B1 aqa revision cards

What do we mean by a balanced diet?

A diet which contains equal amounts of all the nutrients needed for a healthy body.

Give three reasons to explain why a person may be malnourished:

- Too much energy

- Too little food

- Missing nutrients

Name the two main effectors in the human body:

- Glands

- Muscles

Name three stimuli which effect humans:

- Light

- Sound

- Touch

Name two very addictive drugs:

- Cocaine

- Heroine

What is meant by a double blind trial?

When neither the doctor nor the patient knows who has had the drug and who has had the placebo.

State three things that plants compete for:

- Light

- Water

- Nutrients

Why do warning colours prevent some animals from being eaten?

Because it sends a signal saying that the animal is either poisonous or won't taste nice.

What does the word biomass mean?

The mass of living material.

Give an example of a detritus feeder:

- Worm

In what way are embryo transplants similar to what happens when identical twins form.

Transplants- the embryo splits several times

Twins- The embryo splits into two

What is meant by evolution?

The idea that organisms have developed from simple life forms and changed over time to suit their lifestyle.

Why did it take so long for Darwin's theory to be accepted?

- Scientists didn't have enough evidence

- It went against the idea that God created all living things.

What is a pathogen?

An organism that causes disease.

What is meant a mutation of a pathogen?

A change in the gene

Why don't doctors give antibiotics for mild throat infectioons?

Because the body heals itself and if used often it could become resistant to the antibiotics.

How does a person develop immunity following vaccination?

The white blood cells produce antibodies.

How are impulses transmitted across a synapse?

Through means of chemicals.

Describe the sequence of events in a reflex action.

Stimulus - Receptor - Sensory neurone - Relay neurone - Motor neurone - Effecter - Response. 

Why are FSH and LH given in fertility treatment?

FSH matures the egg.

LH stimulates ovulation