) composed of fats mixed with cholesterol and coated with special proteins

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enterogastrones

hormones secreted by the wall of the duodenum

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egestion

getting rid of left over, undigested materials

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excretion

getting rid of a metabolic product, such as CO2

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mutualistic symbiont

the smaller participant in a relationship that benefits both organisms

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cnidaria

a phylum of radially symmetrical organisms including the jellyfish, anemones, and corals

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polychaetes

a member of a class of mostly marine worms (Polychaeta) in the phylum Annelida

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negative pressure breathing

a ventilation system that works like a suction pump that pulls air into the lungs

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diaphragm

the sheet of visceral muscle that separates the thoracic cavity from the abdominal cavity

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myoglobin

an oxygen-storing protein similar to hemoglobin that is exclusively found in muscles

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buffer

a substance that minimizes changes in pH by adding or removing H+ from the solution

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EKG

output from a medical procedure which measures electrical impulses in the heart

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endothelium

inner lining of tightly packed cell

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sphygmomanometer

instrument used to measure blood pressure

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collagen

the most abundant protein in the body. It forms strong fibers involved in the clotting process.

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metabolism

the sum of all catabolic (breakdown) and anabolic (synthesis) reactions in the body

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urea

nitrogenous waste that is metabolized by bacteria and forms ammonia

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deamination

the removal of an amino group from a molecule

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renal

of or pertaining to the kidneys

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nephron

the functional unit of the kidney consisting of a long tubule and associated capillaries

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interstitial fluid

the fluid filling the space between cells in vertebrate

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pus

a fluid containing dead white blood cells

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leukocyte

white blood cell

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erythrocyte

red blood cell

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antigen

any chemical that is foreign to an organism and that causes an immune response; an antibody generator

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effector cells

lymphocytes that do not further differentiate

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clonal selection theory

the scientific theory in immunology that explains the functions of cells (lymphocytes) of the immune system in response to specific antigens invading the body

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CD4

a cell-surface protein found on helper T cells that enhances the interaction between an antigen presenting cell (macrophage) and the helper T cell

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interleukin I

a protein secreted by antigen-presenting macrophages that activates the helper T

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cytokines

proteins or peptides that stimulate other lymphocytes

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vaccine

a harmless variant of a pathogen that stimulates an immune response against the actual pathogen

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introns

non-coding sequences found within genes

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mesentery

a large, tangled mass of blood vessels in the small intestine, which allow food to be absorbed into the bloodstream and feul the body

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signal transduction pathways

mechanisms that link a chemical or mechanical stimulus to a cellular response

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tropic hormones

hormones targeted towards other endocrine glands

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menstrual cycle

a reproductive cycle in higher female primates characterized by the shedding of the nonpregnant endometrium

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estrous cycle

a reproductive cycle characterized by the reabsorption of the nonpregnant endometrium

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dendrites

fibrous extensions of a nerve cell that receive input

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myelin sheath

formed from Schwann cells wrapped around an axon

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reflex

inborn, automatic response

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synapse

the space between the dendrite of one neuron and the axon of another neuron

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voltage

a difference in potential

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depolarization

an electrical state that takes place when the inside of a cell is made less negative relative to the outside than at the resting potential

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voltage-gated ion channels

passageways made of protein that allow ions to enter and exit the cell under certain conditions

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threshold potential

the membrane potential (voltage) at which the gates swing open

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endorphin

neurotransmitter that acts as a natural painkiller

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ganglion

an aggregation of nerves external to the brain or spinal cord

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central nervous system (CNS)

a nervous system made up of a brain along with one or two longitudinal nerve cords

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brain

a concentration of ganglia in one location of an animal's body, usually the head

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autonomic

describes a body function that occurs automatically

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neuromuscular junctions

regions where neurons and muscles meet

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T tubules

deep infoldings of the plasma membrane into the interior of a muscle cell

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tropomyosin

a long protein that blocks myosin binding sites on the actin filament

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rhodopsin

the most ubiquitous light-sensing protein in animals

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statolith

"stationary stone"; a structure acquired from the environment (usually a grain of sand) that stimulates mechanoreceptors in the statocyst or other balance organ in some invertebrates

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otoliths

"ear stones"; structures made of calcium carbonate in the vertebrate ear that aid in the detection of movement

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cupula

a gelatinous organ that functions in maintaining balance

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middle ear

the region of the ear between the tympanic membrane and the oval and round windows, containing the malleus, incus, and stapes, the bones that conduct and amplify sound vibrations

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inner ear

the fluid-filled cochlea that conducts sound vibrations and contains the basilar membrane, the basis for pitch discrimination, and the organ of Corti that translate vibration into nerve impulses

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organ of Corti

a structure in the inner ear containing hair cells that translate vibration into action potential in the auditory nerves

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action potential

a rapid change in the membrane potential of an excitable cell