Get premium membership and access questions with answers, video lessons as well as revision papers.
a) A – gill filament B – gill rakers C – gill arch/ bar
(b) Maintain a steep concentration gradient across the respiratory surface; facilitating maximum gaseous exchange between
the water flowing over the gills to the blood in the gills
c) (i) Are numerous to increase the surface area for gaseous exchange, for faster diffusion of respiratory gases
(ii) Thin walled for faster diffusion of respiratory gases
(iii) Highly vascularized to transport the respiratory gases for faster diffusion of respiratory gases
Moist to dissolve respiratory gases for faster diffusion of respiratory gases
sharon kalunda answered the question on May 27, 2019 at 05:45
- A group of students set up an experiment to demonstrate a certain process as shown below.
After 10 minutes the students carried out iodine test inside...(Solved)
A group of students set up an experiment to demonstrate a certain process as shown below.
After 10 minutes the students carried out iodine test inside and outside the visiking tubing.
a) state two roles of the process being investigated in animals.
b) account for the results expected in the experiment above.
c)i) What is the importance of plasma membrane in active transport.
ii) Give one similarity between osmosis and active transport.
Date posted: May 27, 2019. Answers (1)
- Name the plant organs in which meiosis take place(Solved)
Name the plant organs in which meiosis take place
Date posted: May 27, 2019. Answers (1)
- Haemophilia is a genetic condition transmitted through a recessive gene linked to X chromosome. The normal gene may
be represented by XH
i) What is the genotype...(Solved)
Haemophilia is a genetic condition transmitted through a recessive gene linked to X chromosome. The normal gene may
be represented by XH
i) What is the genotype of the haemophilic female?.
ii) A woman who is a carrier for the haemophilia gene marries a normal man. Work out the phenotypic ratio for their
offspring.
iii) Haemophilia is more common in males than in females. Explain this phenomenon.
Date posted: May 27, 2019. Answers (1)
- The diagram below is a functional unit of a mammalian kidney
a) Name the process that occurs in
L
P
b) (i) state the structural difference between K...(Solved)
The diagram below is a functional unit of a mammalian kidney
b) Name the process that occurs in
L
P
b) (i) state the structural difference between K and M
(ii)How does the structural difference above help in the process that occurs in L
Date posted: May 27, 2019. Answers (1)
- Name the parts of a mammalian ear which carry out the following function (i) balance and posture (ii) hearing(Solved)
Name the parts of a mammalian ear which carry out the following function
i) balance and posture
ii) hearing
Date posted: May 24, 2019. Answers (1)
- A boy could clearly read a book placed 10cm away but could not identify his friend 10 metres away
a) What eye defect was he suffering...(Solved)
A boy could clearly read a book placed 10cm away but could not identify his friend 10 metres away
a) What eye defect was he suffering from)
b) State how the defect can be corrected
Date posted: May 24, 2019. Answers (1)
- The diagram represents a stage of growth and development of two different plants
With reasons identify the types of germination shown by Plant A and B(Solved)
The diagram represents a stage of growth and development of two different plants
With reasons identify the types of germination shown by Plant A and B
Date posted: May 24, 2019. Answers (1)
- What is meant by the following terms
a) Habitat
b) Biomass(Solved)
What is meant by the following terms
a) Habitat
b) Biomass
Date posted: May 24, 2019. Answers (1)
- The number and distribution of stomata of three different leaves are shown in the table below
Suggest the possible habitat of the plant from which the...(Solved)
The number and distribution of stomata of three different leaves are shown in the table below
Suggest the possible habitat of the plant from which the leaves were obtained
A
B
Date posted: May 24, 2019. Answers (1)
- Name the blood vessel that connects arteries to veins(Solved)
Name the blood vessel that connects arteries to veins
Date posted: May 24, 2019. Answers (1)
- Name the organelles that would be most likely found in large numbers in cells that perform the functions below.
a) A cell in the ileum that...(Solved)
Name the organelles that would be most likely found in large numbers in cells that perform the functions below.
a) A cell in the ileum that actively takes in glucose
b) A cell in the liver that breaks down foreign bodies
Date posted: May 24, 2019. Answers (1)
- State the function of the Node of ranvier structures in neurone.(Solved)
State the function of the Node of ranvier structures in neurone.
Date posted: May 24, 2019. Answers (1)
- High temperature stops enzyme action.Explain.(Solved)
High temperature stops enzyme action.Explain.
Date posted: May 24, 2019. Answers (1)
- Lack of magnesium leads to yellowing of leaves in plants.Explain.(Solved)
Lack of magnesium leads to yellowing of leaves in plants.Explain.
Date posted: May 24, 2019. Answers (1)
- The thyroid glands swell in some individuals.Explain.(Solved)
The thyroid glands swell in some individuals.Explain.
Date posted: May 24, 2019. Answers (1)
- What is the biological importance of denitrification(Solved)
What is the biological importance of denitrification
Date posted: May 24, 2019. Answers (1)
- A couple gave birth to children with all types of blood groups. Suggest the possible genotypes of the parents(Solved)
A couple gave birth to children with all types of blood groups. Suggest the possible genotypes of the parents
Date posted: May 24, 2019. Answers (1)
- The diagram below show an instrument used in the Biology laboratory
Name the instrument and state its functions
Name
Function(Solved)
The diagram below show an instrument used in the Biology laboratory
Name the instrument and state its functions
Name
Function
Date posted: May 24, 2019. Answers (1)
- An experiment was carried out to investigate haemolysis of human red blood cells. The red blood cells were placed in different concentration of sodium chloride...(Solved)
An experiment was carried out to investigate haemolysis of human red blood cells. The red blood cells were placed in different concentration of sodium chloride solution. The percentage of haemolysed cells was determined. The results were as shown in the table below.
a) i) On the grid provided, plot a graph of haemolysed red blood cells against salt concentration.
ii)At what concentration of salt solution was the proportion of haemolysed cell equal to non-haemolysed cells?
iii) State the percentage of cells haemolysed at salt concentration of 0.45%.
b) Account for the results obtained at:
i) 0.33 percent salt concentration.
ii) 0.48 per cent salt concentration.
c) What would happen to the red blood cells if they were placed in 0.50 percent salt solution?
d) Explain what would happen to onion epidermal cells if they were placed in distilled water.
Date posted: May 24, 2019. Answers (1)
- The diagram below represents a food web in a certain ecosystem.
a) Name the trophic level occupied by each of the following:
i) Caterpillar .
ii) Small...(Solved)
The diagram below represents a food web in a certain ecosystem.
a) Name the trophic level occupied by each of the following:
i) Caterpillar .
ii) Small insects .
b) From the food web, construct two food chains which end with lizards as tertiary consumer.
c) i) Which organisms have the least biomass in this ecosystem?
ii) Explain the answer in c(i) above.
Date posted: May 24, 2019. Answers (1)