Biology Honors Cell Unit Test Vocabulary

Front 1

cell membrane

Back 1

the lipid bilayer that forms the outer boundary of a cell

Front 2

cell wall

Back 2

the rigid structure that surrounds the cells of plants, fungi, many protists, and most bacteria

Front 3

cytoplasm

Back 3

the region of a cell between the cell membrane and the nucleus.

Front 4

flagellum

Back 4

a hairlike structure made up of microtubules that function in locomotion

Front 5

mitochondria

Back 5

the organelle that is the sight of aerobic respiriation in eukaryotic cells

Front 6

nuclear envelope

Back 6

a double membrane that surrounds the nucleus of a eukaryotic cell

Front 7

diffusion

Back 7

the process by which molecules move from an area of greater concentration to an area of lesser concentration

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hypertonic

Back 8

describing a solution whose solute concentration is higher than that inside a cell

Front 9

passive transport

Back 9

the movement of substances across a cell membrane without the use of cell energy

Front 10

vesicle

Back 10

a membrane bound sac in a eukaryotic cell that contains materials involved in endocytosis, exocytosis, or transport within a cell

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cytolysis

Back 11

the bursting of a cell

Front 12

chlorophyll

Back 12

a class of light absorbing pigments used in photosynthesis

Front 13

light reactions

Back 13

the initial reactions in photosynthesis, including the absorbtion of light by photosystems I and II, the passage of electrons along the electron transport chains, the production of NADPH and O2 , and the synthesis of ATP through chemiosis.

Front 14

stroma

Back 14

in plants, the solution that surrounds the thylakiods in a chloroplast

Front 15

alcoholic fermentation

Back 15

the process by which pyruvic acid is converted to ethyl alcohol; the anaerobic action of yeast on sugars

Front 16

lactic acid fermentation

Back 16

the process by which pyruvic acid is converted to lactic acid.

Front 17

Krebs cycle

Back 17

a series of biochemical reactions that release carbon dioxide and result in the formation of ATP

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centromere

Back 18

a region of the chromosome where the two sister chromatids are held together and which is the site of attachment of the chromosome to the spindle fibers during mitosis

Front 19

anaphase

Back 19

a phase of mitosis and meiosis in which the chromosomes separate

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centriole

Back 20

a structure that appears during mitosis in animal cells

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interphase

Back 21

a period of cell growth and development that preceeds eukaryotic cell nuclear division

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prophase

Back 22

the first stage of mitosis and meiosis, characterized by the condensation of chromosomes

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nucleus

Back 23

the organelle that contains most of the DNA and directs most of the cells activites

Front 24

chloroplast

Back 24

a plastid containing chlorophyll; the site of photosynthesis

Front 25

cytosol

Back 25

the gelatinlike aqueous fluid that bathes the organelles on the inside of the cell membrane

Front 26

golgi apparatus

Back 26

a system of membranes in eukaryotic cells that modifies protiens for export by the cell

Front 27

nucleolus

Back 27

the structure in which ribosomes are synthesized and partially assembled; found in most nuclei

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nuclear pore

Back 28

a small hole in the nuclear envelope through which substances pass between the nucleus and the cytoplasm

Front 29

equilibrium

Back 29

a state that exists when the concentration of a substance is the same throughout a space

Front 30

hypotonic

Back 30

describing a solution whose solute concentration is lower than that inside a cell

Front 31

active transport

Back 31

the movement of a substance across a cell membrane against a concentration gradient; requires the cell to expend energy

Front 32

carrier protien

Back 32

a protein that transports specific substances across a biological membrane

Front 33

plasmolysis

Back 33

the wilting or shrinking of a walled cell in a hypertonic environment

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electron transport chain

Back 34

molecules in the thylakoid membrane or inner mitochondrial membrane that uses some of the energy in the electrons to pump protons across the membrane

Front 35

photosynthesis

Back 35

the conversion of light energy into chemical energy stored in organic compounds

Front 36

thylakoid

Back 36

a flattened, membraneous sac inside a chloroplast; contains most of the components involved in the light reactions of photosynthesis

Front 37

cellular respiration

Back 37

the process in which cells make ATP by breaking down organic compounds

Front 38

pyruvic acid

Back 38

a three carbon molecule that is the end product of glycolysis

Front 39

cristae

Back 39

a fold of the inner membrane of a mitochondria

Front 40

chromatid

Back 40

one of two identical parts of a chromosome

Front 41

cell cycle

Back 41

the events of cell division; includes interphase, mitosis, and cytokinesis

Front 42

cleavage furrow

Back 42

the area of the cell membrane that pinches in and eventually separates the dividing cells

Front 43

metaphase

Back 43

the second phase of mitosis; during which all the chromosomes move to the cells equator

Front 44

telophase

Back 44

the final stage of mitosis during which a nuclear membrane forms around each new set of chromosomes

Front 45

prokaryote

Back 45

a unicellular organism that lacks a nucleus and membrane bound organelles

Front 46

chromosome

Back 46

DNA and protien in a coiled, rod shaped form that occurs during cell division

Front 47

endoplasmic reticulum

Back 47

a system of membraneous tubules and sacs in eukaryotic cells that functions as a path along which molecules move from one part of the cell to another

Front 48

lysosome

Back 48

an organelle containing digestive enzyme, existing primarily in animal cells

Front 49

ribosome

Back 49

an organelle that functions in the synthesis of protiens

Front 50

facilitated diffusion

Back 50

a process in which substances move down their concentration gradient across the cell membrane with the assistance of carrier protiens

Front 51

isotonic

Back 51

describing a solution whose solute concentration equals that inside a cell

Front 52

endocytosis

Back 52

the process by which a cell surrounds and engulfs substances

Front 53

turgor pressure

Back 53

water pressure within a plant cell

Front 54

histone

Back 54

a protien molecule that DNA wraps around during chromosome formation

Front 55

cytokinesis

Back 55

the division of the cytoplasm of one cell into two new cells.

Front 56

mitosis

Back 56

eukaryotic nuclear division

Front 57

eukaryote

Back 57

a cell that contains a nucleus and membrane bound organelles

Front 58

cilia

Back 58

short, hairlike organelles that extend from a cell and functions in locomotion or in the movement of substances across a cell surface

Front 59

microtubule

Back 59

a hollow tube of protein that constitutes the largest strand in the cytoskeleton

Front 60

vacuole

Back 60

a fluid filled organelle that stores enzymes or metabolic wastes in a plant cell

Front 61

osmosis

Back 61

the diffusion of water across a selectively permeable membrane

Front 62

exocytosis

Back 62

a process in which a vesicle inside a cell fuses with the cell membrane and releases its contents to the external environment

Front 63

granum

Back 63

a stack of thylakoids in a chloroplast

Front 64

photosystem

Back 64

in plants, a unit of several hundred clorophyll molecules and carotenoid pigment molecules in the thylakoid membrane

Front 65

Calvin cycle

Back 65

a biochemical pathway of photosynthesis in which CO2 is converted into carbohydrate

Front 66

glycolysis

Back 66

a pathway in which glucose is oxidized to pyruvic acid

Front 67

chemiosmosis

Back 67

a process in chloroplasts an mitochondria in which the movement of protons down thier concentration gradient across a membrane is coupled to the synthesis of ATP

Front 68

mitochondrial matrix

Back 68

the space inside the inner membrane of a mitochondrion