Cell Biology & Microbiology

Question 1

actin filament

Answer 1

a chain of globular actin molecules that is a major component of the cytoskeleton of eukaryotic cells; abundant in muscle cells

Question 2

ATP (adenosine tri-phosphate)

Answer 2

a high energy phosphate molecule that provides energy for cellular function

Question 3

Calvin Cycle

Answer 3

a series of biochemical, enzyme-mediated, light-dependent reactions that take place in the stroma of chloroplasts of photosynthetic organisms, in which carbon dioxide is reduced into organic molecules; also known as Calvin-Benson Cycle or Carbon Fixation

Question 4

cytochrome

Answer 4

protein found in mitochondrial membranes that functions in oxidative phosphorylation of ADP to form ATP

Question 5

cytoplasm

Answer 5

the contents outside the nucleus of a membrane-bound cell

Question 6

cytoskeleton

Answer 6

a cellular organelle within the cytoplasm that functions to maintain cell shape, enable cell motion, and assist in intra-cellular transport and cellular division

Question 7

diffusion

Answer 7

random continuous movement of particles resulting in an eventually equally

Question 8

electron transport chain

Answer 8

mitochondrial enzymes that transfer electrons from one complex (I, II, III, and IV) to another, resulting in ATP formation; also known as the respiratory chain

Question 9

endocytosis

Answer 9

process of material uptake into a cell without passing through the cell membrane

Question 10

endoplasmic reticulum (ER)

Answer 10

network of membranes within a cell’s cytoplasm that is involved in the synthesis, modification, and transport of cellular materials

Question 11

exocytosis

Answer 11

a process of cellular secretion through vesicle transport to the cell surface, where the vesicle fuses with the plasma membrane

Question 12

facilitated diffusion

Answer 12

a passive process of transporting ions or molecules by a specific carrier protein in a membrane

Question 13

gap junctions

Answer 13

protein channel intercellular network that facilitates passage of ions, hormones, and neurotransmitters from cell to cell

Question 14

glycolysis

Answer 14

the initial metabolic pathway, completely anaerobic, of carbohydrate catabolism; the most universal process (but not the most efficient) by which all types of cells derive energy from sugars

Question 15

Golgi apparatus

Answer 15

stack of membranous vesicles that functions in secretion formation within a cell; present in most living cells

Question 16

hydroplasm

Answer 16

the liquid contents of the gastro-vascular tube

Question 17

internal membrane

Answer 17

membrane that surrounds organelles; present only in eukaryotic cells

Question 18

interphase

Answer 18

the non-divisional stage of the cell cycle, during which the DNA is replicated in the nucleus

Question 19

Krebs cycle

Answer 19

a series of chemical reactions in aerobic respiration occurring naturally in animals; also known as the citric acid cycle

Question 20

lysosome

Answer 20

a membrane-bound organelle in a cell’s cytoplasm that functions in intracellular digestions

Question 21

microtubule

Answer 21

long, stiff, hollow cylindrical structure that is a major component of the cytoskeleton and functions to regulate eukaryotic cell’s shape and to control movement

Question 22

mitochondria

Answer 22

a specialized structure located within cells that metabolize particles into energy sources

Question 23

nuclear envelope

Answer 23

the membrane system surrounding the nucleus of eukaryotic cells; the system consists of inner and outer membranes that are separated by perinuclear space and perforated by nuclear pores

Question 24

nucleus

Answer 24

the cell part containing DNA and RNA; responsible for growth and reproduction; the positively-charged, dense center of an atom

Question 25

organelle

Answer 25

differentiated structure (e.g., mitochondrion, vacuole, or chloroplast) within a cell that performs a specific function

Question 26

oxidative phosphorylation

Answer 26

the formation of ATP from ADP, taking place in the electron transport chain of the mitochondrion

Question 27

passive transport

Answer 27

substance transport across a cell membrane by diffusion that does not require energy expenditure

Question 28

permease

Answer 28

a cell-membrane transport protein or carrier molecule that functions as a transport channel across cellular membranes

Question 29

peroxisome

Answer 29

eukaryotic organelle that has a single membrane separating it from a cell’s internal fluid (cytosol)

Question 30

phagocytosis

Answer 30

the process in which a cell engulfs and digests or destroys particulate material

Question 31

phosphorylation

Answer 31

the process of adding phosphate groups to a compound

Question 32

plasma membrane

Answer 32

the boundary membrane of a cell, which serves as a selective barrier to regulate the cell’s chemical composition

Question 33

pore

Answer 33

a minute opening in tissue that serves as an outlet for perspiration (animals) or as a means of absorption and transpiration (plants)

Question 34

protoplasm

Answer 34

a cell’s living substance, including the cytoplasm and nucleus

Question 35

protozoan

Answer 35

an animal-like, single-celled eukaryotic organism of economic and scientific importance; many are parasitic, commensal, and/or free-living; responsible for a number of diseases

Question 36

respiration

Answer 36

the metabolic process that takes place in cells and tissues with the release of energy, the production of carbon dioxide, and the absorption of blood for transport to the lungs

Question 37

ribosome

Answer 37

a complex cell organelle constructed in the nucleolus, functioning as the site of protein synthesis in the cytoplasm that is composed of proteins plus rRNA and that catalyzes translation of messenger RNA into an amino acid sequence Ribosomes are made up of two non-identical subunits each consisting of a different rRNA and a different set of proteins

Question 38

rough endoplasmic reticulum (RER)

Answer 38

a membranous tube and sac system of the endoplasmic reticulum that functions in the manufacture of membrane-bound proteins

Question 39

selectively permeable

Answer 39

a membrane that permits certain materials to cross

Question 40

smooth endoplasmic reticulum

Answer 40

a membranous tubes system of the endoplasmic reticulum that functions in lipid synthesis

Question 41

vesicle

Answer 41

a small bladder-like cell that contains fluid