27 terms

Biology test 1 flashcards

group of organisms that can interbreed and produce fertile offspring
testable explanation of a situation
control group
group not being tested
experimental group
group being tested or affected
quantitative or qualitative information gained from scientific investigation
accept, reject, suspend hypothesis
all of the chemical reactions that occur within an organism
regulations of an organism's internal conditions to maintain life
any inherited characteristics that results from change to a species over time
hereditary changes in groups of living organisms over time
compound light microscope
microscope that consists of a series of glass lenses and uses visible light to produce a magnified image.
electron microscopes
microscope that uses magnets to aim a beam of electrons at thin slices of cells
transmissive electron microscopes
can magnify up to 500,000X, but the specimen must be dead, sliced very thinly, and stained with heavy metal
scanning electron microscope
directs electrons over the surface of the specimen, producing a 3D image
the basic structural and functional unit of all organisms
specialized internal cell structure that carries out specific cell functions such as protein synthesis and energy transformation
The Cell Theory
states that organisms are made of one or more cells; cells are the basic unit of life; and all cells come only from other cells
prokaryotic cells
microscopic, unicellular organisms without a nucleus or other membrane-bound organelles
eukaryotic cells
unicellular organism with membrane-bound nucleus and organelles; generally larger and more complex than a prokaryotic cell
Plasma membrane
is a special boundary that helps control what enters and leaves the cell.
Selective Permeability
by which a membrane allows some substances to pass through while keeping others out
regulation of an organism's internal environment to maintain conditions needed for life
Phospholipid Bilayer
plasma membrane layers composed of phospholipid molecules arranged with polar heads facing the outside and non polar tails facing the inside
molecule that has a glycerol backbone, two fatty acid chains, and a phosphate-containing group
Phosphate Head
the polar head of a phospholipid that is attracted to water, because water is also polar
Fatty Acid Tail
non polar tails of a phospholipid that are repelled by water
carbohydrate chain
carbohydrates attached to proteins, that stick out from the plasma membrane to define the cells characteristics and help cells identify chemical signals