Cambridge IGCSE Biology - 0610 - Core Paper 3 2018 Winter Zone 2

The boxes on the left contain the names of processes from the carbon cycle.
The boxes on the right contain some descriptions of processes.
Draw one straight line from each process to link the process to its description.
An example has been done for you.
[Image_1: Matching process and description with lines connecting them]

(a) (i) Explain why the seeds in dishes B and C did not germinate.

Dish B .......................................................................................
.......................................................................................

Dish C .......................................................................................
.......................................................................................

(ii) In a second investigation, maize seeds were placed in a dish containing damp cotton wool.

This dish was left in the dark for five days at 20 °C.

Predict and explain the results.

prediction .......................................................................................
.......................................................................................

explanation .......................................................................................
.......................................................................................


(b) A student gathered 70 maize seeds from plants growing in a field. The seeds were placed in dishes containing damp cotton wool.

After five days only 64 seeds had germinated.

(i) Calculate the percentage of seeds that germinated.

Show your working.
Give your answer to the nearest whole number.

...............................................................%

(ii) Suggest a reason why some of the seeds did not germinate.
.......................................................................................
.......................................................................................
.......................................................................................

This question is about biological molecules.
Choose words or phrases from the list to complete the sentences.
Each word or phrase may be used once, more than once, or not at all.

calcium carbon carbon dioxide carbohydrate
cellulose chloroplasts fat glycerol
glycogen iron methane nitrogen
oxygen protein starch

Fats are composed of the elements .......................................... , hydrogen and .......................................... only. All proteins contain these three elements and the element .......................................... .

Glucose is a type of .......................................... .

Animals store excess glucose as .......................................... in the liver.

Plants store excess glucose as .......................................... . Plants also convert glucose to .......................................... which is used to make cell walls.

(a) Fig. 4.1 shows teeth in a human skull.


Fig. 4.1
Add label lines and labels to Fig. 4.1 to identify an incisor tooth and a molar tooth. [2]

(b) Fig. 4.2 represents the teeth of two adults, D and E. It shows the numbers of the types of teeth and the number of decayed teeth.


Fig. 4.2
A healthy adult human has 32 teeth.

(i) State the number of teeth E has lost.
....................................................................................................... [1]

(ii) State the number of decayed teeth present in D.
....................................................................................................... [1]

(iii) Suggest two reasons why D and E have different numbers of decayed teeth.
1 ......................................................................................................
.......................................................................................................
2 ......................................................................................................
....................................................................................................... [2]

(iv) Identify the type of tooth that decays most frequently in Fig. 4.2.
....................................................................................................... [1]

(c) Describe how bacteria are involved in tooth decay.
.......................................................................................................
.......................................................................................................
.......................................................................................................
....................................................................................................... [2]

(a) Fig. 5.1 shows a diagram of part of the alimentary canal and associated structures.

Fig. 5.1

(i) State the names of the structures labelled H and J.
Write your answers on Fig. 5.1. [2]

(ii) On Fig. 5.1 draw label lines with letters to show:
N where faeces are stored
P where most water is absorbed
R where digested food is absorbed. [3]

(b) (i) State the name of the process that is defined as the movement of digested food molecules into the cells of the body where they are used, becoming part of the cells.
................................................................................................................................................[1]

(ii) State the name of the process that removes faeces from the body.
................................................................................................................................................[1]

(c) Fig. 5.2 shows how the rate of reaction of a digestive enzyme changes with pH.

Fig. 5.2

(i) Describe the effect of the increase in pH on the rate of reaction shown in Fig. 5.2.
................................................................................................................................................
................................................................................................................................................
................................................................................................................................................
................................................................................................................................................[2]

(ii) State one factor other than pH that will affect enzyme activity.
................................................................................................................................................[1]

(a) (i) State the name of cell T in Fig. 6.1.
....................................................................................................................[1]
(ii) State the name of the process that takes place at S to form cell T in Fig. 6.1.
....................................................................................................................[1]
(iii) State where in the human body process S takes place.
....................................................................................................................[1]
[Image_1: sperm cell, egg cell, process S, cell T, ball of cells]

(b) (i) Some humans have the ability to roll their tongues and some cannot roll their tongues.
This characteristic is controlled by genes.
Fig. 6.2 shows two boys: boy A cannot roll his tongue and boy B can roll his tongue.
[Image_2: boy A, boy B]
The allele for tongue rolling (T) is dominant to the allele for non-tongue rolling (t).
Fig. 6.3 shows a family tree for this characteristic. Individual 1 and his partner are both heterozygous for tongue rolling.
[Image_3: Family Tree]
Complete Table 6.1 by inserting the genotypes of the numbered individuals in Fig. 6.3.
[Table_1]
[3]
(ii) Individual 2 in Fig. 6.3 is heterozygous for tongue rolling. He marries a woman who cannot roll her tongue.
State all of the possible genotypes of their children and predict the ratio of phenotypes for their children.
possible offspring genotypes: ..........................................................
ratio of phenotypes: ..............................................................
[2]

(a) Complete the sentences by placing appropriate words in the spaces to give a definition of transpiration.

In transpiration water is lost from the ......................... of a plant.
The water .................................... from the surface of the ................................
cells and water vapour is produced.
The water vapour moves by .................................... out of the plant through pores
called .......................................... .
[5]

(b) Complete Table 7.1 by
• stating \textbf{two} environmental conditions that affect the rate of transpiration
• stating how a \textbf{decrease} in each environmental condition affects the rate of transpiration.

\begin{center}
\textbf{Table 7.1}

\begin{tabular}{|l|l|}
\hline
environmental condition & effect of a decrease on the rate of transpiration \\ \hline
& \\ \hline
& \\ \hline
\end{tabular}
\end{center}
[4]

(a) (i) State the function of a red blood cell.
.....................................................................................................[1]

(a) (ii) State two ways in which a red blood cell is adapted to its function.
1 ......................................................................................................................
..........................................................................................................................
2 ......................................................................................................................
.........................................................................................................................
[2]

(b) State the name of a component of blood that is responsible for clotting.
.........................................................................................................................[1]

(c) (i) State the name of the disease caused by a blockage in the arteries supplying the heart muscle.
.........................................................................................................................[1]

(c) (ii) List three risk factors that increase the risk of a blockage in the arteries supplying the heart muscle.
1 ..........................................................................................................................
2 ..........................................................................................................................
3 ..........................................................................................................................
[3]

(d) Fig. 8.2 is a diagram of the circulatory system. The blood vessels are labelled with letters.

Complete Table 8.1 by identifying the letter of the named blood vessels in Fig. 8.2.
[Table_1]
{"name of blood vessel": "letter", "aorta": "", "pulmonary artery": "", "renal vein": "", "vena cava": ""}
[4]

(e) Describe how the structures of the circulatory system maintain a one-way flow of blood.
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
.................................................................................................................................
[4]

(a) Some animals are farmed intensively.
Describe the negative impacts to an ecosystem of intensive livestock production.
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
..................................................................................................................................................
................................................................................................................................. [4]

(b) State why fertilisers, herbicides and insecticides are used in farming.
fertilisers .......................................................................................................................................
..................................................................................................................................................
herbicides .......................................................................................................................................
..................................................................................................................................................
insecticides .......................................................................................................................................
.................................................................................................................................................. [3]

(c) Fertilisers, herbicides and insecticides can all pollute water.
List two other sources of water pollution.
1 ..............................................................................................................................................
2 .............................................................................................................................................. [2]