BiologyUnit2VocabFlashcards
atp
adenosine triphosphate; a compound that has three phosphate groups and is used by cells to store energy and to fuel many metabolic processes
adp
adenosine diphosphate; the compound that remains when a phosphate group is removed from ATP, releasing energy
oxidation
loss of electrons
reduction
gain of electrons
digestion
the organic process by which food is converted into substances that can be absorbed by the body
extracellular digestion
the breakdown of nutrient molecules outside of cells
intracellular digestion
the breakdown of nutrients within a cell
saliva
liquid secreted in the mouth; begins mechanical and chemical digestion
peristalsis
the rhythmic waves of contraction of the smooth muscle that pushes food through the digestive tract
salivary amylase
an enzyme in saliva that begins digestion of starch into disaccharides
gastrin
a digestive hormone secreted by the stomach lining; stimulates the secretion of fluid by gastric glands in the stomach
pepsin
a protein-splitting enzyme secreted by the gastric glands of the stomach
trypsin
an enzyme in the pancreatic juice that breaks down protein molecules
bile
a secretion of the liver stored in the gallbladder and released through a duct in the small intestine; breaks large fat droplets into smaller ones that enzymes can act on more efficiently
lipase
a fat-digesting enzyme
villi
a fingerlike projection of the small intestine that increases surface area for absorption of digested food
capillaries
microscopic blood vessels penetrating the tissues and consisting of a single layer of cells that allows exchange between the blood and tissue fluids
symbiosis
a close connection between two different living creatures from which both usually get benefits
mutualism
the relation between two different species of organisms that are interdependent; each benefits from the other
carrying capacity
the maximum number of individuals that a given environment can support without detrimental effects
limiting factor
an environmental factor that tends to limit population size
homeostasis
the ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes
nervous system
the sensory and control apparatus consisting of a network of nerve cells
integumentary system
the skin and its appendages
endocrine system
the system of glands that produce endocrine secretions that help to control bodily metabolic activity
organelle
a specialized part of a cell
organism
a living thing that has (or can develop) the ability to act or function independently
organ
a fully differentiated structural and functional unit in an animal that is specialized for some particular function
organ system
a group of organs that work together to preform a common task
population
a group of organisms of the same species populating a given area
community
a group of interdependent organisms inhabiting the same region and interacting with each other
ecosystem
a system formed by the interaction of a community of organisms with their physical environment
biome
a major biotic community characterized by the dominant forms of plant life and the prevailing climate
biosphere
the regions of the surface and atmosphere of the Earth (or other planet) where living organisms exist
