B3

Question 1

What is epithelial tissue?

Answer 1

A protective or exchange surface formed by tightly packed cells.

Question 2

What is squamous epithelium?

Answer 2

A single layer of flat cells adapted for rapid diffusion in gas exchange.

Question 3

Where is squamous epithelium found?

Answer 3

In the alveoli of the lungs.

Question 4

Why is squamous epithelium efficient for gas exchange?

Answer 4

It is one cell thick with a short diffusion distance.

Question 5

How does COPD affect squamous epithelium?

Answer 5

It damages alveolar walls, reducing surface area and slowing diffusion.

Question 6

What is columnar epithelium?

Answer 6

Tall cells often involved in secretion and protection.

Question 7

What is the role of goblet cells?

Answer 7

To secrete mucus that traps dust and pathogens.

Question 8

What is the role of ciliated cells in the lungs?

Answer 8

To move mucus and trapped particles out of the airways.

Question 9

How do goblet and ciliated cells protect the lungs?

Answer 9

They trap and remove pathogens, preventing infection.

Question 10

What is endothelial tissue?

Answer 10

A thin layer of cells lining blood vessels and the heart.

Question 11

What is the function of endothelial tissue?

Answer 11

Provides a smooth surface to reduce friction and allow efficient blood flow.

Question 12

What damages endothelial tissue?

Answer 12

Smoking, high blood pressure, high LDL cholesterol, diabetes.

Question 13

How does endothelial damage lead to atherosclerosis?

Answer 13

Damage allows cholesterol and inflammatory cells into the artery wall, forming plaques that narrow arteries.

Question 14

What is the microscopic structure of skeletal muscle?

Answer 14

Long multinucleate fibres containing myofibrils made of actin and myosin arranged in sarcomeres.

Question 15

What are myofibrils?

Answer 15

Bundles of actin and myosin filaments responsible for contraction.

Question 16

What is a sarcomere?

Answer 16

The basic contractile unit of a myofibril.

Question 17

What are fast-twitch muscle fibres specialised for?

Answer 17

Rapid, powerful contractions but fatigue quickly.

Question 18

What are slow-twitch muscle fibres specialised for?

Answer 18

Endurance and aerobic respiration.

Question 19

Why do slow-twitch fibres contain many mitochondria?

Answer 19

To support sustained aerobic respiration.

Question 20

Why do fast-twitch fibres fatigue quickly?

Answer 20

They rely on anaerobic respiration, producing lactic acid.

Question 21

Which sports rely on fast-twitch fibres?

Answer 21

Sprinting, weightlifting.

Question 22

Which sports rely on slow-twitch fibres?

Answer 22

Long-distance running, cycling.

Question 23

What is nervous tissue?

Answer 23

Tissue composed of neurones and supporting cells that transmit electrical impulses.

Question 24

What are myelinated neurones?

Answer 24

Neurones with a myelin sheath insulating the axon.

Question 25

What are non-myelinated neurones?

Answer 25

Neurones without a myelin sheath; impulses travel more slowly.

Question 26

What is an action potential?

Answer 26

A rapid change in membrane potential transmitted along the axon.

Question 27

What is the refractory period?

Answer 27

A brief time when a neurone cannot fire again, ensuring one-way transmission.

Question 28

What does the P wave on an ECG represent?

Answer 28

Atrial depolarisation.

Question 29

What does the QRS complex represent?

Answer 29

Ventricular depolarisation.

Question 30

What does the T wave represent?

Answer 30

Ventricular repolarisation.

Question 31

What is a synapse?

Answer 31

A junction where a neurone communicates with another cell using neurotransmitters.

Question 32

What is a neurotransmitter?

Answer 32

A chemical messenger released across a synapse.

Question 33

What is the role of acetylcholine?

Answer 33

It binds to receptors on the postsynaptic membrane to trigger a response.

Question 34

What happens to acetylcholine after release?

Answer 34

It is broken down by enzymes and recycled.

Question 35

How can neurotransmitter imbalances cause illness?

Answer 35

They disrupt signalling and contribute to conditions like Parkinson’s or depression.

Question 36

What neurotransmitter is low in Parkinson’s disease?

Answer 36

Dopamine.

Question 37

What neurotransmitter imbalance is linked to depression?

Answer 37

Low serotonin levels.

Question 38

How do drugs affect synaptic transmission?

Answer 38

They can block, mimic, or enhance neurotransmitters.

Question 39

What is L-Dopa used for in Parkinson’s treatment?

Answer 39

It is converted into dopamine in the brain to improve movement control.

Question 40

What is the microscopic structure of skeletal muscle?

Answer 40

Muscle fibres contain myofibrils made of repeating sarcomeres with actin and myosin filaments.

Question 41

What is a sarcomere?

Answer 41

The contractile unit of muscle where actin and myosin overlap and slide to cause contraction.

Question 42

How does filament sliding lead to contraction?

Answer 42

Myosin heads pull actin inward, shortening the sarcomere.

Question 43

How does low dopamine affect the brain?

Answer 43

Reduced dopamine disrupts motor control, causing Parkinson’s symptoms like tremors and stiffness.

Question 44

How does low serotonin affect mental health?

Answer 44

Serotonin imbalance affects mood regulation and can contribute to depression.

Question 45

What is the role of L-Dopa in Parkinson’s disease?

Answer 45

It is converted to dopamine in the brain to improve motor function.

Question 46

How can drugs alter synaptic transmission?

Answer 46

By mimicking neurotransmitters, blocking receptors, inhibiting reuptake, or preventing enzyme breakdown.