Cambridge IGCSE Biology - 0610 - Core Paper 3 2016 Winter Zone 3

Fig. 1.1 shows five different vertebrates.

(a) State one feature that is shared by all vertebrates.
.......................................................[1]
(b) The five animals in Fig. 1.1 all belong to the same group of vertebrates.
(i) State the name of this group of vertebrates.
.......................................................[1]
(ii) State two features which place the five vertebrates in this group.
1 .......................................................
2 .......................................................[2]

Fig. 2.1 is a drawing of a piece of plant tissue.


(a) (i) What name is given to this type of tissue? Choose your answer from the list.
palisade mesophyll  root hair  xylem
.......................................................................................................................[1]
(ii) Name the part labelled A in Fig. 2.1.
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(b) This tissue is important for both transport and support in the plant.
Explain how the structure of this tissue allows it to perform these functions:
transport ........................................................................................................
........................................................................................................................
support ...........................................................................................................
........................................................................................................................[2]

(c) The cells in this tissue do not contain some of the structures found in most plant cells.
State one structure that is missing from the tissue shown in Fig. 2.1.
.......................................................................................................................[1]

Doctors can use an ECG machine to monitor a patient’s heart rate. Fig. 3.1 shows the ECG of a healthy man.

(a) Use Fig. 3.1 to calculate the man’s heart rate. Give your answer in beats per minute. Show your working.
.............................. beats per minute [2]

(b) The heart rate can also be measured by listening to the sounds that the heart makes. State what causes the sounds made by the heart.
.......................................................... [1]

(c) Several things can alter a person’s resting heart rate. Fig. 3.2 shows a normal resting ECG and the resting ECG of a person with a heart problem.

(i) Describe how this heart problem affects the person’s resting heart rate. Use data from Fig. 3.2 to support your answer.
.......................................................... [2]

(ii) State one factor which can alter the heart rate of a healthy person to produce the same effect as the heart problem shown in Fig. 3.2.
.......................................................... [1]

(d) Describe the meaning of the term coronary heart disease and state one factor that increases the risk of developing coronary heart disease.
description ..........................................................
risk factor .......................................................... [2]

(a) Define the term photosynthesis and outline one reason why it is important to ecosystems.
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(b) (i) Name the green substance that plants need for photosynthesis.
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(ii) Name the gas that plants need for photosynthesis.
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(iii) Name the gas that plants produce during photosynthesis.
...................................................................................................................... [1]

(c) Fig. 4.1 shows the apparatus a student used to investigate how light intensity affects photosynthesis.

The student placed an aquatic plant under a funnel in a beaker of water. During the investigation she placed the lamp at different distances from the aquatic plant. At each distance she counted how many bubbles the aquatic plant produced in one minute. The bubbles of gas were then collected in the test-tube.

Fig. 4.2 shows the results of her investigation.

(i) Use Fig. 4.2 to find the number of bubbles produced when the lamp was placed 10 cm from the aquatic plant.
............................. bubbles per minute [1]

(ii) Describe how the rate of photosynthesis is affected by the distance of the lamp from the aquatic plant.
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(iii) Predict the number of bubbles that would be produced if the lamp was placed 21 cm from the aquatic plant.
............................. bubbles per minute [1]

(d) Another student placed the lamp 15 cm from the aquatic plant and kept it there. Although the light intensity stayed the same, the number of bubbles produced by the aquatic plant per minute decreased. Suggest an explanation for this.
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This question is about the movement of substances into and out of cells.
(a) Draw one straight line from each box on the left to join it with the box containing the correct description on the right.
[Image_1: how substances pass into and out of cells and descriptions]

(b) (i) The contents of a meal must be digested before they can be absorbed.
State the two types of digestion.
1 ..............................................................
2 ..............................................................
[1]
(ii) The body uses enzymes to digest food.
Define the term enzyme.
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..............................................................
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[2]
(iii) Give one example of a digestive enzyme and the substrate it acts on.
enzyme ..............................................................
substrate ..............................................................
[1]
(iv) Suggest why the human digestive system must make many different enzymes.
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[2]

Reflex actions play an important part in human behaviour.

(a) (i) What is meant by the term \textit{reflex action}?
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........................................................................................................................[2]

(ii) Suggest why reflex actions are important.
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(b) A reflex arc is made up of a number of different parts. Complete the sentences that describe a reflex arc by writing the correct words in the spaces.
Each word may be used once, more than once or not at all.

brain effector motor neurone receptors relay neurone sensory neurone

Changes in the surroundings are detected by ...................................................... which generate an impulse in a ........................................................ . Nerve impulses travel from this cell to a ........................................................ . The impulses then travel to a ........................................................ . Finally the nerve impulse is passed to an ...................................................... which results in the body responding to the changes. [4]

(c) Fig. 6.1 is a diagram of a reflex arc.
It shows two different neurones.
These are labelled neurone A and neurone B.
not drawn to scale
Fig. 6.1

(i) There are small gaps at the junctions between neurone A and neurone B.
State the name of these gaps.
........................................................................................................................[1]

(ii) State where in the body neurone B can be found.
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(a) For over 300 years sailors hunted the slow-moving giant tortoises as a source of food.
They also left goats on the islands to provide food for sailors to eat in the future.
Giant tortoises and goats are both herbivores.
Use this information to suggest and explain two reasons why giant tortoises became an endangered species.
1 ........................................................................................................................
...........................................................................................................................
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2 ...........................................................................................................................
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[4]
(b) Outline two ways that an endangered species can be conserved.
1 ...........................................................................................................................
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2 ...........................................................................................................................
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[2]
(c) The loss of one species can affect other organisms living in the same environment.
Suggest how the loss of one species of secondary consumer from a food web might affect other organisms in the same food web.
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(a) A farmer buys a packet of seeds that produce plants with purple beans. The packet states that the seeds are homozygous for bean colour. Define the term homozygous. ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ [2]

(b) The farmer plants the seeds and the bean plants grow. When the beans are harvested the farmer notices that most of the beans are purple but a few beans are green. He decides that some of the plants carried the allele for the green coloured bean and that this allele is recessive.
(i) Define the term allele. ............................................................................................................................................................................ ............................................................................................................................................................................ [1]
(ii) Suggest why the farmer decided that the allele for green coloured beans is recessive. ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ [2]

(c) Describe the difference between the genotype and the phenotype of an organism. ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ [2]

(d) The farmer only wants large purple beans so he crosses the plants that produce the largest purple beans and does this for several generations. He does not breed from any plant that produces small or green beans. Eventually all his plants produce only large purple beans. What is this process called? ............................................................................................................................................................................ [1]

(e) Genetic engineering has been used to provide more food for the increasing human population. Give an example of genetic engineering in a crop plant and state how this will produce more food. ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ ............................................................................................................................................................................ [2]

This question is about human nutrition.
The three boxes on the left contain definitions of processes involved in human nutrition.
The four boxes on the right contain the names of some of these processes.
(a) Draw one straight line from each definition to join it to the correct process.

definition                               process
[Box 1: the movement of digested food molecules into the cells of the body where they are used, becoming part of these cells]          absorption
[Box 2: the passing out of food that has not been digested or absorbed, as faeces, through the anus]          assimilation
[Box 3: the taking of substances, e.g. food and drink, into the body through the mouth]          egestion
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           >ingestion


(b) Fig. 9.1 shows the teeth in the upper jaw of an adult human.
[Image: fig_9_1] Fig. 9.1
(i) On Fig. 9.1 label with a letter X one tooth that is adapted for cutting food.
State the name of the type of tooth adapted for cutting.
......................................................................................................................................................... [2]
(ii) On Fig. 9.1 label with a letter Y one tooth adapted for chewing food.
State the name of the type of tooth adapted for chewing.
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(c) Fig. 9.2 shows a section through a human tooth.
[Image: fig_9_2] Fig. 9.2
Two of the layers of the tooth are labelled A and B.
Eating too much sugar can be the beginning of a process that ends in dental decay.
Explain how sugar is involved in decay and how decay affects parts A and B.
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........................................................................................................................................................ [3]

Fig. 10.1 shows the energy flow in a simple food chain.
For every 200J of energy in the cabbage eaten by the caterpillar 35J passes into the bird.
(a) Calculate the percentage of energy that is transferred from the cabbage to the bird in this food chain.
Show your working. .......................................................... % [2]
(b) (i) The caterpillar passes 35J of energy from the cabbage to the bird.
The rest of the 200J is lost in the form of respiration and faeces.
Use this information to find the energy the caterpillar loses in respiration.
Show your working. .......................................................... J [2]
(ii) Suggest one other way the caterpillar uses the energy during its lifetime. .................................................................................................................. [1]