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- It has chondrionic villis to increase surface area for excahgne of materials
- Has thin epithelium for rapid exchange of exchanged substances
- Has counter current flow of foetal and maternal blood to enhance speed diffusion gradient.
- Highly vascularised (dense network of capillaries) for faster transport of exchanged material
Kavungya answered the question on June 17, 2019 at 10:43
- Explain why monocotyledons plants do not undergo secondary thickening.(Solved)
Explain why monocotyledons plants do not undergo secondary thickening.
Date posted: June 17, 2019. Answers (1)
- State the role of the vascular cambium in plant growth and development.(Solved)
State the role of the vascular cambium in plant growth and development.
Date posted: June 17, 2019. Answers (1)
- State the biological importance of ecdysis in arthropods.(Solved)
State the biological importance of ecdysis in arthropods.
Date posted: June 17, 2019. Answers (1)
- What is the role of the following to a germinating seed? (i) Oxygen(ii) Cotyledons(Solved)
What is the role of the following to a germinating seed?
(i) Oxygen
(ii) Cotyledons
Date posted: June 17, 2019. Answers (1)
- State one disadvantage of exoskeleton in insects.(Solved)
State one disadvantage of exoskeleton in insects.
Date posted: June 17, 2019. Answers (1)
- The cells shown below were obtained from different parts of a young root tip:
Give the name of the zone from which each cell was obtained...(Solved)
The cells shown below were obtained from different parts of a young root tip:
Give the name of the zone from which each cell was obtained A, B and C
Date posted: June 17, 2019. Answers (1)
- An experiment was set-up as shown in the diagram below:-
(a) Suggest the possible aim of this experiment
(b) Account for the observation at the end of...(Solved)
An experiment was set-up as shown in the diagram below:-
(a) Suggest the possible aim of this experiment
(b) Account for the observation at the end of the experiment
Date posted: June 17, 2019. Answers (1)
- State the location of Vascular cambium.(Solved)
State the location of Vascular cambium.
Date posted: June 17, 2019. Answers (1)
- State the importance of moulting in insects.(Solved)
State the importance of moulting in insects.
Date posted: June 17, 2019. Answers (1)
- Describe the behavioural adaptations of animals to temperature(Solved)
Describe the behavioural adaptations of animals to temperature
Date posted: June 17, 2019. Answers (1)
- Study the genetic chart below showing the inheritance of the gene responsible for haemophilia
in a family.
a) Write the genotype of individuals A, B, F
b) A...(Solved)
Study the genetic chart below showing the inheritance of the gene responsible for haemophilia
in a family.
a) Write the genotype of individuals A, B, F
b) A member of this family labelled F marries a haemophiliac male. What will be the phenotypic
ratio of the offspring? Show your workings
c) Other than the condition stated above, state any other two common genetic disorders that
result from gene mutation.
Date posted: June 17, 2019. Answers (1)
- i)Identify the nucleic acid whose base sequence is shown below:
G-A-C-U-A-G-A-C-G
ii) Give a reason for your answer in c (i) above
iii) If the nucleic acid was...(Solved)
i)Identify the nucleic acid whose base sequence is shown below:
G-A-C-U-A-G-A-C-G
ii) Give a reason for your answer in c (i) above
iii) If the nucleic acid was involved in protein synthesis, how many amino acids would be
present in the protein synthesized? Give a reason
Date posted: June 17, 2019. Answers (1)
- In a certain bird species, red flight feathers is controlled by gene R while white flight feathers is
controlled by gene r. The heterozygous condition Rr...(Solved)
In a certain bird species, red flight feathers is controlled by gene R while white flight feathers is
controlled by gene r. The heterozygous condition Rr results into pink flight feathers. The two
genes are also sex linked and transmitted on x-chromosome.
a) By use of fusion lines, find the genotypes of across between a male with pink flight
feathers and a female with white flight feathers
b) Which type of dominance is illustrated here?
Date posted: June 17, 2019. Answers (1)
- A section of a DNA strand contains the following sequence CGGATAC
(a) Write the; (i) Complementary DNA strand
(ii) MRNA strand
(b) Name the site for protein synthesis...(Solved)
A section of a DNA strand contains the following sequence CGGATAC
(a) Write the; (i) Complementary DNA strand
(ii) MRNA strand
(b) Name the site for protein synthesis in a cell
Date posted: June 17, 2019. Answers (1)
- Name two mutagens(Solved)
Name two mutagens
Date posted: June 17, 2019. Answers (1)
- Name a genetic disorder due to gene mutation that affects the malpighian layer of the
skin in man.(Solved)
Name a genetic disorder due to gene mutation that affects the malpighian layer of the
skin in man.
Date posted: June 17, 2019. Answers (1)
- Explain why prophase 1 of meiosis contributes towards genetic variation in living
organisms.(Solved)
Explain why prophase 1 of meiosis contributes towards genetic variation in living
organisms.
Date posted: June 17, 2019. Answers (1)
- Explain why growth of long hair on the pinnae of the ears in human occurs in males only(Solved)
Explain why growth of long hair on the pinnae of the ears in human occurs in males only
Date posted: June 17, 2019. Answers (1)
- In a certain breeding experiment, a plant species with red flowers was selfed. It produced 119
red flowered and 41 white flowered offsprings.
(a) Using letter R...(Solved)
In a certain breeding experiment, a plant species with red flowers was selfed. It produced 119
red flowered and 41 white flowered offsprings.
(a) Using letter R to represent allele for the red flowers, state the genotype of the red flowered
parent plant
(b) Determine the phenotypic ratio of red and white flowered plants. Show your working
Date posted: June 17, 2019. Answers (1)
- State the meaning of the following terms giving an example in each case:
(a) Sex-linked genes
(b) Multiple alleles(Solved)
State the meaning of the following terms giving an example in each case:
(a) Sex-linked genes
(b) Multiple alleles
Date posted: June 17, 2019. Answers (1)