Module 6 definitions

Question 1

Define “digestion”.

Answer 1

The breakdown of absorbed substances.

Question 2

Define “respiration”.

Answer 2

The breakdown of food molecules with a release of energy.

Question 3

Define “excretion”.

Answer 3

The removal of soluble waste materials.

Question 4

Define “egestion”.

Answer 4

The removal of nonsoluble waste materials.

Question 5

Define “secretion”.

Answer 5

The release of biosynthesized substances.

Question 6

Define “homeostasis”.

Answer 6

Maintaining the status quo.

Question 7

Define “reproduction”.

Answer 7

Producing more cells.

Question 8

Define “absorption”.

Answer 8

The transport of dissolved substances into cells.

Question 9

Define “cytology”.

Answer 9

The study of cells.

Question 10

Define “cell wall”.

Answer 10

A rigid structure on the outside of certain cells, usually plant and bacteria cells.

Question 11

Define “middle lamella”.

Answer 11

The thin film between the cell walls of adjacent plant cells.

Question 12

Define “plasma membrane”.

Answer 12

The semipermeable membrane between the cell contents and either the cell wall or the cell’s surroundings.

Question 13

Define “cytoplasm”.

Answer 13

A jellylike fluid inside the cell in which the organelles are suspended.

Question 14

Define “ions”.

Answer 14

Substances in which at least one atom has an imbalance of protons and electrons.

Question 15

Define “cytoplasmic streaming”.

Answer 15

The motion of cytoplasm in a cell that results in a coordinated movement of the cell’s contents.

Question 16

Define “mitochondria”.

Answer 16

The organelles in which nutrients are converted to energy.

Question 17

Define “lysosome”.

Answer 17

The organelle in animal cells responsible for hydrolysis reactions that break down proteins, polysaccharides, disaccharides, and some lipids.

Question 18

Define “ribosomes”.

Answer 18

Non- membrane-bounded organelles responsible for protein synthesis.

Question 19

Define “endoplasmic reticulum”.

Answer 19

An organelle composed of an extensive network of folded membranes that performs several tasks within a cell.

Question 20

Define “rough ER”.

Answer 20

ER that is dotted with ribosomes.

Question 21

Define “smooth ER”.

Answer 21

ER that has no ribosomes.

Question 22

Define “leucoplasts”.

Answer 22

Organelles that store starches or oils.

Question 23

Define “chromoplasts”.

Answer 23

Organelles that contain pigments used in photosynthesis.

Question 24

Define “central vacuole”.

Answer 24

A large vacuole that rests at the centre of most plant cells and is filled with a solution that contains a high concentration of solutes.

Question 25

Define "waste vacuoles".

Answer 25

Vacuoles that contain the waste products of digestion.

Question 26

Define "phagocytosis".

Answer 26

The process by which a cell engulfs foreign substances or other cells.

Question 27

Define "phagocytic vacuole".

Answer 27

A vacuole that holds the matter which a cell engulfs.

Question 28

Define "pinocytic vesicle".

Answer 28

A vesicle formed at the plasma membrane to allow the absorption of large molecules.

Question 29

Define "secretion vesicle".

Answer 29

A vesicle that holds secretion products so that they can be transported to the plasma membrane and released.

Question 30

Define "golgi bodies".

Answer 30

The organelles where proteins and lipids are stored and then modified to suit the needs of the cell.

Question 31

Define "microtubules".

Answer 31

Spiral strands of protein molecules that form a tubelike structure.

Question 32

Define "nuclear membrane".

Answer 32

A highly porous membrane that separates the nucleus from the cytoplasm.

Question 33

Define "chromatin".

Answer 33

Clusters of DNA, RNA, and proteins in the nucleus of a cell.

Question 34

Define "cytoskeleton".

Answer 34

A network of fibres that holds the cell together, helps it keep its shape, and aids in movement.

Question 35

Define "microfilaments".

Answer 35

Fine, threadlike proteins found in the cell's cytoskeleton.

Question 36

Define "Intermediate filaments".

Answer 36

Threadlike proteins in the cell's cytoskeleton that are roughly twice as thick as microfilaments.

Question 37

Define "phospholipid".

Answer 37

A lipid in which one of the fatty acid molecules has been replaced by a molecule that contains a phosphate group.

Question 38

Define "passive transport".

Answer 38

Movement of molecules through the plasma membrane according to the dictates of osmosis or diffusion.

Question 39

Define "active transport".

Answer 39

Movement of molecules through the plasma membrane (typically opposite the dictates of osmosis or diffusion) aided by a process that requires energy.

Question 40

Define "isotonic solution".

Answer 40

A solution in which the concentration of solutes is essentially equal to that of a cell which resides in the solution.

Question 41

Define "hypertonic solution".

Answer 41

A solution in which the concentration of solutes is greater than that of a cell that resides in the solution.

Question 42

Define "plasmolysis".

Answer 42

Collapse of a walled cell's cytoplasm due to a lack of water.

Question 43

Define "cytolysis".

Answer 43

The rupturing of a cell due to excess internal pressure.

Question 44

Define "hypotonic solution".

Answer 44

A solution in which the concentration of solutes is less than that of a cell that resides in the solution.

Question 45

Define "activation energy".

Answer 45

Energy necessary to get a chemical reaction going.