AGRICULTURAL SCIENCES
PAPER 1
GRADE 12 
NSC PAST PAPERS AND MEMOS
FEBRUARY/MARCH 2017

MEMORANDUM

SECTION A
QUESTION 1 
1.1

1.1.1 A ✔✔ 
1.1.2 C ✔✔ 
1.1.3 A/B ✔✔ 
1.1.4 B ✔✔ 
1.1.5 B ✔✔ 
1.1.6 C ✔✔ 
1.1.7 D ✔✔ 
1.1.8 D ✔✔ 
1.1.9 C ✔✔ 
1.1.10 A ✔✔ (10 x 2) (20) 

1.2

1.2.1 Both A and B ✔✔ 
1.2.2 B only ✔✔ 
1.2.3 None ✔✔ 
1.2.4 B only ✔✔ 
1.2.5 A only ✔✔ (5 x 2) (10) 

1.3

1.3.1 Amylase/ptyalin ✔✔ 
1.3.2 Commercial farmer ✔✔ 
1.3.3 Superovulation ✔✔ 
1.3.4 Ejaculation ✔✔ 
1.3.5 Courtship ✔✔ (5 x 2) (10) 

1.4

1.4.1 Cardiac ✔ 
1.4.2 Deep litter ✔ 
1.4.3 Dry ✔
1.4.4 Cloning/nuclear transfer✔ 
1.4.5 Ovum/egg/female/reproductive sex cell/gamete✔ (5 x 1) (5) 

TOTAL SECTION A: 45

SECTION B 
QUESTION 2: ANIMAL NUTRITION 
2.1 A representation of the alimentary canal of a farm animal. 

2.1.1 Farm animal represented by the alimentary canal  
Pig ✔ (1)
2.1.2 Importance of parts A and C 
A –
Assists in chemical digestion of food✔ (1) 
C – Assists in chemical digestion and absorption of food✔ (1) 
2.1.3 Explanation of mechanical digestion  

    • Breaking down of the complex food particles into smaller,  simpler particles ✔
    • through physical objects/teeth ✔ (2)

2.2 The absorption of nutrients from the small intestines 

2.2.1 Identification of transport  
A –
Active absorption/carrier molecule theory ✔ (1) 
B – Passive absorption/osmosis/diffusion ✔ (1) 
2.2.2 Reason  
Active absorption 

    • Nutrients move from a lower concentrated area to a higher  concentrated area/against the concentration gradient through  an energy carrier (ATP) ✔ 

Passive absorption 

    • Nutrients move from a higher concentrated area to a lower  concentrated area/along the concentration gradient ✔ (2) 

2.2.3 Identification of the structure labelled C 
Differential permeable/partially/semi-permeable membrane ✔ (1) 
2.2.4 Nutrient absorbed through 

    1. Blood capillaries – Digested protein/carbohydrates/  amino acids /glucose/vitamins/minerals ✔ (1)
    2. Lacteal – Digested fats/glycerol and fatty acids ✔ (1) 

2.3 The various feed components of a ration  

2.3.1 Example of an energy rich concentrate 
Maize meal ✔ (1) 
2.3.2 Feed supplement acting as a source of energy in licks 
Molasses ✔ (1)
2.3.3 Suitability of urea for pigs 

    • Not suitable ✔
      Reason 
    • It cannot be digested by pigs/pigs are monogastric/only  ruminant animals can utilise ✔ (2) 

2.3.4 Tabulation of rations 

SOURCE OF PROTEIN 

EXAMPLE

Natural protein 

Lucerne hay ✔

NPN protein 

Urea ✔

 Table ✔ (3)
2.4 Fodder flow programme  

 

2.4.1 Completion of the table 

    1. 600 x 120 = 72 000 ✔ = 72 tons ✔ 
                            1000 
    2. 200 x 120 = 24 000 ✔ = 24 tons ✔ 
                           1000                                      (4) 

2.4.2 Determining the average cost to feed ONE animal for ONE day

    • R114 277,80 ÷ 113 animals ✔
    • = R1011,31 ÷ 120 days ✔
    • = R8,43 ✔
      OR 
    • R114 277,80 ÷ 120 days ✔
    • = R952,32 ÷ 113 animals ✔
    • = R8,43 ✔ (3)

2.5 Composition of two animal feeds 
2.5.1 Calculating nutritive ration (NR) of FEED B 

  • NR = 1: % digestible non-nitrogen nutrients ✔ 
                           % digestible protein 
  • = 1: 58 ✔ 
           12 
     NR = 1: 4,831:5 ✔ 
    OR 
  • NR = TDN-DP ✔ 
                 DP  
  • = 1 : 70% – 12% ✔ 
                  12%  
  • NR = 1: 4,83/1:5 ✔ (3) 

2.5.2 Justification for not recommending feed A 

  • Wide nutritive ratio ✔ 
  • It has more carbohydrates and fats than proteins/fewer  proteins than carbohydrates and fats ✔ (2)

2.6 Pearson square method  
Calculating Pearson square 
OAT TABLE
Ratio of oats : sunflower is 24:5 ✔ (4)

[35] 

QUESTION 3: ANIMAL PRODUCTION, PROTECTION AND CONTROL 
3.1 Scenario on the optimising of production
3.1.1 Natural resources 

  • Lower production outputs ✔ due to animals fending for  themselves ( 2) 

3.1.2 Feeding  

  • Enough feed (pastures) ✔ will lead to good production✔  
    OR
  • Less feed (pastures) ✔ will lead to poor production. ✔ ( 2)

3.1.3 Exploitative practices  

  • Where the natural balance/equilibrium is disturbed ✔/due to  poor veld management ✔ 
  • Utilise the natural resources to such an extent that it is  permanently damaged ✔and impossible to recover✔
  • More is taken out and nothing is put back in return ✔ 
  • Maximum production no matter what the cost ✔ 
  • Deliberate actions to damage the environment ✔ (Any 2) (6)

3.2 Management practices conducted on piglets  
3.2.1 Identification of management practices 
A – Injection/inoculation/vaccination ✔ (1) 
B –Tail docking ✔ (1) 
3.2.2 Reason for the management practices 
A – To administer iron/Fe to  piglets/supplementing/medication/immunisation ✔ (1) 
B – Prevent tail biting/cannibalism ✔ (1) 
3.2.3 Mineral administered to piglets 
Iron/Fe ✔ (1) 
3.2.4 Justification with TWO reasons 

  • Sow milk contains a limited quantity of iron/not enough✔ 
  • Most effective way to administer iron/Fe ✔ 
  • Initial feed intake of piglets is low/inadequate to support their iron requirements ✔ (Any 2) (2)

3.3 Body temperature and the lower critical temperature  
3.3.1 Bar graph showing the lower critical temperatures of the  different farm animals 
ANSWERTO GRAPH

Criteria/rubric/marking guidelines  

  • Correct heading ✔ 
  • X-axis – correctly calibrated with label (Farm animals) ✔ 
  • Y-axis – correctly calibrated with label (Lower critical temperature) ✔
  • Correct units (°C) ✔ 
  • Bar graph ✔  
  • Accuracy ✔ (6) 

3.3.2 Identification of the animal inefficiently using feed 
Piglets ✔ (1) 
3.3.3 Reason for dairy cows producing milk at 6°C.  
Their critical temperature is lower than 6°C ✔ (1) 
3.4 Life cycle of a parasite  
3.4.1 Classification and name the parasite above 

  • Internal parasite ✔ 
  • Liver fluke ✔ (2)

3.4.2 Letter representing  

  1. An intermediate host - D ✔ (1)
  2. Eggs hatch into larva - C ✔ (1) 

3.4.3 Precautionary measure  

  • Keep animals away from moist/wet places/camping off infested ✔
  • Control intermediate host (snails) burn infested areas✔
  • Keep areas around drinking places dry✔
  • Breed resistant animals✔
  • Graze animals on clean pastures/apply hygienic measures/use of  feeders✔
  • Zero grazing/ rotational grazing✔
  • Provision of clean drinking water✔
  • Provision of good nutrition✔
  • Deworming animals at certain intervals✔
  • Isolation/separation of animals✔ (Any1) (1) 

3.4.4 THREE economic implications of the parasite  

  • Decrease/poor/degradation of products/loss of production✔ 
  • Higher production costs/labour/time/medicines/ decreased  profits/income ✔ 
  • Poor reproduction outputs ✔  
  • Poor food conversion rate✔ 
  • Negative impact on economy/no export✔ (Any3) (3)

3.5 Passage on chicken housing  
3.5.1 TWO purposes of housing 

  • To protect chickens from predators ✔ 
  • To create an environment for growth and development ✔ (2) 

3.5.2 TWO to consider when building a chicken house 

  • Building to be cost effective ✔ 
  • Orientation of the building to be east to west ✔ 
  • Building site to be well drained and aerated✔ 
  • Roofing material should be insulated and be reflective✔ 
  • Enough ventilation✔ 
  • Even distribution of light✔ 
  • Should provide the right amount of heat✔ (Any 2) (2) 

3.5.3 TWO examples of equipment in a poultry house 

  • Feed troughs ✔ 
  • Water drinkers/troughs ✔ 
  • Lighting ✔ 
  • Nesting boxes ✔ 
  • Roosts ✔ 
  • Bedding ✔  
  • Foot baths ✔  
  • Air conditioning/fans/heaters✔ 
  • Incubators✔ 
  • Thermometer✔ 
  • Egg trays✔ 
  • Egg scales✔ (Any 2) (2)

[35]

QUESTION 4: ANIMAL REPRODUCTION 
4.1 Embryo and foetus development 
4.1.1 Identification of the structures  

  1. B – Allantois ✔
  2. E – Foetus✔ 
  3. F – Umbilical cord/placenta ✔ (3)

4.1.2 Provision of the following : 

  1. ONE function
    • Protection of the foetus against shock/shock absorber ✔
    • Prevents desiccation of the foetus/dehydration/drying of foetus ✔
    • Lubrication of birth canal✔
    • Regulates temperature around the foetus✔ (Any 1) (1)
  2. ONE constituent of D 
    • Amniotic fluid/water/liquid ✔  (1)
  3. Place where D occurs 
    • Inside amnion/C ✔ (1) 

4.1.3 Time to detect rectal pregnancy 
3–4 months into pregnancy/gestation ✔ (1)
4.2 Role of hormones  
4.2.1 Explanation of hormone  

  • The chemical substance secreted by endocrine glands/ovaries/ uterus transported in the blood ✔to specific parts/target organ of the body performing specialised functions ✔ (2) 

4.2.2 Primary function of hormones 

  1. Testosterone  (1)
    • Development of the secondary male characteristics ✔ 
    • Enhances sexual desires✔
    • Stimulate sperm production✔
  2. Luteinising hormone (LH)
    • Rapture the membrane of the follicle during ovulation ✔
    • Tightening the infundibulum around the ovary ✔
    • Stimulates secretion of progesterone✔
    • Maturation of the oocytes✔ 
    • Formation of the corpus luteum ✔ (Any 1) (1)
  3. Oestrogen  
    • Develop the functions of the secondary sex organs ✔
    • Responsible for the onset of oestrus/behaviour changes ✔ 
    • Signs of oestrus ✔
    • Contraction of the uterus ✔
    • Promote growth of the mammary duct system ✔
    • Stimulates Graafian follicle✔
    • Stimulates secretion of LH✔
    • Delays/inhibits secretion of FSH✔
    • Increases blood supply to the uterus✔
    • Prevents bacterial infection of the uterus✔ (Any 1) (1)

4.2.3 Hormone responsible for : 

  1. Maintaining the Corpus luteum – Progesterone ✔ (1)
  2. Growth and development of the Graafian follicle – FSH ✔ (1) 

4.3 Oestrus cycle of dairy cattle 

4.3.1 Determination of the number of cows on oestrus 
10 ✔ (1) 
4.3.2 Indication of time 20 cows will be in oestrus 
18:00 to 00:00 ✔ (1) 
4.3.3 Tendency of cows in oestrus from 12:00 to 06:00 
Increase/higher/more/from 10 to 45 cows ✔ (1) 
4.3.4 The number of cows in oestrus from 18:00 to 06:00 
20 + 45 cows ✔ 
= 65 cows✔ (2) 
4.3.5 Best time to inseminate 
12:00 to 18:00/in the afternoon✔ (1) 
4.3.6 Reason  
Time when most (45 cows) are in oestrus/in heat ✔ (1) 

4.4 The udder of a dairy cow  

4.4.1 Identification of the parts  

    • A – Alveolus ✔  (1)
    • B – Lobe ✔  (1)
    • C – Teat ✔   (1)

4.4.2 Definition of lactation  

    • Period of milk production by female animals/cows ✔
    • Starting soon after parturition for an average of 305 days ✔
    • Involves the hormones prolactin and oxytocin ✔ (Any 2) (2) 

4.4.3 Comparison of milk and butterfat production 

    • Milk production increases until peak production thereafter it  decreases ✔
    • Butterfat production decreases until peak production thereafter  it increases ✔ (2) 

4.5 Difficult births  
4.5.1 Scientific term for difficult births
Dystocia ✔  (1)

4.5.2 Reason for difficult births in heifers 

  • Heifers are physically smaller✔and less developed  (younger)/age ✔ 
  • Incorrect presentation/position/posture✔ 
  • Too large foetus/hydrocephalus✔ 
  • Deformities of the foetus✔ 
  • Torsion/twisting of the foetus✔ 
  • Prolapsed uterus✔ 
  • Multiple births/twins✔ 
  • Size of pelvic area✔ 
  • Weak/ ineffective labour✔ 
  • Cervix failing to dilate✔ 
  • Prolonged gestation/pregnancy period✔ 
  • Malnutrition✔ 
  • Diseases✔ (Any 2) (2) 

4.5.3 TWO managerial measures to reduce difficult births 

  • Use bulls renowned for small calves/low birth weight ✔  
  • Mate heifers at the ideal age/mass/not too early ✔  
  • Use a controlled/well-planned breeding season ✔  
  • Well planned feeding programme/avoid overfeeding✔  
  • Planned health programme ✔ (Any 2) (2) 

4.5.4 Definition of placenta retention 

  • The failure to expel the placenta/membranes ✔ 
  • within 12 hours after parturition/birth ✔ 
  • with negative effects/complications ✔ (Any 2) (2)

[35] 
TOTAL SECTION B: 105 
GRAND TOTAL: 150

Last modified on Friday, 02 July 2021 12:14