Explain continental drift as an evidence of evolution.(Answered) What is meant by?
(a) Organic evolution?
(b)Continental drift?(Answered) What is meant by the following terms? Give an example in each case.
(i) Homologous structures.
(ii) Analogous structures.
(iii) Vestigial structures.(Answered) What is the difference between Darwinian and Lamarckian theories of evolution?(Answered) Distinguish between analogous and homologous structures(Answered) State two ways in which Homo sapiens differs from Homo habilis.(Answered) Distinguish between divergent and convergent evolution giving example in each case.(Answered) What is organic evolution?(Answered) Give reason why each of the following is important in the study of evolution:
(a) Fossils records.
(b) Comparative anatomy.(Answered) State two advantages of natural selection to organisms.(Answered) Discuss the various evidences, which show that evolution has taken place.
(Answered) State three pieces of evidence that support the theory of evolution.(Answered) Give a reason why it is only mutation in genes of gametes that can influence evolution.(Answered) Explain why Lamarck’s theory of evolution is not accepted by Biologists today.(Answered) State two limitations of using a quadrat to estimate the population of organisms.(Answered) Explain the importance of protecting the forest ecosystem with reference to the Pollution.(Answered) Explain the importance of protecting the forest ecosystem with reference to the Water conservation(Answered) Explain the importance of protecting the forest ecosystem with reference to the Biotechnology.(Answered) Explain the importance of protecting the forest ecosystem with reference to
the Biodiversity.(Answered) Explain the importance of protecting the forest ecosystem with reference to
the Climate change.(Answered) Other than using the quadrat, give two methods of estimating population of grass.(Answered) State two control measures for malaria.(Answered) Name the process through which free atmospheric nitrogen is converted into nitrates.(Answered) The diagram below represents a certain plant.
(a) What is the likely habitat for the plant?
(b) Give two reasons for your answer in (a) above.
(Answered) What is meant by the term Carrying capacity?(Answered) What is meant by the term Ecosystem ?(Answered) What is meant by the term Habitat?(Answered) The diagram below shows a transverse section of a leaf.
a)Name the habitat of the plant from which the leaf is obtained.
(b) Give two reasons for your answer in (a) above.
(Answered) Name a substance that is responsible for acid rain.(Answered) What is eutrophication?(Answered) Give an example of biological control.(Answered) What is meant by the term biological control?(Answered) State two ways in which aerenchyma tissues in aquatic plants are adapted to their function.(Answered) Other than using the quadrant, give two methods of estimating population of grass.(Answered) Name one process that is responsible for loss of energy from one trophic level to the next.(Answered) State three effects of dumping untreated sewage into a river.(Answered) Name the disease in humans caused by plasmodium falciparum.(Answered) Name the causative agents of the following diseases in humans.
(i) Typhoid.
(ii) Amoebic dysentery.(Answered) Name two benefits that a parasite derives from the host.(Answered) Describe the nitrogen cycle.(Answered) Describe how different parts of the cell organelles are adapted to their functions(Answered) State two characteristic of aerenchyma tissue.(Answered) Describe the three characteristics of a population.(Answered) Describe causes and methods of controlling water pollution(Answered) State one way by which HIV/AIDS is transmitted from mother to child.(Answered) State two ways in which schistosoma species is adapted to parasitic mode of life.(Answered) Name a method that could be used to estimate the population size of the following organisms:
(i) Fish in a pond.
(ii) Black jack in a garden.(Answered) Give three reasons for loss of energy from one trophic level to another in the food chain.(Answered) Distinguish between pyramid of numbers and pyramid of biomass.
(Answered) What is the importance of the following in an ecosystem?
(a) Decomposers
(b) Predation.(Answered) Name the organism that causes amoebic dysentery.(Answered) Explain how abiotic factors affect plants.(Answered) How is aerenchyma tissue adapted to its function?(Answered) What is meant by Synecology?(Answered) (a) What is meant by Autecology?(Answered) Name the causative agent of typhoid.(Answered) How are leaves of submerged plants adapted for photosynthesis?(Answered) Ascaris lumbricoides is an example for an endoparasite.
(a) The name Ascaris refers to?
(b) State the habitat of the organism.
(c) State three ways in which the organism is adapted to living in its habitat.(Answered) Explain why the carrying capacity of wild beasts is higher than that for cattle in a given piece of land.(Answered) (b) State the association of the bacteria named in (a) above with the leguminous plants.(Answered) The diagram below represents the nitrogen cycle.
(a) State the process labeled: A and D
(b) Name the compound represented by B.
(c) Name the group of organisms labeled C.
(d) (i) Name the group of plants which promote process A.
(ii) State the part of the plant where process A takes place.
(e) How would excess pesticides in the soil interfere with process A?(Answered) Why are green plants referred to as primary producers in an ecosystem?(Answered) Explain how leaves of mesophytes are suited to their functions.(Answered) What is the importance of a national park to a nation?(Answered) State four human activities that affect population of animals in game parks.(Answered) Explain how birds of prey are adapted to obtaining their food.(Answered) State two ways in which some fungi are beneficial to humans.(Answered) Give a reason why two species in ecosystems cannot occupy the same niche.(Answered) Explain how the various activities of man have caused pollution of air.(Answered) (a) Distinguish between a community and population.(Answered) Suggest three reasons why green plants are included in a fish aquarium.(Answered) The herbivorous mammalian species were introduced into an ecosystem at the same time and in equal numbers. The graph below represents their populations during the first seven years.
Study the graph and answer the questions that follow.
(a) (i) Which species has a better competitive ability?
(ii) Give reason for your answer.
(b) Account for the shape of the curve of species A between:
(i) One year (Answered) State two ways by which the human immuno deficiency virus (H.I.V) is transmitted through sexual intercourse?(Answered) Give two reasons why primary productivity in an aquatic ecosystem decreases with depth.(Answered) What is the relationship between leguminous plants and bacteria found in their root nodules?(Answered) Describe how the tapeworm is adapted to a parasitic mode of life.(Answered) The diagram below represents a simplified nitrogen cycle.
(a) Name the organisms that cause process E and J
(b) Name the process represented by F and H.
(c) Name the group of organism represented by G.(Answered) The diagram below represents a feeding relationship in an ecosystem.
(a) Write down the food chains in which the guinea fowls are secondary consumers.
(b) What would be the short term effects on the ecosystem if lions invaded the area?
(c) Name the organism through which energy from the sun enters the food wed.(Answered) Oil can be applied on the stagnant water to control the spread of malaria.
(a) How does this practice control the spread of malaria.
(b) Give a reason why this practice should be discouraged.(Answered) Describe how the quadrant method can be used to estimate the population of various species of plants in a given habitat.(Answered) The chart below shows a feeding relationship in a certain ecosystem.
(a) Construct two food chains ending with a tertiary consumer in each case.
(b) Which organism has the largest variety of predators in the food web?
(c) Name secondary consumers in the food web.(Answered) State two ways in which xylem vessels are adapted to their function.(Answered) The diagram below represents a transverse section of a young stem.
(b) State the functions of the parts labeled C, D, and E.
(c) List three differences between the section shown above and one that would be obtained from the root of the same plant.(Answered) The diagram below illustrates a specialized cell obtained from a certain tissue.
(a) Name the cell.
(b) State two ways in which the cell is structurally adapted to its function.(Answered) The diagram below represents a nucleus.
(a) (i) Name the structures labeled E and F.
(ii) State the function of F.(Answered) Name the plant cell organelle:
(i) That stores chlorophyll
(ii) Responsible for intracellular digestion.(Answered) With reference to the nucleus, state one difference between an animal and a bacterial cell.(Answered) State two main functions of the vacuole in the amoeba.(Answered) Give one reason why the coarse adjustment knob should not be
used to lower the high power objective.(Answered) State the function of a mirror in a light microscope.(Answered) Below are diagrams of a cell organelle obtained from different organs of an animal.
(i) For each organelle, state an organ in the urinary system where it is likely to be found.
ii) Give a reason for your answer in (a) (i).(Answered) How is the low power objective lens manipulated to focus a specimen for observation under a light microscope?(Answered) State two advantages of using a coverslip when preparing a specimen for observation under a light microscope(Answered) A student drew a 6cm long diagram of a plant flower. If the actual length of the flower was 12cm, calculate the magnification of the drawing made by the student. Show your working.(Answered) State one way in which each of the following is naturally adapted to its function:
(a) Neurone.
(b) Mitochondrion(Answered) Using a microscope, a student counted 55 cells across a field of view whose diameter was 6000#mu#m. Calculate the average length of cells. Show your working.(Answered) Name the organelle that is involved in each of the following:
(a) Manufacture of lipids.
(b) Formation of lysosomes.(Answered) Why is it recommended to keep the stage of the microscope dry?(Answered) Name the part of a light microscope used to bring an image of a specimen into sharp focus(Answered)