AQA Combined Science Biology Paper 1

Name the two types of Eukaryotic cells

Plant cells, animal cells

What type of cells are Prokaryotic cells?

Bacteria cells

Where are chromosomes found in an animal cell

Nucleus

Describe the DNA in a bacteria cell

A single DNA loop or a DNA ring (plasmid)

What is 'centi' in standard form?

10 to the power of -2

What is 'milli' in standard form?

10 to the power of -3

What is 'micro' in standard form?

10 to the power of -6

What is 'nano' in standard form?

10 to the power of -9

List the five parts of an animal cell

Nucleus, Cytoplasm, Cell membrane, Mitochondria, Ribosomes

List the three parts of a cell only found in plant cells

Vacuole (filled with cell sap), Chloroplasts, Cell wall

What is a cell wall made of in a plant cell?

Cellulose

What function does cellulose have in a cell wall?

Provides strength

Name three specialised animal cells

Sperm, Nerve, Muscle

Name three specialised plant cells

Xylem, Root hair, Phloem

What is cell differentiation?

The process in which cells become specialised perform specific functions in the organism.

State two benefits of an electron microscope over a light microscope

Greater resolving power, Higher magnification

How do you calculate magnification in a microscope?

Magnification = size of image/size of real object

What is a stem cell?

An undifferentiated cell

Name two conditions that treatment with stem cells might help in humans

Diabetes, Paralysis

What is a risk of using stem cells to treat humans?

Transfer of viral infection

What is diffusion?

Spreading out of particles of a substance in solution or a gas

What process moves substances into and out of a cell across a cell membrane?

Diffusion

What does diffusion result in?

The net movement of particles from an area of higher concentration to an area of lower concentration

Name two substances transported in and out of cells during gas exchange

Oxygen, Carbon Dioxide

What waster product diffuses into blood plasma?

Urea

Which organ is urea excreted from?

The kidney

Name three factors that affect diffusion

Difference in concentration (concentration gradient), Temperature, Surface area of membrane

How does water move across cell membranes?

By osmosis

What is osmosis?

Diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane

What is active transport?

The movement of substances from a more dilute solution to a more concentrated solution

What's the role of active transport in plants?

The absorption of mineral ions from dilute solutions in soil via root hairs

What's the role of active transport in humans?

Allows sugar molecules to move from the gut into the blood

What are the basic building blocks of all living organisms?

Cells

What is a tissue?

A group of cells with similar structure and function

What is an organ?

An aggregation of tissues that perform a specific function

What is an organ system?

Different organs working together

Name the parts of the digestive system

Mouth salivary glands, stomach, liver, gall bladder, small intestine, large intestine

Where are amylases produced?

Salivary glands

What does amylase do?

Breaks down starch into sugars

Where are proteases produced?

Stomach, small intestine, pancreas

What do proteases do?

Break down proteins into amino acids

Where are lipases produced?

Break down fats into glycerol and fatty acids

What do lipases do?

Break down lipids (fats) into glycerol and fatty acids

Where is bile produced?

In the liver

Where is bile stored in the body?

Gall bladder

Is bile acidic or alkaline?

Alkaline

What does bile do?

Neutralised hydrochloric acid in the stomach, emulsifies fats into small droplets to increase surface area

What does the heart do?

Pumps blood around the body in a double circulatory system

Name the five blood vessels associated with the heart

Aorta, Vena cava, Pulmonary artery, Pulmonary vein, Coronary arteries

What does the aorta do?

Pumps blood around the body

What does the vena cava do?

Pumps blood from the body to the heart

What does the pulmonary artery do?

Carries deoxygenated blood from the heart to the lungs

What does the pulmonary vein do?

Carries oxygenated blood from the lungs to the heart

What is natural resting heart rate?

60-100 bpm

Why might you need an artificial pacemaker?

To correct irregularities in the heart rate

Name the three different types of blood vessel

Arteries, veins, capillaries

What is blood?

A tissue consisting of plasma where red blood cells, white blood cells and platelets are suspended

What do red blood cells do?

Carry oxygen around the body

What do white blood cells do?

Defend against infection

What do platelets do?

Help blood clot

What does plasma do?

It's the liquid that carries everything in the blood

What is cardiovascular disease?

A term used to describe diseases of the heart or blood vessels

What are the three risk factors associated with cardiovascular disease?

Diet, Smoking, Exercise

What is the risk factor associated with Type 2 Diabetes?

Obesity

What is cancer?

The result of changes in cells that leads to uncontrolled growth and division

What is a benign tumour?

The growth of abnormal cells that are contained in one area and do not invade other parts of the body

What is a malignant tumour?

Cancers that invade neighbouring tissues and spread to different parts of the body in blood

List the six types of tissue

Epidermal, Palisade mesophyll, Spongy mesophyll, Xylem, Phloem, Meristem

What is epidermal tissue?

Tissue that covers the whole plant

What is palisade mesophyll?

The part of the leaf where most photosynthesis takes place

What is spongy mesophyll?

A part of the leaf that contains big air spaces to allow gases to diffuse in and out of cells

What is xylem?

A hollow tube that takes water and mineral ions up to the stem and leaves from the roots

What is phloem?

A hollow tube that transports food between the roots and the stem and leaves

What is transpiration?

The loss of water from a plant by evaporation and diffusion

What is translocation?

The movement of food molecules through phloem tissue

What is the structure of xylem?

Hollow tubes strengthened by lignin

What is the role of xylem?

To transport water and mineral ions from the roots to stems and leaves

What is the role of guard cells and stomate in leaves?

To control gas exchange and water loss

What is the structure of phloem?

Tubes of elongated cells

What are pathogens?

Microorganisms that cause infectious diseases

List the four types of pathogen

Viruses, Bacteria, Protists, Fungi

Name the three ways that pathogens can be spread

Direct contact, by water, by air

What is a virus?

A small part of DNA in a protein coat that replicates inside cells

What are bacteria?

Very small living cells

What is a protist?

Single-celled eukaryotes

How do viruses reproduce inside the body?

Inside cells using the cells machinery to replicates themselves and then causing the cell to burst to release the new viruses

How do bacteria reproduce inside the body?

Very quickly and by division

How can bacteria make a person feel ill?

By producing toxins that damage cells and tissues

How can a virus make a person feel ill?

The cell damage makes you feel ill

What is measles?

A viral disease showing symptoms of fever and a red skin rash that can be fatal if complications arise

How is measles spread?

By inhalation droplets from sneezes and coughs

How is measles prevented?

By vaccination of young children

What is HIV?

A viral disease spread by sexual contact or by exchange of bodily fluids

When does AIDS occur?

When the body's immune system becomes so badly damaged it can no longer deal with other infections or cancers

What is TMV?

Tobacco Mosaic Virus

What are the symptoms of TMV?

A distinctive 'mosaic' pattern of discolouration on leaves of plants that prevents photosynthesis affecting growth

What is salmonella?

Food poisoning spread by bacteria ingested in food or on food prepared in unhygienic conditions

What are the symptoms of salmonella poisoning?

Fever, abdominal cramps, vomiting, diarrhoea

What is gonorrhoea?

A sexually transmitted disease (STD) with symptoms of a thick yellow or green discharge from the vagina or penis and pain on urinating

How is gonorrhoea treated?

By antibiotics such as penicillin though some strains are now resistant to antibiotics