Michaelmas

Question 1

Difference between breathing and respiration

Answer 1

Breathing- physical process of the intake of oxygen and release of carbon dioxide

Respiration- chemical process that occurs in every cell to release energy

Question 2

Process of breathing

Answer 2

Molecules move from areas of high to low pressure

• intercoastal muscles (contract/relax)
• ribs move (up/down)
• diaphragm muscles (contract/relax)

-Diaphragm (lowers/raised)

-Volume of chest (increases/decreases)

-Pressure in chest (decreases/increases)

-Air pressure in lungs is (lower/greater) than the atmospheric pressure

-Air rushes (in/out) of lungs

Question 3

Composition of air inhaled/ exhaled

Answer 3

Oxygen- 20%, 16%
Carbon Dioxide- 6.04%, 4%
Nitrogen- 79%, 79%

Question 4

Respiration equation

Answer 4

Glucose+ oxygen—> carbon dioxide+ water+ energy

Question 5

What does blood consist of

Answer 5

Red blood cells, white blood cells, platelets and plasma

Question 6

What does plasma contain

Answer 6

Dissolved substances

Question 7

Adaptations of red blood cells to carry oxygen

Answer 7

Biconcave- increases surface area to absorb CO2

Haemoglobin- bonds with O2 to form oxyhaemoglobin

No nucleus- more room for haemoglobin

Question 8

Functions of white blood cells

Answer 8

White blood cells- protection from pathogens (disease- causing organisms)

Phagocytes- can change shape to engulf microbes and digest them

Lymphocytes- can produce antibodies to neutralise microbes

Question 9

Platelets

Answer 9

• Help blood clot
• stop bleeding by forming a scab
• stops further entry of microbes

Question 10

Why does heart rate increase during exercise

Answer 10

• so cardiac output increases
• more blood pumped

-more oxygen and glucose delivered to muscle cells in the body

• muscle cells use these to respire more, to release more energy so they can contract more
• muscle cells also benefit from more oxygen delivered as it means they can avoid anaerobic respiration for longer
• this avoids muscle fatigue

Question 11

Describe 4 functions of the skeleton

Answer 11

• gives the body shape
• allows the body to move
• it protects the major organs
• it produces blood cells

Question 12

Describe different joints and give examples

Answer 12

Ball and socket- movement in all directions, rotation eg. Shoulder, hip

Hinge- forwards/ backwards eg. Knee, elbow

Slightly movable- hold together tightly, slight movement eg. Spine

Immovable- held together by tough fibres, several bones fused together eg. Skull, pelvis

Question 13

Name 5 of the major muscles in the body

Answer 13

Biceps, triceps, quadriceps, hamstrings and calf muscles

Question 14

Describe how antagonistic muscles work

Answer 14

One muscle contracts (gets shorter) and the other muscle relaxes (lengthens)