Y10 Science Mocks Revision

Question 1

What is a pathogen?

Answer 1

A microorganism that causes disease

Question 2

What are viruses?

Answer 2

• DNA/RNA surrounded by a protein coat
• Viruses live and reproduce inside cells causing damage
• Examples of viruses: cold, influenza, measles, HIV, tobacco mosaic virus

Question 3

What is bacteria?

Answer 3

• Made of prokaryotic cells
• No membrane bound organelles (no chloroplasts, mitochondria or nucleus)
• Have a cell wall and are single celled organisms
• Examples of bacteria: tuberculosis (TB), salmonella, gonorrhoea

Question 4

What are protists?

Answer 4

• Membrane bound organelles
• Usually single celled
• Examples of protists: dysentery, sleeping sickness, malaria

Question 5

What are fungi?

Answer 5

• Membrane bound organelles
• Cell wall made of chitin
• Single celled or multi cellular
• Examples of fungi: athletes foot, thrush, rose black spot

Question 6

What are communicable diseases?

Answer 6

Diseases that can be spread from person to person

Question 7

Give some examples of communicable diseases. Include the method of transmission and how they can be controlled

Answer 7

Disease Pathogens. Symptoms. Method of Control of
Transmission Spread

Measles Virus. Fever, red. Droplet infection Vaccine
skin rash. from sneezes/coughs

HIV. Virus. Flu like symp. Sexual contact/. Anti-retro
-toms, damage. exchange of viral drugs
to immune system body fluids /condoms

Tobacco Mos. Virus Mosaic pattern. Enters wounds. Remove infe
aic Virus. on leaves. in epidermis cted leaves

Salmonella Bacteria Fever, cramps, vo- Food prepared Improve foo
miting, diarrhoea in unhygienic d hygiene
conditions

Gonorrhoea Bacteria Green discharge from. Sexual contact/. Use condo
penis/vagina exchange of body ms/antibo
fluids tics

Malaria. Protists Recurrent fever. By an animal Prevent
vector mosquito br
eeding

Rose Black. Fungus. Purple/Black spots on. Spores from Remove infe
Spot. leaves. wind/water. cted leaves

Question 8

Name some non-specific defence systems that the body has

Answer 8

• Nose: Nasal hairs, sticky mucus and cilia prevent pathogens entering through the nostrils
• Trachea and bronchus (respiratory system): Lined with mucus to trap dust and pathogens. Cilia move the mucus upwards to be swallowed
• Stomach Acid: Stomach acid (pH 1) kills most ingested pathogens
• Skin: Hard to penetrate waterproof barrier. Glands secrete oil which kill microbes

Question 9

How are pathogens identified?

Answer 9

Pathogens are identified by white blood cells by the different proteins on their surfaces called antigens

Question 10

Name the components of white blood cells that fight pathogens and describe how they do so

Answer 10

Phagocytes: Phagocytosis - Phagocytes engulf the pathogens and digest them

Lymphocytes: Antibody Production - Specific antibodies destroy the pathogen. This takes time so an infection can occur. If a person is infected again by the same pathogen, the lymphocytes make antibodies much faster
Antitoxin Production - Antitoxin is a type of antibody produced to counteract the toxins produced by bacteria

Question 11

Name the different ways plants have of defending themselves from illness

Answer 11

Physical: Thick waxy layers, cell walls stop pathogen entry
Mechanical: Thorns, curling up leaves to prevent being eaten
Chemical: Antibacterial and toxins made by plant

Question 12

1) What are some symptoms of plant diseases
2) How would you identify plant disease

Answer 12

1) Stunted growth (nitrate ions needed for protein synthesis - lack of nitrate = stunted growth), spots on leaves, area of decay, growths, malformed stem/leaves, discolouration (magnesium ions needed to make chlorophyll - not enough leads to chlorosis - leaves turn yellow), presence of pests

2) Reference using gardening manual or website, laboratory test for pathogens, testing kit using monoclonal antibodies

Question 13

What are non-communicable diseases

Answer 13

Diseases that can’t be spread from person to person

Question 14

What is cancer?

Answer 14

• The result of changes in DNA that lead to uncontrollable growth and division
• Some cancers have genetic risk factors
• Carcinogens and ionising radiation increase the risk of cancer by changing/damaging DNA
• Risk factors for cancer include drinking alcohol, diet, obesity and smoking
• These factors can also cause heart/lung disease and effect the brain, liver and health of unborn babies

Question 15

Name the two types of tumours that cause cancer

Answer 15

Benign tumour - Contained in one area of the body (usually by a membrane) - not cancerous
Malignant tumour - Invade tissues and spread to different parts of the body to form secondary tumours - cancerous

Question 16

What are antibiotics and painkillers?

Answer 16

Antibiotics: Kill infective bacteria inside the body. Specific bacterial infections require specific antibiotics (eg penicillin)
Painkillers (+ other medicines): Drugs that are used to treat the symptoms of a disease. They don’t kill pathogens (eg aspirin, paracetamol, ibuprofen)

Question 17

Why can antibiotics not be used to treat viruses?

Answer 17

It’s difficult to develop drugs to kill viruses without harming body tissues because viruses live and reproduce inside cells

Question 18

How can certain types of bacteria become resistant to antibiotic drugs?

Answer 18

Because bacteria can mutate and in certain cases this has made them resistant to antibiotics and drugs

Question 19

Define vaccine/vaccination

Answer 19

Used to immunise a large portion of the population to a disease to prevent the spread of a pathogen by injecting people with a small dose of a dead or inactive pathogen

Question 20

How does vaccination work?

Answer 20

1st infection by pathogen: White blood cells detect pathogens in the vaccine. Antibodies are released into the blood
Re-infection by the same pathogen: White blood cells detect pathogens. Antibodies are made much faster and in larger amounts

This works as a person is unlikely to suffer the symptoms of the harmful disease and it’s spread in a population is prevented

Question 21

How are drugs made?

Answer 21

Today most new drugs are synthesised by chemists in the pharmaceutical industry. However, traditionally drugs were extracted from plants and microorganisms.

Question 22

Give some examples of drugs that have been extracted from plants

Answer 22

Digitalis: Extracted from foxgolve plants and used as a heart drug
Aspirin: A painkiller/anti-inflammatory drug that was first found in willow bark
Penicillin: Discovered by Alexander Fleming from the Penicillium mould and used as an antibiotic

Question 23

What are drugs extensively tested for?

Answer 23

Efficiency: Making sure the drug works
Toxicity: Check that the drug isn’t poisonous
Dose: The most suitable amount to take

Question 24

What are preclinical trials?

Answer 24

Preclinical trials use cells, tissues and live animals as test subjects before they move onto human trials. Must be carried out before the drug can be tested on humans.

Question 25

How do drug trials work?

Answer 25

Drugs have to be tested and trialled before to check they’re effective and safe. Clinical trials use healthy volunteers and patients. Stage 1: Healthy volunteers try a small dose of the drug to check it’s safe and record any side effects Stage 2: A small number of patients try the drug at a low dose to see if it works Stage 3: A larger number of patients; different doses are trialled to find the optimum dose Stage 4: A double blind trial will occur. The patients are divided into groups. Some will be given the drug and others a placebo (a placebo can look identical to the new drug but contain no active ingredients)

Question 26

What are double blind trials?

Answer 26

A double blind trial is a trial in which both patients and doctors don’t know who receives the new drug and who receives a placebo until the end of the trial. This prevents bias during testing

Question 27

What are monoclonal antibodies?

Answer 27

Identical copies of one type of antibody produced in a laboratory. They are specific to one binding site on an antigen. Can target specific chemicals or cells in the body.

Question 28

Describe how monoclonal antibodies work?

Answer 28

1) A mouse is injected with a pathogen 2) Lymphocytes produce antibodies 3) Lymphocytes are removed from the mouse and fused with rapidly dividing mouse tumour cells 4) The new cells are called hybridomas 5) The hybridomas divide rapidly and release lots of antibodies which are then collected

Question 29

How can monoclonal antibodies be used?

Answer 29

- Diagnosis: pregnancy test - measure hormone levels - Detecting pathogens: can detect very small quantities of chemicals in the blood - Detecting molecules: fluorescent dye can be attached so it can be seen inside cells/tissues - Treatment: bound to radioactive substance, toxic drug or chemical. Cancer cells are targeted too. Normal body cells are unharmed

Question 30

What’s the problem with using monoclonal antibodies?

Answer 30

They can create more side effects than expected (in some cases they can even be fatal) and are not as widely used as everyone hoped they would be when they were first developed

Question 31

What is the equation for calculating the magnification of an image?

Answer 31

Magnification = size of image / size of real object

Question 32

What are the differences between prokaryotes and eukaryotes?

Answer 32

Eukaryotes contain their genetic material in the nucleus whereas prokaryotes don’t. They’re also bigger than prokaryotes

Question 33

What parts do most animal cells have?

Answer 33

Nucleus, cell membrane, cytoplasm, ribosomes and mitochondria

Question 34

What do plants often have that animal cells don’t?

Answer 34

Cell wall, permanent vacuole and chloroplasts

Question 35

Why do plants need chloroplasts?

Answer 35

To produce chlorophyll for photosynthesis

Question 36

Which chemical reaction takes place in mitochondria?

Answer 36

Respiration

Question 37

How many chromosomes are in a human nucleus?

Answer 37

42

Question 38

Which type of cell division is involved in replacing body cells?

Answer 38

The cell division that replaces body cells is called mitosis

Question 39

Which type of cell division is involved in the production of gametes?

Answer 39

The cell division that produces gametes is meiosis

Question 40

Give an example of a specialised cell

Answer 40

Nerve cell, sperm cell, root hair cell, muscle cell etc.

Question 41

Put these in order of size (starting with the smallest): organ, tissue, organ system, cell

Answer 41

Cell, tissue, organ, organ system

Question 42

What are the differences between malignant and benign tumours?

Answer 42

A malignant tumour is cancerous while a benign tumour isn’t

Question 43

What are stem cells?

Answer 43

A stem cell is a cell that can produce other cells of the same type

Question 44

What is the word equation for aerobic respiration?

Answer 44

Oxygen + Glucose — Light —> Water + Carbon Dioxide

Question 45

What is the symbol equation for aerobic respiration?

Answer 45

O2 + C6 H12 O6 — Light —> H2O + CO2

Question 46

What is the word equation for anaerobic respiration in animal cells?

Answer 46

Glucose ——> Lactic Acid

Question 47

What is the equation for fermentation, by yeast cells and some other microorganisms?

Answer 47

Glucose ——> Ethanol + Carbon Dioxide

Question 48

Which type of pathogen cannot be killed by antibiotics?

Answer 48

Viruses

Question 49

Write a definition for diffusion

Answer 49

Diffusion is the movement of particles from a high concentration to a low concentration

Question 50

Write three factors that affect the rate of diffusion

Answer 50

Concentration gradient, membrane permeability and temperature

Question 51

How do you calculate the surface area:volume ratio?

Answer 51

To calculate the surface area:volume ratio you divide the surface area by the volume

Question 52

What is osmosis?

Answer 52

Osmosis is the diffusion of water molecules from a high to low concentration through a partially permeable membrane

Question 53

What is active transport?

Answer 53

Active transport is where molecules are transported against the concentration gradient

Question 54

Give an example of something that is taken into an organism by active transport

Answer 54

Active transport moves ions from the soil into root hair cells

Question 55

Describe how enzymes work

Answer 55

Enzymes break down food molecules to allow them to be absorbed by the body

Question 56

What is the name of the enzymes that break down carbohydrates?

Answer 56

Amylase

Question 57

What is the name of the enzymes that break down proteins?

Answer 57

Protease

Question 58

What is the name of the enzymes that break down lipids?

Answer 58

Lipases

Question 59

What is the role of bile?

Answer 59

Bile emulsifies lipids to increase surface area and the rate of lipid breakdown by lipase. It also changes the pH level to neutral for lipase to work

Question 60

What are the three types of blood vessel?

Answer 60

Veins, capillaries + arteries

Question 61

What does blood contain?

Answer 61

Red blood cells, white blood cells, plasma, platelets

Question 62

Write a risk factor for coronary heart disease

Answer 62

Smoking, poor diet etc.

Question 63

Which plant tissue transports water?

Answer 63

Xylem transports water and minerals around the plant

Question 64

Which plant tissue transports dissolved sugars?

Answer 64

Phloem transports dissolved sugars from the leaves to the rest of the planet (translocation)

Question 65

What are the four types of pathogen?

Answer 65

Viruses, bacteria, protists and fungi

Question 66

Give an example of each type of pathogen

Answer 66

Virus: influenza Bacteria: salmonella Protist: dysentery Fungus: athletes foot

Question 67

What can white blood cells do to defend the body against pathogens?

Answer 67

They can defend the body by producing antibodies or killing pathogens

Question 68

What does a vaccine contain?

Answer 68

Vaccines contain a small amount of dead/inactive form of whatever pathogen a person’s being vaccinated against

Question 69

What is the word equation for photosynthesis?

Answer 69

Carbon Dioxide + Water — Light —> Oxygen + Glucose

Question 70

What is the symbol equation for photosynthesis?

Answer 70

CO2 + H2O — Light —> O2 + C6 H12 O6

Question 71

Write five limiting factors of photosynthesis

Answer 71

Temperature, light intensity, carbon dioxide, carbon dioxide concentration + amount of chlorophyll

Question 72

Write three things that the body maintains within a small range inside the body, as part of homeostasis

Answer 72

Blood glucose concentration, body temperature + water levels

Question 73

Put the following parts of a nervous response in order: coordinator, response, receptor, effector, stimulus

Answer 73

Stimulus, receptor, coordinator, effector + response

Question 74

Which gland is known as the master gland?

Answer 74

The pituitary gland

Question 75

Which hormone reduces the concentration of glucose in the blood?

Answer 75

Insulin

Question 76

Where is glucose stored in the body?

Answer 76

In the liver and muscles

Question 77

What is glucose stored as (a larger, insoluble molecule)?

Answer 77

In the liver and skeletal muscles

Question 78

Which hormone results in an increase in the blood glucose concentration?

Answer 78

Glucagon

Question 79

Which type of diabetes can be caused by a high fat diet and lack of exercise?

Answer 79

Type 2 diabetes

Question 80

What does IVF stand for?

Answer 80

In Vitro Fertilisation

Question 81

Which two hormones do fertility drugs contain?

Answer 81

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH)