HOLIDAY WORK S5.
NOTE: This work should be done in a separate book well organised and must be
handed in on the reporting desk.
Nutrition
1. What is a limiting factor? (03 marks)
Describe a state where carbon dioxide is a limiting factor in photosynthesis (04 marks)
Give three differences between the light dependent and light independent reactions of
photosynthesis. (03 marks)
2. In an investigation to study the effect of light on the physiology and spirogyra, its amount
of phosphoglyceric acid (PGA), ribulose by-phosphate (RuBP) and sucrose were
measured at different intervals of time in the presence of light. At the 30th minute, light
was removed completely. The results obtained are shown in the graph below. Study it
and answer the questions that follow:
a. Compare the changes in the amount of
PGA and RuBP with time. (04 marks)
b. Explain the changes in the amount of the
following with time.
PGA, RUBP, Sucrose
(16 marks)
c. Explain how carbon dioxide is fixed by C4
plants. (05 marks)
d. List the various ways in which C3 plants
and C4 plants (05 marks)
3. (a). How are leaves adapted to perform their functions? (14 marks)
(b). Describe the importance of leaves to plants (06 marks)
4. (a). Describe the significance of pigments and light in photosynthesis (12 marks)
(b). How does altitude affect the distribution of C3 and C4 plants? (08 marks)
Cytology:
5. (a). Describe the structure and arrangement of the phospholipids in a cell (03 marks)
(b). How do properties of phospholipids maintain cell membrane structure (06 marks)
(c). Compare prokaryotic and eukaryotic cells (11 marks)
6. (a). How do the components of the plasma membrane ensure its fluidity? (06 marks)
(b). Relate the function of each of the following to the fluidity and porosity of their
membranes
(i). Plasma membrane (06 marks)
(ii). Rough endoplasmic reticulum (RER) (05 marks)
(iii). Golgi apparatus (03 marks)
7. Explain the role of membranes is related to its functions (20 marks)
8. (a). Describe the structure of the nucleus in a cell (07 marks)
(b). Outline the functions of the nucleus (07 marks)
Develop A Sense Of Urgency 1
(c). How is the nucleus adapted to perform the above functions in (b) above (06 marks)
Ecology
9. Figure below shows the changes in the number of species, biomass and the net
productivity in an area. Study the figure and
answer the following questions.
(a).Describe the changes in the number of
species, biomass & net productivity in the
area (06 marks)
(b).How are the numbers of plant species,
biomass and net productivity related? (13
marks)
(c)(i)Name the process at 160 years? (01
marks)
(d). Account for the changes in the number’s of species between 0 and 50 years. (08
marks)
(e). Suggest the starting ecosystem for this forest. (01 marks)
(f) Which other ecosystem could undergo similar changes? (02 marks)
(g) Mention the factors that can interrupt the process of change illustrated. (03 marks)
10. (a). Giving examples, describe the uses of nitrogen to plant and animal bodies. (05
marks)
(b). How is concentration of nitrogen maintained at a constant level in nature? (15
marks)
11. (a)What is meant by:
(i) biotic potential (03 marks)
(ii) Primary productivity (02 marks)
(b) Discuss the factors which influence the size of populations in an ecosystems. (12
marks)
12. (a)Explain the different activities that result in pollution. (10 marks)
(b). Explain the effect of water pollution on an aquatic ecosystem. (10 marks)
Classification
13. (a)What is meant by the term a species (04 marks)
(b)State the relevance’s of classifying living organisms (05 marks)
(c)Outline the characteristics of mitochondria that support the idea that they where
once prokaryotes (05 marks)
14. (a)(i).Briefly describe and explain the classical growth curve exhibited by a bacteria
(ii).How does a bacterial cell differ from that of a higher plant (06 marks)
(b).Giving examples, describe the different nutritional groups of bacteria (07 marks)
(c).Discuss the importance of bacteria in nature (07 marks)
15. (a). Distinguish between a life cycle and alternation of generations. (02 marks)
(b). Give an account of alternation of generation in a named bryophyte or pteridophyte
(12 marks)
(c). Discuss the significance of alternation of generations in life cycle of plants (06
marks)
16. (a)Explain how ferns are better adapted to terrestrial life than mosses (08 marks)
(b)How does temperature influence the following processes in plants
(i). Plant growth (07 marks)
(ii). Plant distribution (05 marks)
Develop A Sense Of Urgency 2
Histology
17. (a).How are the following tissues related to functions
i. Parenchyma tissues
ii. Collenchyma tissues
iii. Sclerenchyma tissues
(b). State the functions of bones in animals. (05 marks)
18. (a).How is the chloroplast suited for function (08 marks)
(b).Describe the modifications of parenchyma tissues in the different parts of the plant and
state functions.
(c). Explain the distribution pattern of mechanical tissues in plants. (05 marks)
19. (a). With examples, classify glandular tissues according to the mechanism of secretion
(08 marks)
(b).Explain how the structure and distribution of glandular tissues in vertebrates is related
and adapted to function (12 marks)
Chemicals of Life
20. (a)Explain the significance of the physical properties of water to organisms (13 marks)
(b).Outline the importance of acids and bases to living organisms (05 marks)
21. Starch and cellulose are important polysaccharides in plants
(a).Compare the structures of starch and cellulose (11 marks)
(b).Describe the role of carbohydrates in plant life (09 marks)
Genetics
22. (a).State Mendel’s laws of genetic inheritance (02 marks)
(b).Using meiosis, explain how the laws described in (a) above operate (12 marks)
(c).Explain why Mendel used garden peas for his experiments (06 marks)
23. (a).Explain what is meant by sex linked and sex limited traits (05 marks)
(b).Giving examples, discuss the inheritance of sex linked and autosomal traits (10
marks)
(c).Explain using an appropriate example why many sex-linked diseases occur more
frequently in men than women. (05 marks)
24. (a).How is sex determined in humans? (04 marks)
(b).A woman has four sons, one of whom is a haemophiliac and the other three are
normal.
(i). What are the possible genotypes of the woman and her husband (12 marks)
(ii) Is it possible for the couple to have a haemophiliac daughter? Explain your
answer (04 marks)
You have ten days do with them the most.
Nice holidays.
Bio Dept
Develop A Sense Of Urgency 3
