Transport Systems in Animals (SQA National 5 Biology): Exam Questions

Three students carried out an investigation into the effect of exercise on heart rate.

Each student measured their heart rate after completing the same exercises.

After each student’s heart rate returned to its resting rate, they repeated the investigation.

Which of the following would improve the reliability of the results?

The results of a blood count for two patients are shown.

(i) Which patient has all four components within the normal range?

[1]

Patient................................

(ii) Four weeks later, both patients had their blood re-tested.

The haemoglobin content of the blood of Patient S had increased by 20%.

Calculate the number of units of haemoglobin in this second blood count.

[1]

....................................units

Other than containing haemoglobin, describe one way in which a red blood cell is specialised to carry out its function and explain the advantage of this specialisation.

Description.....................................................................................................

Explanation.....................................................................................................

Two types of blood vessel are arteries and veins.

Compare the structure of these two types of blood vessel.

Haemoglobin’s ability to bind to oxygen is affected by the pH of the blood.

The table shows the percentage of haemoglobin bound to oxygen at different pH levels.

The percentage of haemoglobin bound to oxygen when the pH of blood is 7.1 is likely to be

Coronavirus is a pathogen, which causes COVID‑19. Most people with COVID‑19 feel better within a few days or weeks of their first symptoms. Long COVID can be diagnosed when symptoms last longer.

Symptoms of long COVID include extreme breathlessness, memory and concentration issues. In some cases, other organs can also be affected causing other health issues.

A study monitored changes in the health of 500 patients with long COVID.

Between the start and the end of the study, the percentage of patients with extreme breathlessness decreased from 38% to 30%, those with memory and concentration issues decreased from 48% to 38%, and those with other health issues decreased from 57% to 45%.

At the end of the study, 10% had no organs affected, 65% of patients had only one organ affected and 25% had multiple organs affected.

Name the type of white blood cell that produces antibodies against coronavirus.

Using information from the passage, complete the table by adding:

(i) a column heading

[1]

(ii) the relevant data.

[1]

Calculate the simple whole number ratio of the percentage of long COVID patients who had multiple organs affected, to those with one organ affected, to those with no organs affected.

.......................................... : ...................................... : .....................................
multiple organs affected one organ affected no organs affected

Suggest a reason why the study could be considered invalid.

The diagram represents part of the circulatory system in humans.

(i) Name the heart chamber labelled M.

[1]

(ii) Compare the carbon dioxide concentrations in the blood travelling through blood vessels L and N.

[1]

The heart is composed of muscle tissue that requires its own blood supply.

(i) Name the blood vessel that supplies the heart tissue with blood.

[1]

(ii) Explain why the heart muscle cells will stop contracting if this blood vessel becomes blocked.

[2]

Which row in the table describes some features of veins?

Three students carried out an investigation into the effect of exercise on heart rate.

Each student measured their heart rate after completing the same exercises.

After each student’s heart rate returned to its resting rate, they repeated the process.

Which of the following would increase the reliability of the results?

High altitude training is an important part of athlete preparation for endurance sports such as long‑distance running.

As altitude increases the oxygen concentration of the air decreases.

The table shows the effect of training at different altitudes on athletes’ red blood cell count.

(i) On the grid complete the vertical axis and plot a line graph to show the effect of altitude on average red blood cell count.

[2]

(ii) Describe the relationship between altitude and red blood cell count.

[1]

(iii) Using information from the table, predict the average red blood cell count of an athlete training at an altitude of 3.0 km.

[1]

..............................................million/ml of blood

Red blood cells are important for transporting oxygen.

(i) In what form is oxygen transported by red blood cells?

[1]

(ii) Give one structural feature of a red blood cell that allows it to carry out its function efficiently.

[1]

The human body can be defended against disease by:

The diagram represents the human heart.

Starting where oxygenated blood first enters the heart, identify the order of blood flow through the heart.

A heart attack can be caused by a blockage to a blood vessel that supplies the heart tissue with oxygen.

In which blood vessel does this blockage occur?

The diagrams represent cross sections of three types of blood vessel.

Which row in the table identifies the blood vessels shown in the diagrams?

Measles in the UK

Measles is a disease that can be prevented through two doses of the MMR vaccine. The target set by health experts to achieve measles-free status is to have at least 95% of the population vaccinated. The World Health Organization declared the UK measles-free in 2016.

However, since 2016, cases of measles in the UK have been increasing, with too few people being vaccinated. It was suggested by experts that when measles cases became less common, some people believed that the threat of the disease was less. Another factor was the publication in the late 1990s of a controversial, and since discredited, piece of research wrongly linking the MMR vaccine with autism.

In 2018, there was a marked increase in reported cases, with 994 cases in England and Wales, compared with 284 cases in 2017. There were 307 cases across the UK during the first three months of 2019. In 2019, only 87% of the population in England received their second dose of MMR. In both Wales and Scotland it was 92%, and in Northern Ireland it was 91%.

Measles is caused by a pathogen.

State the meaning of the term ‘pathogen’.

(i) Describe the relationship between the uptake of the vaccine and the number of cases of measles.

[1]

(ii) Suggest a reason why the uptake of the vaccine in the UK has been lower since 2016.

[1]

Calculate the simplest, whole number ratio, of measles cases in England and Wales in 2017 to 2018.

...................... : ........................ cases
2017 2018

Using data from the passage, explain why Scotland lost its measles-free status in 2019.