PHS Edexcel Triple Biology paper 2 HIGHER (sample 2)

Climacteric fruits are fruits that can ripen after they have been removed from the plant.
Which plant hormone can be used to ripen climacteric fruit?

• auxin
• ethene
• gibberellin
• insulin

When climacteric fruits ripen, they release a gas during respiration.
Which gas is released by these fruits during respiration?

• carbon dioxide
• carbon monoxide
• oxygen
• nitrogen

A student investigated how temperature affects the decomposition of climacteric fruit.

The student placed a plastic box containing a banana in a water bath at 20 °C.

The student recorded the time taken for the banana to turn completely black.

This investigation was repeated at 30 °C and 40 °C.

State all the factors the student would need to control to ensure only the temperature affected the rate of decomposition of the banana.

• size of banana

• age / ripeness of bananas

• size of box

• humidity of box

Explain why temperature affects the rate of decomposition.

• microorganisms reproduce faster at higher temperatures, so there is more breakdown of large molecules into smaller
  molecules
• microorganisms die at higher termperatures, causing more breakdown of molecules.
• Enzymes become denatured at lower temperatures, reducing the rate of decomposition.
• Microorganisms encourage the breakdown of smaller molecules into larger molecules at higher temperatures.

A student investigated the distribution of poppy plants in a park.

The student placed a 1 m² quadrat at 10 metre intervals between two points and recorded the number of poppy plants in each quadrat.

Name the technique the student used to study the distribution of poppy plants.

• belt transect

• sampling

• quadrat

• pooting

The table shows the number of poppy plants at 10 metre intervals from point A to point B. Point A is on the edge of some woodland.

Explain the effect of the woodland on the distribution of poppy plants.

• The number of poppy plants decreases (closer to the woodland) and trees block light, light is needed for photosynthesis

• The number of poppy plants increases the closer to the woodland, due to the amount of nutrients provided by the trees.

• The trees block light, which is needed for respiration, decreasing the number of poppy plants.

• The number of poppy plants increases (closer to the woodland) and trees block light, light is needed for photosynthesis

How could you use a quadrat to estimate the number of poppy plants in a field.

• randomly place the quadrat several times,

  record the average number of poppy plants in each quadrat,

  multiply by how many quadrats fit in the field.

• place the quadrat on the field, record the number of poppy plants in each quadrat, multiply the number by the size of the field.

• count all the poppies along one side of the field and multiply by the number up one edge of the field.

• randomly place the quadrat several times,

  record the average number of daisy plants in each quadrat,

  multiply by how many quadrats fit in the field.

A park contains an area of woodland. The woodland is a protected conservation area.
Explain why this woodland increases the biodiversity of the park.

• woodland provides a different type of habitat, which allows different animal or plant species to live in the park
• woodland allows certain species to compete better than others, increasing the numbers of that species.
• woodland decreases the amount of light, resulting in more animals and increasing biodiversity.
• woodland increases the amount of light available, causing more plant growth and increased biodiversity.

A peak flow meter is used to measure the rate at which air is blown out of the lungs. People with asthma can have a reduced peak flow. A student investigated the peak flow of five people with asthma and five people without asthma.

The mean peak flow for people without asthma was 630 dm³ per minute.

The mean peak flow for people with asthma was 480 dm³ per minute.

Use the mean peak flow values to calculate the percentage decrease in peak flow for the people with asthma.

• 24%

• 14%

• 150%

• 0.24%

Explain the effect of reduced airflow in the lungs on aerobic respiration.

• less aerobic respiration, because there is reduced oxygen entering the lungs, which reduces oxygen supplied to the blood

• less anaerobic respiration, because there is reduced oxygen entering the lungs, which reduces oxygen supplied to the blood

• increased aerobic respiration, because there is increased oxygen entering the lungs, which reduces oxygen supplied to the blood

• less aerobic respiration, because there is increased oxygen entering the lungs, which increases oxygen supplied to the blood