Get premium membership and access questions with answers, video lessons as well as revision papers.
Males have two dissimilar chromosomes X and Y/heterogametic;
Females have two similar chromosomes X and X/homogametic;
Male gamete/sperms have either X or Y chromosome, while all ova have X chromosome;
If a sperm with X fuses with an ovum a female is formed and if a sperm with Y fuses with an ovum a make is formed;
Sickle-cell trait is heterozygous while sickle cell anaemia is a homozygous condition;
People with sickle cell trait are resistant to malaria; because the plasmodium cannot survive in sickle shaped cells.
adhixbelly answered the question on September 20, 2017 at 09:40
- (a) Describe the mechanism of gaseous exchange in plants through the lenticels. (b) Explain each of the following:the tracheoles lack spiral bands of chitin;the floor of the mouth...(Solved)
(a) Describe the mechanism of gaseous exchange in plants through the lenticels. (b) Explain each of the following:the tracheoles lack spiral bands of chitin;the floor of the mouth...
Date posted: September 20, 2017. Answers (1)
- (a) State four characteristics of fruits dispersed by animals. (b) State two roles of each of the following hormones in menstruation:l (i) luteinising hormone (ii) oestrogen.(Solved)
(a) State four characteristics of fruits dispersed by animals. (b) State two roles of each of the following hormones in menstruation: (i) luteinising hormone (ii) oestrogen.
Date posted: September 20, 2017. Answers (1)
- Why is a burning charcoal stove in a poorly ventilated room likely to cause death of the inhabitants?(Solved)
Why is a burning charcoal stove in a poorly ventilated room likely to cause death of the inhabitants?
Date posted: September 20, 2017. Answers (1)
- Name three types of transpiration(Solved)
Name three types of transpiration
Date posted: September 19, 2017. Answers (1)
- a)What is meant by seed dormancy? (b)state three causes of seed dormancy?(Solved)
a)What is meant by seed dormancy? (b)state three causes of seed dormancy?
Date posted: September 19, 2017. Answers (1)
- Outline types staining process(Solved)
Outline types staining process
Date posted: September 18, 2017. Answers (1)
- What is Biology?(Solved)
What is Biology?
Date posted: September 18, 2017. Answers (1)
- What is a gene?(Solved)
What is a gene?
Date posted: September 18, 2017. Answers (1)
- What type of membrane is the cell membrane in terms of permeability?(Solved)
What type of membrane is the cell membrane in terms of permeability?
Date posted: September 18, 2017. Answers (1)
- What is the name of an RNA sequence that codifies one amino acid?(Solved)
What is the name of an RNA sequence that codifies one amino acid?
Date posted: September 18, 2017. Answers (1)
- Where does respiration take place in a cell? (Solved)
Where does respiration take place in a cell?
Date posted: September 18, 2017.
- State the adaptations of plants which enable them to reduce water loss(Solved)
State the adaptations of plants which enable them to reduce water loss
Date posted: September 18, 2017. Answers (1)
- State the structural differences between xylem vessels and sieve tubes(Solved)
State the structural differences between xylem vessels and sieve tubes
Date posted: September 18, 2017. Answers (1)
- Explain the environmental factors that affect rate of transpiration in plants(Solved)
Explain the environmental factors that affect rate of transpiration in plants
Date posted: September 18, 2017. Answers (1)
- Explain the structural factors that affect the rate of transpiration in plants(Solved)
Explain the structural factors that affect the rate of transpiration in plants
Date posted: September 18, 2017. Answers (1)
- Explain the uptake of mineral salts by plants(Solved)
Explain the uptake of mineral salts by plants
Date posted: September 18, 2017. Answers (1)
- Explain the forces that make water and mineral salts move through a plant(Solved)
Explain the forces that make water and mineral salts move through a plant
Date posted: September 18, 2017. Answers (1)
- Describe the movement of water from the soil to the leaves of a tall plant(Solved)
Describe the movement of water from the soil to the leaves of a tall plant
Date posted: September 18, 2017. Answers (1)
- Why do flowering plants need water?(Solved)
Why do flowering plants need water?
Date posted: September 18, 2017. Answers (1)
- State the role of vitamin K to the human body(Solved)
State the role of vitamin K to the human body
Date posted: September 16, 2017. Answers (1)