(a) T- Polar nuclei;
R-Egg cell;
b) Ovule;
c) T fuses with one male nucleus; to form a primary endosperm;
R fuses with another male nucleus; to form a zygote;
d) Double fertilization

(a) Lumbar vertebrae; rj. wrong spelling
R j. without vertebrae
b) Extra processes;
-Long transverse process stauting sideways;
-Broad D-shaped Centrum
c) L-Transverse process;
M-Metapophysis;
K-Neural spine;
d) Increase the surface area for attachment of (abdominal) muscles;
e) Anterior view;

(a) Anaerobic respiration;
ii)Absence of oxygen;
b)

i)To remove;/drive off oxygen
ii) Forms a white precipitate; rj turns milky
c)

–use water instead of 10% glucose solution/
-Use boiled yeast instead of unboiled yeast

b) Vessel A – The pressure is low; and remains fairly constant;
Vessel B-The pressure is high; it rises and falls/drops within certain range;
c)i) Blood vessel A is a vein;
ii) Blood vessel B-is an artery;
iii) A is a vain because veins have low; and constant blood pressure;
B is an artery because it has a high pressure; the pressure also has wide fluctuation range due to the heart beat;
d) Exercise-sickness; Causes the heart to beat faster;

The diet contains carbohydrates/starch, proteins and lipids;
In the mouth (max 6)
-The mechanical breakdown of food using teeth; takes place. This increases the surface area for enzyme action;
-The food is moistened and lubricated by saliva; for easy swallowing;
-Enzyme ptyalin/salivary amylase; contained in the saliva, converts the starch in the ugali to maltose;
-The food is then rolled in to boluses; and pushed down the gullet by the tongue; the movement of food/bollus in the gullect occurs by peristalsis;
In the stomach (max 3)
Hydrochloric acid provides a suitable PH; to activate pepsinogen to pepsin;
-Pepsin converts protein in the meat into peptides and peptones;
-The food is then churned; by rhythmical contractions of the muscular wall of the stomach; to form chyme;
In the duodenum (max 6)
Bile; neutralizes the acidic chyme;
-Pancreatic amylase; converts starch to maltose;
-Trypsin; converts proteins in to peptides and peptones;
-Bile salts emulsify; the fats in the meat;
-pancreatic lipase; converts fats in to fatty acids and glycerol;
In the ileum (max 5)
-Maltase; converts maltose to glucose;
-Peptidase; converts peptides in to amino acids;
-Lipase converts fats into fatty acids and glycerol;
-Glucose and amino acid are then absorbed in to the blood stream through the villus;
-Fatty acids and glycerol are absorbed in to the lacteal l in the villus
(27 max 20)

Some xerophytes have thick/ fleshy/succulent stems; to store water; the thick waxy cuticle reduces water loss by transpiration;
-The leaves are needlelike /reduced to spines; to re duce the surface area; through which water is lost during transpiration
-The stems and branches are green/ have chloroplast; for photosynthesis;
-Some xerophytes have superficial roots; to provide a large surface area for absorbing maximum amounts of water (far below the surface)
-Most xerophytes have spines/thorns; which protect them against browsers;
-Some have leaves covered with hair /scales; to trap a layer of still moist air close to the leaf surface; thus reducing transpiration
-Some xerophytes roll their leaves; in dry weather to reduce the surface area exposed t o the external environment; thus reducing transpiration
-Xerophytes have reversed stomatal rhythm ;( whereby they open their stomata at night and close them at day time)
-Xerophytes have reduced number of stomata; and area sunken; to reduce the rate of transpiration.
- Xerophytes have a short life cycle; to maximize the use o f the short rainy season;
-Some have shallow extensive fibrous root system; to absorb water near the surface;
-Their seeds are resistant to dessication; and remain dormant yet viable for several years;
- Some xerophytes have perennating underground organs; e.g. Bulbs/corms; which store food /water;
(27 max 20)