June 2013 wjec unit 1

Question 1

H2N?

Answer 1

amino group

Question 2

COOH?

Answer 2

carboxyl group

Question 3

2 peptides joined together?

Answer 3

dipeptide molecule

Question 4

C-N?

Answer 4

peptide bond

Question 5

Bonds in a protein molecule?

Answer 5

Hydrogen bond

Question 6

Shape in protein molecule?

Answer 6

alpha helix

Question 7

Level of protein structure?

Answer 7

secondary

Question 8

Theory where active site and substrate are complementary?

Answer 8

Lock and theory hypothesis

Question 9

Theory represents activity of lysozome?

Answer 9

induced fit theory

Question 10

What do substrate + enzymes form?

Answer 10

enzyme substrate complexes

Question 11

How do enzymes bring about the effect of speeding up a reaction?

Answer 11

by lowering their activation energy

Question 12

Characteristic of an enzyme at the end of a reaction ?

Answer 12

active site remains unchanged/ stays the same shape

Question 13

3 factors which affect enzyme activity?

Answer 13

temperature
pH
substrate concentration

Question 14

Intracellular and extracellular enzymes?

Answer 14

intracellular means inside of cell
extracellular means outside of cell

Question 15

Nuclelous def?

Answer 15

synthesis of ribosomes

Question 16

Nuclear envelope?

Answer 16

Separates the DNA of the nucleus from the cytoplasm

Question 17

Differences between 2 different types of endoplasmic reticulum?

Answer 17

D - rough as parallel membranes containing ribosomes that for attached
E - smooth irregular pattern to the membranes doesn’t contain ribosomes

Question 18

Where does mitosis occur during plants?

Answer 18

meristem

Question 19

One stage of the cell cycle is present in greater numbers than others?

Answer 19

interphase
longest part of the cel cycle

Question 20

How does meiosis differ from mitosis?

Answer 20

meiosis produces genetically identical cells whereas meiosis produces genetically different cells
meiosis produces haploid jowever mitosis produces diploid cells

Question 21

Lipid bilayer def?

Answer 21

2 layers of phospholipids

Question 22

What are the hydrophobic parts?

Answer 22

fatty acid tails

Question 23

2 functions of membrane proteins?

Answer 23

channel proteins
carrier proteins

Question 24

Why the changes in red blood cellmembranes caused by DOX make it more toxic than IDA?

Answer 24

membranes proteins change shape
doesnt allow the transport of molecules is reduced or stopped by the fluidity of the blood cell reduced they cant flow through a capillary as easily

Question 25

Cancer def?

Answer 25

Uncontrolled mitosis

Question 26

Why is it important that the tertiary structure of these enzymes is not altered by cross linking?

Answer 26

Dont cause a change in the active sites because the substrate cannot fit in / bind and cannot form enzyme substrate complexes

Question 27

Why is it necessary for these enzymes aggregates to be insoluble?

Answer 27

So they dont mix with the product
If they were soluble, it would go through the fewer and therefore wont mix with the product

Question 28

3 advantages of immobilised enzymes?

Answer 28

reuse them in easily
can be used over a wide range of temperatures
can be used over a wide range of pH

Question 29

Another method of immobilising enzyme?

Answer 29

algenate beads

Question 30

Term used to describe the appearance of the cells in 0.0M?

Answer 30

turgid

Question 31

Determine the water potential of potato tissue?

Answer 31

where the graph crosses the x axis, water potential of the cell is equal to the sucrose concentration

Question 32

Diagram of the cell i 1M solution?

Answer 32

Cell wall
cytoplasm has shrunk
vacuole has shrunk