Life Sciences Grade 11 P1 Eastern Cape November 2024 Memo

NATIONAL SENIOR CERTIFICATE GRADE 11 NOVEMBER 2024 LIFE SCIENCES P1 MARKING GUIDELINE MARKS: 150 This marking guideline consists of 11 pages. Hosted by www.ecexams.co.za.

2 LIFE SCIENCES P1 (EC/NOVEMBER 2024) PRINCIPLES RELATED TO MARKING LIFE SCIENCES 1. If more information than marks allocated is given Stop marking when maximum marks is reached and put a wavy line and ‘max’ in the right-hand margin. 2. If, for example, three reasons are required and five are given Mark the first three irrespective of whether all or some are correct/incorrect. 3. If whole process is given when only a part of it is required Read all and credit the relevant part. 4. If comparisons are asked for but descriptions are given Accept if the differences/similarities are clear. 5. If tabulation is required but paragraphs are given Candidates will lose marks for not tabulating. 6. If diagrams are given with annotations when descriptions are required Candidates will lose marks. 7. If flow charts are given instead of descriptions Candidates will lose marks. 8. If sequence is muddled and links do not make sense Where sequence and links are correct, credit. Where sequence and links are incorrect, do not credit. If sequence and links become correct again, resume credit. 9. Non-recognised abbreviations Accept if first defined in answer. If not defined, do not credit the unrecognised abbreviation, but credit the rest of the answer if correct. 10. Wrong numbering If answer fits into the correct sequence of questions but the wrong number is given, it is acceptable. 11. If language used changes the intended meaning Do not accept. 12. Spelling errors If recognisable, accept the answer, provided it does not mean something else in Life Sciences or if it is out of context. 13. If common names are given in terminology Accept, provided it was accepted at the national memo discussion meeting. 14. If only the letter is asked for but only the name is given (and vice versa) Do not credit. Copyright reserved Please turn over Hosted by www.ecexams.co.za.

(EC/NOVEMBER 2024) LIFE SCIENCES P1 3 15. If units are not given in measurements Candidates will lose marks. Marking guideline will allocate marks for units separately. 16. Be sensitive to the sense of an answer, which may be stated in a different way. 17. Caption All illustrations (diagrams, graphs, tables, etc.) must have a caption. 18. Code-switching of official languages (terms and concepts) A single word or two that appear(s) in any official language other than the learners’ assessment language used to the greatest extent in his/her answers should be credited if it is correct. A marker that is proficient in the relevant official language should be consulted. This is applicable to all official languages. Copyright reserved Please turn over Hosted by www.ecexams.co.za.

4 LIFE SCIENCES P1 (EC/NOVEMBER 2024) SECTION A QUESTION 1 1.1 1.1.1 D  1.1.2 C  1.1.3 B  1.1.4 A  1.1.5 A  1.1.6 C  1.1.7 A  1.1.8 D  1.1.9 C  (9 x 2) (18) 1.2 1.2.1 Chloroplast  1.2.2 Intercostal  muscle 1.2.3 Ureter  1.2.4 Alveoli  1.2.5 (Palisade) mesophyll / chlorenchyma  1.2.6 Photolysis  1.2.7 Pleural  membrane 1.2.8 Oxygen  1.2.9 Islets of Langerhans  (9 x 1) (9) 1.3 1.3.1 B  only 1.3.2 NONE  1.3.3 BOTH A and B  1.3.4 BOTH A and B  (4 x 2) (8) 1.4 1.4.1 Trachae  (1) 1.4.2 - Part D/ diaphragm contracts  - increasing the volume of the thoracic cavity  (2) 1.4.3 - The sides of the model is immovable  / in the human chest the rib cage moves upwards and downwards - The space between the lungs and wall of the thorax is very small  / the model shows a large space between the balloons and glass jar - In the body there is limited movement of lungs  / pressure exerted on lungs / in the model there is a lot is of space available for lungs to move / greater pressure is placed on balloons - In the human body, the diaphragm is dome-shaped and flattens during inhalation.  / In the model, the rubber sheet is flat and is pulled down to represent inhalation (MARK FIRST TWO ONLY) (2) Copyright reserved Please turn over Hosted by www.ecexams.co.za.

(EC/NOVEMBER 2024) LIFE SCIENCES P1 5 1.5 1.5.1 (a) Bronchus  (1) (b) Rib  (1) 1.5.2 • Well protected  The ribs and intercostal muscles protect the lungs from mechanical injury  • Large surface area  Many alveoli are present that increase surface area for gaseous exchange to take place  • Moist  Alveoli are lined with a mucous layer  • Thin surface  Alveoli are only one cell layer thick  MARK FIRST TWO ONLY (Any 2 x 2) (4) 1.5.3 (a) G  – Larynx  (2) (b) A  ‒ Trachea  (2) [50] TOTAL SECTION A: 50 Copyright reserved Please turn over Hosted by www.ecexams.co.za.

6 LIFE SCIENCES P1 (EC/NOVEMBER 2024) SECTION B QUESTION 2 2.1 2.1.1 AMOUNT OF TIME IN SECONDS TO RELEASE 20 BUBBLES UNDER DIFFERENT TYPES OF LIGHT No. of bubbles produced in 20 180 160 160 140 120 100 80 80 seconds 60 40 40 20 0 Blue Green Red Colour of light Criteria Mark allocation Correct type of graph (T)  Caption of graph includes both variables (C)  Correct scale for y-axis and equal width of bars (S)  Correct labels on the x-axis and y-axis with correct  unit on the y-axis (L) Plotting of bars correctly done for: (P) 1‒2 bars  All 3 bars  (6) 2.1.2 • Higher bubble production means a greater rate of photosynthesis  • thus greater plant growth  (2) 2.1.3 Green : Red 160 : 80  2:1 (2) 2.1.4 Blue  light (1) 2.2 2.2.1 • Space in the thoracic cavity would be limited  • Due to abdominal organs pushing into the thoracic cavity  • Limiting the ability of the lungs to fully expand  OR • The thoracic cavity is no longer a closed system  • When the diaphragm contracts the thoracic cavity will not expand  • Pressure will not decrease in the thoracic cavity  • And air will not be drawn into the lungs (3) Copyright reserved Please turn over Hosted by www.ecexams.co.za.

(EC/NOVEMBER 2024) LIFE SCIENCES P1 7 2.2.2 • Carbon dioxide in the blood increased  due to difficulty in breathing • Which was detected by (chemo) receptors of the aorta / carotid artery • Which stimulate the Medulla Oblongata  • to send impulses to heart muscle  • to increase (rate and depth of) the hearts contractions  (5) 2.3 2.3.1 To determine if living organisms require oxygen for aerobic respiration.  (2) 2.3.2 (a) Oxygen  uptake (1) (b) Aerobic respiration  (1) 2.3.3 28−13  x 100  13 = 115,38%  (3) 2.3.4 • Both flasks have the same amount of sodium hydroxide solution  • To ensure carbon dioxide absorption occurs equally in both flasks  OR • Both insect and glass beads have the same mass  • Therefore starting positions have the same pressure  (Mark first ONE only) (Any 1 x 2) (2) 2.4 2.4.1 • Pyruvate/ pyruvic acid is broken down  • Releasing hydrogen  atoms and • carbon dioxide  • in the presence of oxygen  (Any 3 x 1) (3) 2.4.2 • In animal cells pyruvate/pyruvic acid is (partially) broken down into lactic  acid • due to lactic acid fermentation /plant cells can’t convert ethanol and carbon dioxide back into pyruvate • In plant cells pyruvate/pyruvic acid is (partially) broken down into ethanol and carbon dioxide  • due to alcoholic fermentation  / animal cells can convert lactic acid back into pyruvate (4) 2.4.3 • Alcoholic fermentation can be used to form alcohol  • which can be sold for income  OR • It can be used to make bread dough rise  • a greater volume of product is produced at a greater profit  (Mark first TWO only) (4) Copyright reserved Please turn over Hosted by www.ecexams.co.za.

8 LIFE SCIENCES P1 (EC/NOVEMBER 2024) 2.4.4 Muscle cramps  / spasms (1) 2.5 2.5.1 • Light  • Temperature  • Water / rainfall (Mark first TWO only) (Any 2 x 1) (2) 2.5.2 • (The light independent phase of) photosynthesis had been taking place  • This phase uses carbon dioxide to produce glucose  (2) 2.5.3 • Excess carbon dioxide would be a wasted expense  • Plants cannot use any more Carbon dioxide as plants would not be able to absorb beyond a set maximum /Chloroplasts could become saturated with carbon dioxide • Excess carbon dioxide could become toxic  for plant growth (Any 2 x 1) (2) 2.5.4 • (Aerobic) cellular respiration  would occur • Glucose is broken down  • in the presence of oxygen  • (Water and) carbon dioxide would be released  (4) [50] Copyright reserved Please turn over Hosted by www.ecexams.co.za.

(EC/NOVEMBER 2024) LIFE SCIENCES P1 9 QUESTION 3 3.1 3.1.1 (a) C  – Distal Convoluted Tubule  (2) (b) D  – Ascending limb of Henle  (2) 3.1.2 - Capillary has microscopic pores  only allowing smaller components of blood through  - Dense capillary network / cup shaped Bowman’s capsule Increasing surface area for filtration to occur  - Afferent arteriole wider than efferent arteriole  Placing blood under pressure within the glomerulus increasing filtration - Podocytes lining of Bowman’s capsule  form filtration slits  (Mark first THREE only) (Any 3 x 2) (6) 3.1.3 (a) - Active reabsorption  - Energy/ATP produced by cuboidal epithelial cell used /pulling of glucose against the concentration gradient (2) (b) - Passive reabsorption /osmosis  - Water is moved from a region of high concentration to a region of low concentration  (2) 3.1.4 • More ADH produced  means • They/B and C/distal convoluted tubules and collecting duct become more permeable  • More water leaves the renal tubules  • More water reabsorbed into the blood /medulla (Any 3 x 1) (3) 3.2 3.2.1 Urea  (1) 3.2.2 • Proteins are too large  • To move through the pores of the glomerulus  (2) 3.2.3 • Aldosterone * will not be secreted • causing the renal tubule to become impermeable to Na + /sodium ions will not be reabsorbed  from the filtrate (2) 3.2.4 • Diabetes mellitus  • High glucose level in the urine  • Insulin is not being produced  therefore no regulation (3) Copyright reserved Please turn over Hosted by www.ecexams.co.za.

10 LIFE SCIENCES P1 (EC/NOVEMBER 2024) 3.3 3.3.1 (a) Liver  (1) (b) Rectum  (1) (c) Gall bladder  (1) 3.3.2 • Provides low pH / acidic conditions for enzymes to function / chemical digestion • Kills bacteria / pathogenic microbes (Mark first TWO only) (2) 3.3.3 • The small intestine is long  to increase the time/surface area for absorption of products  • The walls of the small intestine are folded  to increase surface area of absorption  • The inner wall of the small intestine have villi  to increase surface area of absorption  • Each villus contains microvilli  to further increase the surface area for absorption  (Mark first TWO only) (Any 2 x 2) (4) 3.3.4 Liver  / A (1) 3.3.5 • Emulsification of fats  Assisting in the absorption of lipids  • Neutralisation of acidic chyme  to prevent damage to the small intestine  / provide correct pH for enzymes to function (Mark first ONE only) (Any 1 x 2) (2) 3.3.6 Cross-section of the small intestine Serosa Longitudinal muscle Mucosa Circular muscle Caption (C) (1) Correct Drawing (D) (1) Three correct labels (L) (3) (5) Copyright reserved Please turn over Hosted by www.ecexams.co.za.

(EC/NOVEMBER 2024) LIFE SCIENCES P1 11 3.4 3.4.1 (a) • Glycerol and fatty acid tails  • C (2) (b) • Glucose  • A (2) 3.4.2 (a) • Smaller surface area  • For the reabsorption of nutrient monomers  • Due to less nutrients/glucose/amino acids/glycerol and fatty acids present in the blood  • The individual’s body will not be able to sustain its nutritional needs /respiration • Person my get tired more often / has less energy • Leading to health complications  / disease / infections (Any 4 x 1) (4) [50] TOTAL SECTION B: 100 GRAND TOTAL: 150 Copyright reserved Please turn over Hosted by www.ecexams.co.za.