Check WAEC GCE Biology Questions 2017 Repeated Questions
Check WAEC GCE Biology Questions
The West African Examinations Council (WAEC) is an examination board that conducts the West African Senior School Certificate Examination, for University and Jamb entry examination in West Africa countries. … In a year, over three million candidates registered for the exams coordinated by WAEC.
Check WAEC GCE Biology Questions 2017
1a)Plants take in some compounds like carbon dioxide through their leaves. They absorb some other materials such as compounds of nitrogen, phosphorus, etc., from the soil through their roots.
the transport system consists of tube like passages made up of vascular tissue. There are two types of vascular tissues in plants—xylem and phloem.
The vascular system extends from the roots through the stem and continues up to the leaves. In the leaves it is clearly seen as a pattern of veins. Water and minerals are transported from the roots upwards through the xylem tubes.
Enzyme is a substance produced by a living organism which acts as a catalyst to bring about a specific biochemical reaction.
i)all enzymes are proteins.
ii)Enzymes possess great catalytic power.
iii)Enzymes are highy specific.
iv)Enzymes show varying degree of specificities.
v)Absolute specificity where the enzyme sreact specifically with only one substrate.
Pancreatic fluid or juice contains digestive enzymes that pass to the small intestine where they help to further
break down the carbohydrates, proteins,
and lipids (fats) in the chyme. Pancreatic
juice is a liquid secreted by the pancreas,
which contains a variety of enzymes
including trypsinogen,chymotrypsinogen, elastase, carboxypeptidase, pancreatic lipase, nucleases,andamylase.Pancreatic juice is alkaline in nature due to the high concentration of bicarbonate ions. This is useful in neutralizing the acidic gastric acid, allowing for effective enzymic action.
most importantly,sun provides vitamin D which helps the body absorb the minerals calcium and phosphorus from the food that the boy eat, which is important for bone health. While milk is the main source of dietary calcium. Calcium is a major bone mineral, mandatory for bone health.
i)Photosynthesis conducted by plants is also an important part of the carbon cycle.
ii)It releases oxygen needed for breathing
iii)It serves as source of food manufacturing for human rights
iv)It provides sources for fuel through plants
v)it help to balance the ecosystem
Fungi eg zygomycota
Bacteria eg streptococcus
Viruses eg HIV
i)mimicry is a similarity of one species to another that protects one or both.
An example of this is the cuckoo bee.
ii)Camouflage is the structural adaption that enables specie s to blend with their
surroundings; allows a species to avoid
detection by predators.
i)Their legs are adapted for running
ii)They adapts the leathery forewings as
temina to provide a protective cover for the second set of wings.
iii)they evolved mandibles to bite and chew solid food.
i)It reduces the quality and quantity of the crops
ii)it reduces their productivity
iv)by the use of silos
ii)in crime detection