1. The diagram below shows the mechanism of action of a hormone.
(a) (b) (c) (d) (e)
Label hormone X and enzyme Y. [2] State two differences between a target cell and non-target cell. [2] Name two examples of target cells or tissues. [2] Explain why hormone x cannot get across the plasma membrane easily. [2] Explain how a fast production of glycogen can be accomplished. [2]
2. Five tests were carried out on a species of plant to induce flowering by varying the period of light and flashing different types of light during the dark period. The results are as shown below.
(a) (b) (c) (d) (e)
Is the plant a short- or long-day plant? Explain. [2] Describe the effects of flashing different types of light during dark period. [3] State the effect of flashing white light during the dark period of a long-day plant. [1] Which form of phytochrome is involved in the plant used in this test? Explain. [2] How does phytochrome explain the effects of the flashing of various lights in the above test? [2]
Pg 110 pelangi 3.
The diagram below shows the change in shape of the foetus from the time it is formed to become an adult.
(a) (b) (c) (d)
What type of pattern of growth is shown? Explain. [3] Why is human development also considered to be limited growth?[2] Why are invertebrates considered to have unlimited growth? [2] Give an example of an organism with intermittent growth. Explain why it has such growth. [3] Pg 163 pelangi
4.
5.
a) State one function for each of the following cells.[5] (i) macrophage (ii) T helper cell (iii) T cytotoxic cell (v) plasma cell Page 244 p
(iv) T suppressive cell
The diagram below shows the life cycle of malaria parasite.
(a) Describe how the malarial parasite is normally transmitted from an infected person to an uninfected person. [2] (b) Explain why malaria is restricted to the tropics. [2] (c) What are the effects on the body of the presence of malarial parasites in red blood cells? [3] (d) Explain why it has proved difficult to develop a vaccine for malaria. [3]
6.
The diagram shows a bacterium that causes TB.
(a) (i) Name the bacterium that cause TB. [1] (ii) Describe how TB is transmitted from infected to uninfected people. [2] (b) Patients who suffer from TB are treated with combination of three or four antibiotics for up to a year. Explain. [3] (c) Why India and African countries have more TB cases compared to developed countries? [4] Pg 275 p 7. The diagram below shows the microscopic structure of the alveoli and surrounding pulmonary capillaries.
(a) (i) Name the two types of cells P and Q found in the alveolar wall. (ii) State the function of P and Q. (b) (i) Name the structure labelled R. (ii) State the function of R. (c) State one function of S found in vessel T.
Essay questions: 1. (a) With the aid of a diagram, show the arrangement of the extra-embryonic membranes in mammalian embryos. (b) Describe the development of the mammalian embryo from the zygote stage to the formation of the extra-embryonic membranes. State the functions of theses membranes. Pg 227 sasbadi 2. Explain why smallpox has been eradicated successfully but not tuberculosis (TB). -smallpox caused by one strain of virus -vaccine for smallpox very effective in producing long-term immunity -TB caused by Mycobacterium tuberculosis, of which many strains are drug resistant -vaccination for TB not as long-lasting especially for people with weakened immune systems (HIV infected people) -TB patients do not complete treatment, so they may harbor drug-resistant forms of the bacteria -disease spreads easily in congested living conditions due to poverty, wars, natural disasters 3.