WASSCE 2025 BIOLOGY TRIAL *_SECTION A_* *1. (a)* Explain *briefly* how soil water gets to the leaves of a plant. *(b)* State *five* reasons for classifying organisms. *(c)* Explain *briefly* how the following structures of mammals are adapted to their functions: *(i)* veins; *(ii)* arteries. https://whatsapp.com/channel/0029VaEW2JPEawdvPSdOBG1m *2. (a) (i)* Define enzymes. *(ii)* State *five* characteristics of enzymes. 0542743763 *(b)* Describe *briefly* the role of the pancreatic juice in the digestion of carbohydrates and proteins in mammals. *(c)* A student fractured a leg, the leg was put in a cast and the student was advised to drink plenty of milk and spend some time under the sun. Explain *briefly* the reason for the instructions. *(d)* State *five* ways in which photosynthesis is of importance to humans. *3. (a) (i)* Name *three groups* of microorganisms. *(ii)* Give *one* example of each group. *(iii)* State *four* ways by which microorganisms can be controlled. *(b)* List *four* abiotic factors that affect an animal living at the bottom of the sea. *(c) (i)* List *three* human activities that may lead to extinction of species in an area. Bryson *(ii)* State *three* adverse of the extinction of a plant species on humans. *4.* In maize species, starchy grain *(GG)* is dominant to sugary grain *(gg)*. *Two* pure maize varieties were crossed, one grown from a starchy grain and the other grown from a sugary grain. https://whatsapp.com/channel/0029VaEW2JPEawdvPSdOBG1m *(a) (i)* With the aid of genetic diagram, determine the phenotype of *F1* grains. *(ii)* The *F1* grains grew into mature plants and were allowed to self pollinate. What is the expected ratio of starchy to sugary grains on the cobs borne on the *F2* plants? *(b)* If the total of *F2* grains collected is *580*, how many of these would be expected to be: *(i)* starchy; *(ii)* sugary. *_SECTION B_* *5. (a)* Describe the _Watson and Crick model of DNA_ structure. *(b)* Describe briefly the method of feeding in _Rhizopus._ *(c)* In a tabular form, outline *three* difference between *two* named classes of _Bryophyta._ *(d)* Name *three* sources of: *(i)* energy which do *not* depend on fossil fuel; *(ii)* biological fuel. *(e)* Describe the structure of the cartilage found in mammals. *(f)* In a tabular form, state *four* difference between a dicotyledonous stem and a monocotyledonous root. *_SECTION C_* _ *6. (a)* Explain *briefly* the following adaptive behaviours giving one example in each case: *(i)* mimicry; *(ii)* camouflage. *(b)* State three structural features that adapt cockroach to its habitat. *(c)* State *two* effects of pests on plants. *(d)* List *four* methods of preserving food. *(e)* List *two* applications of variation in a human society. *(f)* State *four* factors that could lead to competition in a plant population. *(g)* Explain the term _succession._ *(h)* State three disadvantages of burning vegetation before cropping