Set A (AQA GCSE Biology): Exam Questions

Which keyword matches the following definition?

Which organ system releases hormones?

Which system is predominantly involved in transporting hormones around the body?

Table 1 below, lists a number of different responses to certain situations.

Table 1

Complete the table by placing a tick (✔) in the box for each condition, that is an example of homeostasis.

Which is not an example of a secondary sex characteristics?

Name the hormones that are produced in the ovaries.

Which hormone is responsible for causing the development of secondary sex characteristics in males?

Define the term "ovulation".

A group of students wanted to investigate gravitropism in bean seedling roots.

Figure 1 shows part of the set-up of their experiment.

Figure 1

This is part of the method they planned to use:

• Measure the length of the root of 5 bean seedlings

• Pin the 5 bean seedlings to a cork mat as shown in Apparatus A

• Place apparatus A in a dark cupboard for 3 days

• After 3 days, measure the length of the root in each seedling and make a drawing of each seedling

The students' teacher told them that their method was incomplete and that they needed to set up a control experiment (Apparatus B) for comparison.

Describe how a suitable control could be set up so that the students could improve their investigation.

Why was it important that the seedlings in the experiment were placed into a dark room?

The students carried out their experiment using 10 bean seedlings split across two sets of apparatus; Apparatus A and Apparatus B (the control).

The results of the student’s investigation are shown in Table 1 below. The table is incomplete.

Complete the table to calculate the mean change in length for the bean seedlings in Apparatus A and Apparatus B.

Table 1

Figure 2 shows the appearance of the seedlings at the end of the 3 days.

Figure 2

A plant hormone, made in the tip of the root, diffuses from the tip into the tissues of the root.

Explain how the hormone causes the appearance of the seedlings in Figure 2. 

You should refer to both seedlings A and B in your answer.

The skin is the largest organ of the human body.

Every 30 minutes, 0.03 g of skin is lost. 

Calculate how many kg of skin is lost by the average human in 365 days.

Write your answer in standard form.

Name the type of cell division that occurs in the skin to replace those cells that are lost.

In the average adult human male, sperm are continually produced in the testicles by a process known as spermatogenesis.

Every second, around 1500 new sperm cells are made.

Calculate how many sperm cells are produced by an average adult male in 365 days.

Write your answer in standard form.

Compare the type of cell division that occurs in the testes with that that occurs in the skin.

Pigs can be farmed intensively for food production.

Intensive farming is just one way in which modern farming techniques are attempting to address food security.

Explain what is meant by the term ‘food security’.

The number of individuals following a plant-only diet has increased rapidly over the last ten years.

Figure 1 shows how the number of internet searches for ‘plant-only diet’ from individuals in the UK compares to the rest of the World.

Figure 1

Calculate the percentage change in the number of individuals from the UK searching for ‘plant-only diet’ on the internet from 2009 to 2019.

Those that follow a plant-only diet cite the impact of intensive animal farming on the environment as one of their main reasons for not consuming animal products, as well as having concerns with how livestock is reared intensively for meat.

Describe some of the advantages and disadvantages of intensive animal farming.

In many places worldwide, there is a lack of food security.

Those that follow a plant-only diet argue that if we all stopped eating meat, there would be less poverty and higher levels of food security for everyone.

Suggest why.

Humans have been selectively breeding animals and plants for many thousands of years.

For example, dogs can be selectively bred so that they produce fur which does not cause allergies in people.

Suggest two other reasons why dogs might be selectively bred.

Dalmatians are a popular breed of dog but due to extensive inbreeding, they are prone to genetic defects.

All pure-bred Dalmatians produce higher-than-normal levels of uric acid due to a gene mutation.

This can lead to the formation of kidney and bladder stones which have to be surgically removed.

Another breed of dog called Pointer dogs do not possess this faulty gene and have normal levels of uric acid.

Cross-breed Dalmatians, which are about 99% Dalmatian and 1% pointer, look and behave like Dalmatians but crucially do not have the gene mutation which leads to high levels of uric acid. 

Explain how selective breeding was used to produce cross-breed Dalmatians that do not suffer from kidney and bladder stones.

The gene mutation in the pure-breed Dalmatian changes one amino acid in a protein involved in regulating levels of uric acid.

Explain how a change in one amino acid in the protein could stop it from functioning normally.

Figure 3 shows a photograph of the Grand Canyon in Yellowstone National Park, USA.

The canyon formed over many millions of years from the erosion and weathering of rock by the Yellowstone river.

Figure 3

Archaeologists found fossils of five different species of animal, A, B, C, D and E at the locations shown in Figure 3.

All five species are now extinct.

Give two reasons why animals become extinct.

Explain why animals E and C in Figure 3 were not alive at the same time.

Give one piece of evidence that scientists could have gathered from the fossils of animal D to suggest that it evolved from animal B.

The fossils of animals B to E in Figure 3 support Darwin’s theory of evolution by natural selection.

Explain how.

Figure 1 shows part of the evolutionary tree for penguins.

Figure 1

What does the evolutionary tree in Figure 1 tell us about the evolution of the Emperor and King penguins in relation to other species of penguin?

What evidence is used by scientists to build an evolutionary tree to show the relatedness of organisms?

Suggest why scientists view evolutionary trees as “a hypothesis of the evolutionary past”.

The intertidal zone is the area along a coast which is underwater at high tide and above water (exposed) when the tide is low.

A group of students on a field trip in Asia wanted to investigate the distribution of two species of seaweed (C. racemosa and C. microphysa) along a rocky shore to establish whether they could live at certain positions. 

Seaweeds are multicellular algae that produce glucose. 

Describe the role that seaweeds play in an ecosystem as producers.

Describe and explain a method that the students could use to investigate the distribution of the two species of seaweed along the rocky shore using a quadrat and a tape measure. 

You should explain how the students would collect valid data.

How could the students alter their method if they wanted to investigate the abundance of each type of seaweed along the coastline by measuring percentage cover?

Another group of students carried out the same investigation the year before.

Their results are shown in Figure 1 below.

Figure 1

Suggest and explain a conclusion that the students could draw from their results using information from Figure 1.