Pathogens

Malaria is a disease that causes damage to the blood and liver.

Which type of pathogen causes malaria?

State how the pathogen that causes malaria is spread.

Measles is a disease caused by a virus.

Figure 9 shows the number of measles cases reported in England and Wales from 1985 to 2015.

Explain one conclusion that can be made about the change in the number of measles cases reported from 1985 to 2015.

Describe two ways the immune system will respond to an infection by a pathogen.

Beriberi is a disease caused by a lack of vitamin B1 in the diet.

Give one reason why beriberi is classed as a non‑communicable disease.

*(ii) Beriberi can affect reflexes.

Figure 10 shows a reflex arc.

When the skin is pricked by a pin, electrical impulses travel through a reflex arc.

Describe the path taken by electrical impulses from the skin to the muscles in the arm.

Include the names of neurones X, Y and Z in your answer.

Figure 10 shows colonies of bacteria growing on an agar plate.

Each colony starts as one bacterium.

Every time bacteria reproduce, the number of bacteria in each colony doubles.

Calculate the number of bacteria in a colony after five hours, if each bacterium reproduces every 30 minutes.

_........ bacteria

Some bacteria are pathogens.

State the meaning of the term pathogen.

Explain why antibiotics can be used to treat bacterial infections.

A rod-shaped bacterium is 0.005 mm long.

A student draws the rod-shaped bacterium.

The bacterium in the drawing is 80 mm long.

Calculate the magnification of this drawing.

magnification =_........

* (c) Figure 11 shows a bacterial cell and a plant cell.

Describe the similarities and differences of a bacterial cell and a plant cell.

Figure 2 shows colonies of bacteria growing on an agar plate.

Each colony starts as one bacterium.

Every time bacteria reproduce, the number of bacteria in each colony doubles.

Calculate the number of bacteria in a colony after five hours, if each bacterium reproduces every 30 minutes.

_........ bacteria

Some bacteria are pathogens.

State the meaning of the term pathogen.

Explain why antibiotics can be used to treat bacterial infections.

A rod-shaped bacterium is 0.005 mm long.

A student draws the rod-shaped bacterium.

The bacterium in the drawing is 80 mm long.

Calculate the magnification of this drawing.

magnification =_........

Some bacteria cause disease.

Which word describes an organism that causes disease?

Draw one straight line from each disease to the main way that the disease is spread.

disease main way the

A scientist investigated the effect of temperature on the growth of bacteria.

The bacteria were grown at 10 °C and 20 °C.

The number of bacteria grown at each temperature were counted every two hours.

Figure 1 shows the result.

Figure 2 shows a graph of the results at 20 °C.

Plot the points on the graph for the number of bacteria at 10 °C.

The first two points have been plotted for you.

Draw a line of best fit on the graph for 10 °C.

Describe how the growth of bacteria at 10 °C was different from the growth of bacteria at 20 °C.

Measles is a communicable disease caused by a virus.

What can a virus also be classified as?

Give one reason why measles is described as a communicable disease.

The human immunodeficiency virus (HIV) can cause AIDS.

Which type of cell is destroyed by the HIV virus?

Describe how the specific immune system defends the body against disease.

Figure 7 shows the number of people per million of the population in five European countries who were diagnosed with measles in one year.

The population of Belgium in that year was 11.18 million.

Calculate the number of people in Belgium diagnosed with measles.

Give your answer to three significant figures.

_........ people

Countries do not report the total number of people diagnosed with measles. Countries report the number of people diagnosed with measles per million of the population.

Give one reason why this is better.

Give one reason why the number of people per million diagnosed with measles is different in these countries.