2E Animal Nutrition

Time: 1 hour 30 minutes

Total marks available: 90

Total marks achieved:

Q1.

Complex carbohydrates are broken down in the human digestive system.

(a) Name the elements present in a carbohydrate molecule.

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(b) Starch and glucose are carbohydrates found in living organisms.

Complete the table to show some of the properties of starch and glucose. Insert a tick if the property applies or a cross if it does not.

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(5)

(c) (i) Describe how you could test for the presence of glucose in a substance.

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(ii) Give two safety precautions you would take when carrying out the test.

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(3)

(2)

(Total for question = 11 marks)

Q2.

Read the passage below. Use the information in the passage and your own knowledge to answer the questions that follow.

(a) Suggest how spending time outdoors can reduce the chance of getting rickets (lines 7 and 8)...........................................................................................................................................................................................................................................................................................................................................................................................................................................

(b) Suggest why vitamin D deficiency is more of a problem for children than for adults.

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(c) Vitamins are an essential part of a balanced diet. Give three other components of a balanced diet.

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(d) Suggest why snacking on crisps, chocolate and soft drinks is an unsuitable diet for children who are not very active (lines 16 and 17).

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(e) Suggest the health problems that might develop if children have too much fat in their diet (line 18).

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(f ) Describe how you would carry out an experiment to find out the energy value of a potato crisp.

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Q3.

The Bristol scale is used to classify human faeces. It is used to help diagnose patients who have problems with their alimentary canal.

(a) Suggest why a patient might produce Type 1 faeces.

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(b) Suggest why a patient might produce Type 7 faeces.

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(c) Describe how food is moved through the gut.

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(d) Name the part of the gut where faeces are(i) stored

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(ii) expelled

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(e) Explain how egestion differs from excretion.

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(1)

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(Total for question = 10 marks)

Q4.

The table shows the percentage of protein, fat and minerals found in the same mass of meat from different animals.

(a) (i) Which meat contains the least protein?

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(ii) Calculate how many grams of protein are present in one kilogram of rabbit meat. Show your working.

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Answer ........................................................... g

(b) Which type of meat would provide the most energy?

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(c) Give two uses of fat in the human body.

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(d) Name the mineral in meat that is needed to make haemoglobin.

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(2)

(1)

(Total for question = 7 marks)= 11 marks)

Q5.

The diagram shows the label on a packet of a new kind of food for people who want to lose weight.

The food is a powder which is added to water to make a liquid drink. The label on the packet claims that the food provides a complete balanced diet.

(a) What is meant by the term balanced diet?

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(b) A pregnant woman decides that this food does not provide her with a complete balanced diet.

Use the information on the packet to give two reasons why the pregnant woman may be right.

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(2)

(2)

(Total for question = 4 marks)

Q1.

This question was on carbohydrates. All but a very few candidates could give the elements present in a carbohydrate molecule in part a). However, only the best candidates gained full credit in part b) for completing the table on the properties of starch and glucose. In part c) most candidates were able to describe a test they could carry out for glucose. A number of responses included adding glucose to the substance to be tested. Most responses also gave two safety precautions such as heating in a water bath and wearing safety glasses.

Q2.

The comprehension was about diet in children and tested understanding of vitamins, balanced diet and energy balance. In part (a), most appreciated that spending time outdoors allows sunlight to make vitamin D and so reduce the chance of getting rickets. Those who thought sunlight contains vitamin D were not credited. Part (b) was more challenging, but about 60% appreciated that children are still growing which is why a vitamin D deficiency would cause a problem, particularly with bone development. Those who did not read the question carefully wrote about the time children spend indoors or commented on the amount of cod liver oil they take. Most candidates were able to list three other components of a balanced diet in part (c). In part (d), a pleasing number of candidates appreciated the energy balance implications of eating foods rich in carbohydrates and fats and not using the calories due to hypoactivity. Then, in part (e), many were aware of the health risks of a high fat diet in causing obesity, cardiovascular disease and diabetes. Part (f) required candidates to write about a practical procedure listed in the specification. Those who had carried out the practical were able to recall many of the points allowed in the mark scheme. However, it was clear that some candidates had no idea what was required to find out the energy value of a food sample.

Q3.

This question provided students with a copy of the Bristol scale used to diagnose problems with alimentary canal function. In parts (a) and (b) the more able candidates were able to suggest why the different form of faeces might be produced. In part (c) the question required candidates to describe how food is moved through the gut. Most responses gained some marks with the best responses describing peristalsis as contraction of the circular and longitudinal muscles in the gut wall. In (d) most candidates could name the part where faeces are expelled but fewer could name the part where faeces are stored. In part (e) candidates needed to explain how egestion differs from excretion. Very few seemed to understand the differences and only the best candidates scored full marks. Many responses talked about faeces being excreted and few candidates knew what egestion was.

Q4.

This question presented data on the protein, fat and mineral content of 5 different meats. In part a) almost every candidate could correctly identify the meat with least protein and calculate how many grams would be present in one kilogram of rabbit meat.

Q5.

The question gave a picture of a water plant growing on a lake. In (a), most candidates were able to suggest a mineral ion required by a plant and its role in

the plant. We would expect candidates to give the ions required in the specification - magnesium for chlorophyll or nitrate for amino acids. However, other ions were also credited. Candidates then had to plot a line graph of some experimental results in (b). Those from centres who had practiced graph plotting scored very well. In (d), many candidates could identify three variables to be kept constant with light intensity, carbon dioxide level and temperature being the most common correct answers.

Q6.

(a) required a description of how the leaf is adapted to absorbcarbon dioxide. Many candidates gained full credit for writing about the presence of a large surfaces area and many stomata. The thinness of the leaf provides a short diffusion distance and the moist surfaces of the spongy mesophyll cells. In(b) candidates had to write a balanced chemical equation for photosynthesis. Although many gained full marks some confused respiration, others gave wrong formulae. In part (c) students needed to remember the practical experiment used to show that light is required for photosynthesis. This is straight from the specification and we were disappointed by how many candidates did not know how to destarch a leaf or test one for starch.

Q7.

This question gave candidates a photograph of a variegated leaf. In (a) almost all could describe the role of chloroplasts. Again, In part (b), most couldname the structures in the diagram of the plant cell. The experiment described in part (c) should have been familiar to all candidates. However this item (iv) discriminated well between candidates and only the best could identify the appearance of the leaves after testing for starch. In parts (ii) and (iii) those candidates who had carried out investigations testing leaves for starch could answer well and those who had not seen this practical performed poorly. In part (iv) almost all could correctly identify iodine solution as the chemical test for starch.

Q8.

This question provided a diagram of a section through a leaf. In part a) almost all candidates could correctly name the structures labelled. Most were able to give the function of the waxy cuticle as reducing transpiration and preventing entry of microorganisms. Most could also give the word equation for photosynthesis, although a significant minority chose to give chemical formulae. In the final part the better candidates gained full credit for explaining that oxygen exits the stomata down a diffusion gradient from a high concentration to a lower one outside the leaf. Part b) asked candidates to suggest reasons why some plants lose their leaves in cooler months. Answers that gained credit included reduction of water loss, lack of sunlight for photosynthesis and conservation of energy resources.

Q9.

This question required students to use information from a label on a slimming drink. In part (a) most students gained some credit with the best answers describing a balanced diet as containing the correct proportions of carbohydrate, protein, lipid, vitamins and minerals. In part (b) most could identify why the drink would not be suitable for a pregnant woman.

Q1.

Q2.

Question number Answer Notes Marks

(a) sun/ light makes vitamin D; 1

(b) children still growing (bones) Ideveloping(bones) / eq;

allow converse -adult bones fully developed ignore ref to cod liver oil / timespent indoors

1

(c) fat / lipid;carb ohydrate; protein;fibre I roughage;water;minerals / salts / ions;

only accept generic names, so iron = O, glucose = O

if list ignore non gene ric names

Max 3

(d) 1 , idea of high in sugar / fat /carbohydrate I energy I calories

2. not used / not burnt / not neededI eq;

marks are for idea of energy balanceand not consequence

2

{e) 1 , obesity / overweight / jointdamage;

2. diabetes;

3. heart disease I heart attack / angina I

cardiac arrest / eq;

4. blocks/ narro ws/ build up arteries

ignore vein / capillary

Max 2

Iblocks blood vessels / high blood

pressure;

5. stroke;

{f) 1 , weigh crisp / mass of crisp;2. burn crisp / eq;

3. burnt completely I eq;

4. heat water /hold ! burning crisp) under tube / hold burning crisp) under water / calorimeter / eq;

5. volumeof water / mass of water;

6. measure temperature before and after I

temperature rise I temperature increase I

change in temperature / eq;

allow marks ifclear in formula

allow heat water if implicit

Max 4

Tota l 13 marks

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Q5.