B3

Question 1

Rosalind Franklin

Answer 1

Kings college
Obtained X-Ray data
Showed DNA double helix

Question 2

4 bases

Answer 2

A + T

G + C

Question 3

What do triplet codons specify

Answer 3

Specific amino acids

Question 4

How are copies of genes made

Answer 4

mRNA (single strand molecule) carries copy of one strand of length of DNA

Question 5

What 6 things are made of collagens

Answer 5

Skin
Bones
Cartilage
Tendons
Ligaments
Walls of blood vessels

Question 6

What are collagens

Answer 6

Structural proteins

Question 7

Symbol equation for aerobic respiration

Answer 7

C6H12O6 + 6O2. –> 6CO2 + 6H2O

Question 8

Formula for respiratory quotient

Answer 8

RQ=. Volume CO2 produced / volume O2 consumed

Question 9

Why does heart rate increase during exercise

Answer 9

To deliver more oxygen and glucose to muscles per minute

Question 10

Why breathing rate increases during exercise

Answer 10

Remove extra CO2 more quickly

Question 11

What is metabolic rate

Answer 11

A measure of how quickly all the chemical reactions are going on in an organism

Question 12

Anaerobic respiration equation

Answer 12

Glucose -> lactic acid + energy

Question 13

Why does anaerobic respiration happen

Answer 13

When doing hard exercise, heart rate doesn’t go up quick enough
Not enough oxygen
Muscles need energy

Question 14

Why can’t anaerobic exercise happen for long

Answer 14

Lactic acid is toxic

Question 15

How does the pH change effect enzymes and respiration

Answer 15

Increased lactic acid lowers pH
Reduces enzyme activity
Reduces rate of respiration
Muscles get fatigued
Muscles stop contracting

Question 16

What happens when one stops exercising

Answer 16

Heart rate stays high
Blood quickly carries lactic acid to liver

Pants
Extra oxygen deals with lactic acid in liver

Question 17

What is oxygen debt

Answer 17

Amount of oxygen needed to deal with lactic acid

Question 18

Why do body cells divide

Answer 18

To replace worn out cells
To repair damaged tissue
To grow

Question 19

How does DNA replicate

Answer 19

DNA is a double stranded molecule
Molecule 'unzips' forming 2 strands
Exposes DNA bases
Spare bases in nucleus line up against separated strand
Align only by complimentary DNA base
1 molecule has become 2

Question 20

Benefits of being multicellular

Answer 20

Can be larger
Different cells with different jobs
Can be complex

Question 21

Name of gamete cell division

Answer 21

Meiosis

Question 22

Watson and Crick

Answer 22

1953
Cambridge
Worked out structure of DNA

Question 23

Size of red blood cells

Answer 23

Small in diameter
Relatively thick
Large SA:V so lots of oxygen can diffuse through

Question 24

Shape of red blood cells

Answer 24

Biconcave discs

Increases SA:V

Question 25

How blood leaves the heart

Answer 25

In arteries

At high pressure

Question 26

How does blood return to the heart

Answer 26

Through the veins

Question 27

Structure of arteries

Answer 27

Thick, muscular, elastic wall
Withstand high pressure
Small lumen

Question 28

Structure of veins

Answer 28

Thinner walls
Larger lumen
Valves

Question 29

How does blood travel (route)

Answer 29

Left side(ventricle) -> body -> right side (atrium -> ventricle) -> lungs -> left side (atrium -> ventricle)

Question 30

How can plant growth be measured

Answer 30

Increase in length
Wet mass
Dry mass