BIOLOGY: LIFE PROCESSES AT THE CELLULAR LEVEL

Question 1

Passive transport

Answer 1

the movement of particles across a plasma (cell) membrane from high to low concentration without using any energy

Question 2

Diffusion

Answer 2

the net movement of particles from high concentration to low concentration

Question 3

Facilitated diffusion

Answer 3

the movement of particles from high concentration to low concentration through a channel protein

Question 4

Osmosis

Answer 4

the movement of water from high to low concentration through a semipermeable membrane

Question 5

Channel proteins

Answer 5

proteins that create ‘pores’ in the cell membrane though which particles (eg Nat) diffuse

Question 6

Carrier proteins

Answer 6

proteins in the cell membrane that change shape when particles (eg amino acids) bind to them, creating a channel for those particles to pass through

Question 7

Flaccid

Answer 7

cells drooping due to a lack of water

Question 8

Turgid

Answer 8

cells are swollen due to the cells containing a large amount of water

Question 9

Plasmolysed

Answer 9

shrinking of the cytoplasm away from the cell wall in plant cells due to water flowing our of the cell by osmosis

Question 10

Exocytosis

Answer 10

the movement of large molecules OUT of cells by the folding of membranes

Question 11

Active transport

Answer 11

the movement of particles across a plasma membrane from low to high concentration using energy (ATP)

Question 12

Cytosis

Answer 12

the movement of large molecules into or out of cells by the folding of membranes

Question 13

Endocytosis

Answer 13

the movement of large molecules INTO cells by the folding of membranes

Question 14

Pinocytosis

Answer 14

a type of cytosis where the cell takes up liquid material

Question 14

Phagocytosis

Answer 14

a type of cytosis where the cell takes up solid material

Question 15

Hypotonic solution

Answer 15

a solution that has a high concentration of water and a low concentration of solute

Question 16

Isotonic

Answer 16

two solutions that have an equal concentration of water and an equal concentration of solute

Question 17

Enzyme

Answer 17

a protein with a specific shape that acts as a biological catalyst

Question 17

Hypertonic solution

Answer 17

a solution that has a low concentration of water and a high concentration of solute

Question 18

Lysis

Answer 18

the destruction of a cell by the rupturing of its cell membrane

Question 19

Active site

Answer 19

the part of the enzyme that binds to a substrate

Question 20

Anabolic enzyme

Answer 20

one that forms larger molecules (eg proteins) from smaller ones (eg amino acids)

Question 20

Activation energy

Answer 20

the minimum amount of energy the reacting species must possess to undergo a specific reaction

Question 21

Catabolic enzyme

Answer 21

one that breaks larger molecules (eg starch) into smaller ones (eg glucose)

Question 22

Denaturing

Answer 22

when the shape of the active site of an enzyme changes so it can no longer bind to the substrate

Question 23

Co-factors

Answer 23

small molecules that bind into the active site of an enzyme and assist enzymes in catalysing a reaction

Question 24

Lock and Key model

Answer 24

enzymes active site have a specific shape to which only one substrate can fit

Question 25

Induced fit model

Answer 25

The active site of an enzyme changes shapes (ie is moulded) to fit a specific substrate

Question 26

Co-enzymes

Answer 26

act as a bridge to lock the enzyme and substrate molecule together more tightly

Question 27

Enzyme competitive inhibitors (poisons)

Answer 27

these are molecules that bind to the active site of an enzyme and prevent the substrate from binding

Question 28

Metabolic pathway

Answer 28

A reaction that occurs over a series of small, enzyme controlled steps to produce an end product eg respiration

Question 28

Enzyme non-competitive inhibitors (poisons)

Answer 28

bind to a part of the enzyme that is NOT the active site but causes the enzymes shape to distort so that the substrate can't bind to 
the enzyme

Question 29

Photosynthesis

Answer 29

the process by which plants make food (glucose)

Question 30

Respiration

Answer 30

the process by which glucose is broken down to release ATP energy

Question 31

Chromatin

Answer 31

a complex of DNA wound around histone proteins

Question 31

Aerobic respiration

Answer 31

respiration with oxygen

Question 32

Anaerobic respiration

Answer 32

respiration without oxygen

Question 33

Chromosome

Answer 33

A single strand of DNA wound around histone proteins that contains many genes

Question 34

DNA

Answer 34

a polymer of repeating nucleotides that makes up chromosomes

Question 35

Nucleotide

Answer 35

the building blocks of DNA made of a nitrogenous base, deoxyribose sugar and a phosphate group

Question 36

Complementary base pairing rule

Answer 36

A bonds with T and C bonds with G

Question 37

Antiparallel nature of DNA

Answer 37

the two strands of DNA run in opposite directions to each other, one runs from 3' (3 prime) to 5' (5 prime) while the other strand runs from 5' to 3'

Question 37

Helicase enzyme

Answer 37

the enzyme that unwinds and unzips DNA strand

Question 38

Leading strand

Answer 38

the DNA strand that is constructed as one continuous strand during
DNA replication

Question 38

DNA replication

Answer 38

making a copy of a DNA strand during cell division

Question 39

Semi-conservative hypothesis

Answer 39

each new strand of DNA consists of one old strand and one new strand

Question 39

Ligase enzyme

Answer 39

joins Okazaki fragments together during DNA replication

Question 40

DNA polymerase enzyme

Answer 40

Binds complementary nucleotides to exposed strands of
DNA during DNA replication

Question 41

Lagging strand

Answer 41

the DNA strand that is formed in small fragments (Okazaki fragments) during DNA replication

Question 42

Mitosis

Answer 42

the type of cell division that results in the formation of two identical daughter cells

Question 43

Homologous pair of chromosomes

Answer 43

a pair of chromosomes that contain the same genes

Question 44

Diploid number

Answer 44

the number of chromosomes found in a normal body cell

Question 45

Haploid number

Answer 45

the number of chromosomes found in a gamete

Question 46

Cell cycle

Answer 46

an orderly sequence of events that occurs from one cell division to the next.

Question 47

Interphase

Answer 47

a part of the cell cycle where the cell carries out its designated function