Microsoft word - life sciences p2 nov 2011 memo eng version 1.doc

NATIONAL
LIFE SCIENCES P2
VERSION 1 (NEW CONTENT) FOR FULL-TIME CANDIDATES
NOVEMBER 2011


MARKS: 150

This memorandum consists of 11 pages.
Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum
PRINCIPLES RELATED TO MARKING LIFE SCIENCES 2011
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. If, for example, three reasons are required and five are given
Mark the first three irrespective of whether all or some are correct/incorrect. If whole process is given when only part of it is required
Read all and credit relevant part. If comparisons are asked for and descriptions are given
Accept if differences / similarities are clear. If tabulation is required but paragraphs are given
Candidates will lose marks for not tabulating. If diagrams are given with annotations when descriptions are required
Candidates will lose marks If flow charts are given instead of descriptions
Candidates will lose marks. If sequence is muddled and links do not make sense
Where sequence and links are correct, credit. Where sequence and links is
incorrect, do not credit. If sequence and links becomes correct again, resume
credit.
Non-recognized abbreviations
Accept if first defined in answer. If not defined, do not credit the unrecognized
abbreviation but credit the rest of answer if correct.
Wrong numbering
If answer fits into the correct sequence of questions but the wrong number is
given, it is acceptable.
If language used changes the intended meaning
Spelling errors
If recognizable accept provided it does not mean something else in Life
Sciences or if it is out of context.
If common names given in terminology
Accept provided it was accepted at the national memo discussion meeting. Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum If only letter is asked for and only name is given (and vice versa)
No credit
15. If units are not given in measurements
Candidates will lose marks. Memorandum will allocate marks for units separately Be sensitive to the sense of an answer, which may be stated in a different
way.
Caption
All illustrations (diagrams, graphs, tables, etc.) must have a caption
Code-switching of official languages (terms and concepts)
A single word or two that appears 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.
No changes must be made to the marking memoranda without consulting the Provincial Internal Moderator who in turn will consult with the national Internal Moderator (and the External Moderators where necessary) Only memoranda bearing the signatures of the National Internal Moderator and the UMALUSI moderators and distributed by the national Department of Basic Education via the provinces must be used during training and during the marking period. Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum SECTION A

QUESTION 1
1.2 1.2.1 Vasodilation3 +3 (accept any answer/ no answer)
Pollination3 (8 x 1) 1.5 1.5.1 C – Petal 3/corolla TOTAL SECTION A: 50
Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum
SECTION B

QUESTION 2
A – Tympanic membrane3/ Tympanum/Eardrum C – Oval window3/fenestra ovalis D – Round window3/fenestra rotunda B – transmit vibrations3 from the tympanic membrane to inner ear/ amplifies sound waves D – prevents pressure build up of waves3/absorbs pressure wave set up by tympanic canal of the inner ear/eases sound waves out of inner ear/ prevents sound waves from moving backwards in Tympanic membrane/A has a larger surface area3 than the oval Ossicles will not vibrate freely 3 to transmit vibrations to the inner ear3/ causing partial deafness Cannot equalise pressure 3on either side of tympanic membrane leading to pain3/ middle ear infection/ a burst eardrum / vibrations not being transmitted/ partial deafness 2.2 2.2.1 (a) 73 (b) Diameter of the pupil is the largest3, indicating dim light conditions3/ allowing more light to enter Since less light enters the eye radial3 muscles of the iris [contract]3
circular3 muscles of the iris [relax]3
- causing the pupil to dilate3/become wider/become bigger thus allowing more light to enter any [ ] = only allocate mark if linked to correct muscle
Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum Day 0–63/day 0–7 Stimulates follicle3/ovum development in the ovary/secretion of An increase in progesterone level3 inhibits the release of FSH3 FSH stimulates the development of the ovum3 and progesterone prepares for implantation 3when this ovum is fertilised - Corpus luteum 3 - starts to secrete progesterone3 - which thickens3 the lining of the uterus wall/endometrium - Corpus luteum has degenerated3 - Progesterone level has decreased3 - FSH level starts to rise3 - LH level decreases3 (Mark first TWO only)
Moist3 and dark3 conditions - The other two dishes should have had dry paper3 put in so that all the four dishes had the same paper3/ to avoid introducing a new variable - Test one variable at a time/light and moisture conditions separately3 to determine which environmental factor 3 was preferred by the woodlice - Repeat the investigation3 to increase reliability3 - Ensure sufficient time3for the movement 3of the woodlice - Use the same species3/sex/age of woodlice as they might behave differently3/this avoids the introduction of a new variable (Mark first ONE only)
(2)
(4)
[30]
Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum
QUESTION 3
- Obtain permission to catch fish/use dam3 - Conduct training to identify the Tilapia sparrmanii 3 - Decide when to do the investigation3 - Decide on the tags3 /markers/apparatus to be used - Decide on the method of catching3 - Determine the sample size3/number of repeat samples
- Determine the period between the two successive captures3
- Decide on how to record the results3
(Mark first FOUR only) Any
Number of Tilapia sparrmanii (P) = (15 x 150) 3 Logistic3 growth form/S-shaped/sigmoid A = Lag 3/Establishment phase B = Exponential 3 /Geometric/accelerating/log/logarithmic phase C = Equilibrium 3 /Stationary/Stabilising/Constant phase - Environmental resistance increased 3 - causing the carrying capacity of the area to be reached3 - leading to increased competition 3 - resulting in the death rate increasing to equal the birth - or resulting in increased emigration that balances with - Population is acclimatising/adapting to its new environment3 - Few pairing partners3 - Time required for producing offspring is relatively long3 - Not all individuals are sexually mature3 (Mark first TWO only)
3.3 3.3.1 Residents3 Mining company3 /Exxaro KZN Sands Amakhosi and tribal leaders 3 (Mark first THREE only)
Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum Two advantages
- Creating new jobs3 - Job reservation/job losses prevented3 - Contribute to the economy of the town3/income to municipality from tax rates will increase through businesses - Minerals available more cheaply3 - Develops infrastructure of the town3 Two disadvantages
- Health implications3 - Decrease of the property values of the residents3 - Income to municipality from tax rates will decrease3 through decline in property value - Exploitation of the community3 - Loss in biodiversity3 - Increase in pollution3 - Environmental degradation3 - Conflict in the community3 (Mark first TWO only)
(a) Resource /Spatial/niche partitioning3 (b) Intraspecific3 competition (c) Competitive exclusion 3 principle/interspecific competition - Different species 3 - coexist in the same habitat 3 - eating leaves of plant at different heights3/use the resources slightly differently - minimising competition3 Any (3)
(6)
[30]
TOTAL SECTION B: 60
Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum
SECTION C

QUESTION 4

4.1
Human population size from 1650 to 2050 3
learner's Y axis 2000 (500) 1000 (500) Human population size
(millions)
Time/year

Guideline for the assessing the graph
Correct type of graph and joining of points Title of graph Correct label and scale x-axes Correct label and scale y-axes Plotting of points of line graph 1: 3 to 4 points plotted correctly 2: All 5 points plotted correctly NOTE: If the wrong type of graph is drawn: marks will be lost for
correct type of graph - 1 mark plotting of points – 2 marks If labels of the axes are transposed then marks will be lost be for:
correct label and scale for X and Y axes – 2 marks Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum (a) Read from the learners graph (value3 and for million 3/000 000)
(b) 200 3 years 3 3for infrastructure development e.g. housing 3for services in the future e.g. education - To have strategies3/ any example to improve the sustainability of the environment (Mark first TWO only)
4.2 4.2.1 The cell elongation3 in the coleoptile will increase3/decrease/remain the same/differ as the auxin concentration increases/decreases/differs3 Removing the effect of auxin 3produced at the tip as there can be varying concentrations3 produced by each plant Type of soil3/ amount of water/ light intensity/ temperature/ size of the pot/ keep environmental conditions the same Increasing the concentration of auxin results in an increase in the cell elongation3 up to an optimum concentration3 then it starts inhibiting/decreasing the cell elongation3 Copyright reserved Please turn over Life Sciences/P2 (Version 1) (Full-time) DBE/November 2011 NSC – Memorandum - When abnormal levels of glucose are detected3 - by the pancreas3, - the Islets of Langerhans3 secretes hormones - into the bloodstream3 When blood glucose level rises3
- Insulin3 is secreted - to decrease the blood glucose level3 - back to normal3 - insulin secretion is then inhibited3 When blood glucose level falls3
- Glucagon3 is secreted - to increase the blood glucose level3 - back to normal3 - glucagon secretion is then inhibited3 Causes of diabetes mellitus
- Non-secretion of insulin3 - Production of defective insulin3 - Body cells resistant to the action of insulin3 - Inability of the cells to use glucose efficiently3 Any Symptoms
- Glucose in the urine3 - Fatigue3/lethargy/faintness - Nausea3/Vomiting - Non-healing of wounds3 Management of diabetes mellitus
- Eating diet suitable for diabetic person3 - Using prescribed medication/drugs 3for the management of diabetes mellitus Content (17)
ASSESSING THE PRESENTATION OF THE ESSAY
Marks Descriptions
Well structured – demonstrates insight and understanding of question Minor gaps or irrelevant information in the logic and flow of the answer Significant gaps or irrelevant information in the logic and flow of the answer Not attempted/nothing written other than question number/no relevant information Synthesis (3)
TOTAL SECTION C:
GRAND TOTAL: 150
Copyright reserved

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