0610 Biology March 2025 Question Paper 42

1 Fig. 1.1 shows the movement of particles through an epithelial cell in the small intestine. P energy R Q membrane of epithelial cell Fig. 1.1

(a) In Fig. 1.1, arrow P represents the diffusion of oxygen molecules.

(i) Describe what is meant by the term diffusion [2]

(ii) State the type of energy needed for diffusion [1]

(b) Carbon dioxide molecules also move by diffusion.

(i) State the name of the process in human cells that produces carbon dioxide [1]

(ii) On Fig. 1.1, draw an arrow to show the direction of diffusion of carbon dioxide molecules.

[1] , ,

(c) In Fig. 1.1, arrow Q represents another type of particle movement.

Identify the type of particle movement represented by arrow Q.

Explain your answer. type of movement explanation [3]

(d) In Fig. 1.1, particle R moves from the lumen of the small intestine into the epithelial cell.

Suggest why particle R cannot be starch [2] , ,

(e) Fig. 1.2 is a photomicrograph of red onion cells. Fig. 1.2

Fig. 1.3 is a photomicrograph of the same red onion cells after being immersed in a salt solution. Fig. 1.3 , ,

Using Fig. 1.2 and Fig. 1.3, describe and explain the difference in appearance of the cells before and after immersion in salt solution [6]

[Total: 16] , ,

2 (a) The internal body temperature of a person was recorded.

Fig. 2.1 shows the results. 35 36 37 38 39 internal body temperature / °C time F Fig. 2.1

(i) Using the information in Fig. 2.1, calculate the temperature range for the internal body temperature of the person.

State the units [1]

(ii) On Fig. 2.1, draw a line to show the set point for the internal body temperature of the person. [1]

(iii) The maintenance of internal body temperature is an example of homeostatic control.

State the name of the mechanism for homeostatic control [1] , ,

(iv) On Fig. 2.1, region F shows a change in body temperature.

Explain how the body causes the change in body temperature shown [5] , ,

(b) Fig. 2.2 shows a cross-section of human skin. E D C capillaries arteriole A B Fig. 2.2

(i) State the letter of the structure shown in Fig. 2.2 that produces sweat [1]

(ii) State the names of structures C and D shown in Fig. 2.2. C D [2]

[Total: 11] , ,

3 (a) Fig. 3.1 shows the percentage of water in different structures of the human body. brain 73% eye 95% heart 75% lung 83% bones 31% blood 94% kidney 79% muscles 75% Fig. 3.1

(i) The mean mass of a human eye is 28 g.

Using information from Fig. 3.1, calculate the mass of water in a human eye.

Give your answer to two significant figures g

[2]

(ii) Describe the importance of water in the human body [3] , ,

(b) Cholera is a disease caused by a pathogen in contaminated water.

Fig. 3.2 is a diagram of the cholera pathogen. M L DNA plasmid Fig. 3.2

(i) State the name of structures L and M shown in Fig. 3.2. L M [2]

(ii) Identify two features shown in Fig. 3.2 that are typical of prokaryotes. 1 2 [2]

(iii) State the type of pathogen that causes cholera [1]

(iv) The scientific name for the pathogen that causes cholera is Vibrio cholerae.

State the genus name for this pathogen [1] , ,

(v) Explain how the cholera pathogen causes dehydration of the human body [3]

(vi) Complete the sentences about the use of plasmids in genetic modification. During genetic modification, human DNA and plasmid DNA are cut with a restriction enzyme. This creates which are joined together using an enzyme called The modified plasmid containing

the human gene is called a plasmid.

[3]

[Total: 17] , ,

4 (a) Fig. 4.1 shows part of a human placenta and umbilical cord. The arrows show the direction of blood flow. to fetus from fetus Fig. 4.1

(i) Describe the functions of the placenta and the umbilical cord shown in Fig. 4.1 [4] , ,

(ii) A fetus develops inside an amniotic sac.

Describe the functions of the amniotic sac and amniotic fluid [3]

(b) Syphilis is a sexually transmitted infection (STI) that can be passed from a mother to her fetus.

(i) State the name of one other STI that can be passed from mother to fetus [1]

(ii) State two ways to control the spread of STIs. 1 2 [2]

[Total: 10] , ,

5 (a) Fig. 5.1 shows a cross-section of a leaf. T Fig. 5.1

(i) On Fig. 5.1, draw a circle around one vascular bundle. [1]

(ii) On Fig. 5.1, draw a label line and the letter X to identify the palisade mesophyll tissue.

[1]

(iii) State the name of the cell structure in palisade mesophyll cells where photosynthesis occurs [1]

(iv) Describe the functions of the tissues in a vascular bundle in a leaf [4] , ,

(b) The leaf shown in Fig. 5.1 is from an aquatic plant adapted to live in water. The leaves float on the surface of the water.

(i) State the term used to describe plants that are adapted to live in water [1]

(ii) Identify feature T shown in Fig. 5.1 and explain how this feature adapts the leaf to float on the surface of the water. feature T explanation [2]

(iii) Explain one other adaptation of this group of aquatic plants [2]

[Total: 12] , ,

6 (a) Microplastics are pieces of plastic with a diameter less than 0.5 cm.

Fig. 6.1 shows the mass of microplastics in the oceans between 2000 and 2040. The data between 2000 and 2020 is an estimate. The data after 2020 is a prediction. 0 2000 2010 2020 2030 2040 0.5 1.0 1.5 2.0 mass of microplastics / million tonnes year Fig. 6.1

(i) Suggest why the mass of microplastics between 2000 and 2020, shown in Fig. 6.1, is an estimate [2]

(ii) Using Fig. 6.1, calculate the predicted percentage increase in the mass of microplastics in the oceans between 2000 and 2040.

Space for working % [2] , ,

(b) Phytoplankton are producers found in the ocean. Phytoplankton absorb microplastics into their cells.

(i) Describe what is meant by the term producer [2]

(ii) Fig. 6.2 shows a shearwater bird.

Shearwater birds feed on fish in the ocean. Fig. 6.2

Suggest how microplastics can end up in consumers such as shearwater birds [2] , ,

(iii) The population of shearwater birds is decreasing.

Describe three ways the population of shearwater birds can be conserved. 1 2 3 [3]

(iv) Explain the risks to a population if its population size decreases [3]

[Total: 14] , ,