Paper 1

Question 1

What is a eukaryotic cell? What’s a prokaryote cell?

Answer 1

A eukaryotic cell is an animal or plant cell. Prokaryotes are bacteria.

Question 2

What is the cell cycle?

Answer 2

Stage 1) Cells grow bigger, increase mass, and replicate their DNA
Stage 2) Mitosis- One set of chromosomes is pulled to each end of the dividing cell and the nucleus divides
Stage 3) Cytoplasm and cell membrane divide to form two identical daughter cells

Question 3

What’s the tests for starch, carbohydrates, lipids and protein?

Answer 3

Carbohydrates- Benedict solution (blue to orange)
Starch- Iodine (turns blue black)
Lipids- Ethanol (cloudy white layers)
Proteins- Biuret (turns purple)

Question 4

What is the structure of the lungs?

Answer 4

Diaphram-contracts to increase volume
Alveoli- incases surface area
Lung- organ
Intercostal muscles- contracts to pull ribcage
Trachea- carries air to and from lungs
Bronchus-carries air in or out of lungs
Bronchioles- carries air to alveoli

Question 5

How does a stent reduce the risk of coronary heart disease?

Answer 5

It keeps open the narrow or blocked artery, to keep blood flowing and limit the buildup of fatty tissue

Question 6

How does statins reduce the risk of coronary heart disease?

Answer 6

It reduces cholesterol levels, which limits any buildup in arteries

Question 7

What does the phloem and xylem transport?

Answer 7

Xylem transports water and mineral ions. Phloem transports glucose/food.

Question 8

What factors affect the transpiration rate?

Answer 8

Light intensity, temperature, air flow, and humidity

Question 9

How are communicable pathogens spread?

Answer 9

Direct contact, air by droplets, and water

Question 10

How can the spread of disease be reduced?

Answer 10

Improving hygiene, destroying or controlling vectors, vaccination, and isolating the infected.

Question 11

Rose Black Spot a fungal, viral, or bacterial disease?

Answer 11

Fungal

Question 12

How does the human body defend itself against disease/pathogens?

Answer 12

Skin- acts as a barrier, produces antimicrobial secretions to kill the pathogens
Nose, trachea, and bronchi- produces mucus that traps the pathogens from the air
Stomach- the acid kills any pathogens in food or drink, or in mucus
White blood cells- Phagocytes (engulf the pathogen) and lymphocytes (which produce antibodies)

Question 13

What do plants need nitrate ions for?

Answer 13

Protein production, which is used in growth. A lack of nitrates means protein production is limited, which may lead to stunted growth

Question 14

What do plants need magnesium ions for?

Answer 14

To make chlorophyll. The leaves may become yellow and growth slows down in a process called chlorosis, if there isn’t enough magnesium.

Question 15

What are some plant defences against pathogens and herbivores?

Answer 15

Mimicry, drooping, hairy stems, thorns or spikes, bakr, and a tough waxy cuticle.

Question 16

How does vaccination work?

Answer 16

1) Small amounts of dead pathogens are injected
2) Antigens in vaccine stimulate white blood cells to produce antibodies to destroy the pathogens
3) When exposed to a live version, the body can respond rapidly and create the correct antibody.

Question 17

What happens in Phase 1, 2, and 3 when testing new drugs?

Answer 17

Phase 1) To work out a safe dosage
Phase 2) To work out side effects
Phase 3) A double blind trial is used. A placebo is used to see how effective the drug actually is

Question 18

How are monoclonal antibodies made?

Answer 18

1) A mouse is vaccinated to produce antibodies. Spleen cells that form antibodies are collected by operation on the mouse
2) The lymphocytes (spleen cells) are fused with tumour cells (myeloma cells)
3) A hyidoma cell is formed. The tumour cell can divide quickly, but also produce antibodies
4) The cell is cloned in a lab. The antibodies are collected, purified and ready for use

Question 19

What are some advantages and disadvantages of monoclonal antibodies?

Answer 19

Advantages) Healthy cells aren’t affected, it only binds to the specifically diseased or damaged cells.
Disadvantages) Created more side effects than expected. The mouse antibodies may trigger an immune reaction in humans

Question 20

Do painkillers help to kill the pathogens?

Answer 20

No. It treats the symptoms of disease.

Question 21

Can antibiotics kill viruses?

Answer 21

No. Viruses reproduce inside cels, bursting them. Antibiotics only kill bacteria.

Question 22

What’s the difference between benign and malignant tumours?

Answer 22

Benign form in one place and don’t spread

Malignant invade neighbouring tissues by moving through bloodstream

Question 23

What is glucose used for?

Answer 23

Respiration, making fruits, making cellulose for cell walls, making proteins, and to store in seeds or as starch.

Question 24

How is lactic acid removed?

Answer 24

Oxygen is needed to break it down, the amount of oxygen needed is known as the oxygen debt. Blood flowing through the muscles transports lactic acid to the liver, where it’s converted back to glucose.