Get premium membership and access questions with answers, video lessons as well as revision papers.
- Diffusion gradient which refers to the difference in concentration of molecules between the region of high concentration and the region of low concentration. Increasing the concentration gradient causes an increase in rate of diffusion and vice versa.
A great diffusion gradient between two points increases the rate of diffusion. Increasing diffusing molecules increases the diffusion gradient between corresponding regions thus increasing the rate of diffusion. A low diffusion gradient on the other hand decreases the rate of diffusion.
-Surface area to volume ratio .is the ratio of total surface area exposed by an organism compared to its body volume. Small sized living organisms have a large surface area to volume ratio. The larger the surface area to volume ratio ,the high the rate of diffusion and vice versa. Small organisms like amoeba and paramecium can hence rely on diffusion for transport of substances into and within its body and removal of waste products
- Thickness of membranes. Molecules take longer to diffuse across thick membranes than across thin membranes hence the thin the membrane the higher the rate of diffusion.
-Temperature. Increasing temperature increases the kinetic energy of diffusing molecules making them
to spread faster. Increasing temperature increases the rate of diffusion and vice versa
-Size of molecules/molecular weight.Small sized molecules/molecules of low molecular weight move/diffuse faster hence the rate of diffusion is high where the molecules involved are small or have low molecular weight and vice versa.
simiyu kelly answered the question on September 15, 2017 at 12:14
- a) What is active transport? (b) State the factors affecting active transport(c) Why is oxygen important in the process of active transport?(Solved)
a. What is active transport?
b. State the factors affecting active transport
c. Why is oxygen important in the process of active transport?
Date posted: September 15, 2017. Answers (1)
- (a) What is osmosis? (b) Explain the roles of osmosis in living organisms(Solved)
a. What is osmosis?
b. Explain the roles of osmosis in living organisms
Date posted: September 15, 2017. Answers (1)
- a) What is diffusion? (b) State the factors affecting diffusion (c) Explain the roles of diffusion in living organisms gaseous exchange (d) Suggest an experiment to demonstrate diffusion(Solved)
a. What is diffusion?
b. State the factors affecting diffusion
c. Explain the roles of diffusion in living organisms gaseous exchange
d. Suggest an experiment to demonstrate diffusion
Date posted: September 15, 2017. Answers (1)
- Explain the properties of cell membrane(Solved)
Explain the properties of cell membrane.
Date posted: September 15, 2017. Answers (1)
- Describe the structure of cell membrane(Solved)
Describe the structure of cell membrane
Date posted: September 15, 2017. Answers (1)
- a) What is magnification? (b)Give the formula used to calculate magnification in a light microscope(Solved)
a. What is magnification?
b. Give the formula used to calculate magnification in a light microscope
Date posted: September 15, 2017. Answers (1)
- a) What is a microscope? (b)Name the types of microscopes. (c) State the purpose of using a light microscope. (d) Explain the procedure followed when using a...(Solved)
a. What is a microscope?
b. Name the types of microscope
c. State the purpose of using a light microscope
d. Explain the procedure followed when using a microscope
e. State the precautions that are necessary when handling a microscope
Date posted: September 15, 2017. Answers (1)
- a) Define the term cell (b) What is cell biology?(Solved)
a. Define the term cell
b. What is cell biology?
Date posted: September 15, 2017. Answers (1)
- a) What is a species? (b) Name the major kingdoms used in classification(Solved)
a. What is a species?
b. Name the major kingdoms used in classification
Date posted: September 15, 2017. Answers (1)
- 1. (a) what is classification? (b) List the external features used to classify plants (c) List the external features used to classify animals...(Solved)
a. What is classification?
b. List the external features used to classify plants
c. List the external features used to classify animals
d. Give the reasons why classification is important
e. Name the taxonomic units of classification in descending order
Date posted: September 15, 2017. Answers (1)
- 1. (a) What is a hand lens? (b) How is a hand lens used? (c) When is a hand lens used? (Solved)
a. What is a hand lens?
b. How is a hand lens used?
c. When is a hand lens used?
Date posted: September 15, 2017. Answers (1)
- State the characteristics of living organisms.(Solved)
State the characteristics of living organisms.
Date posted: September 15, 2017. Answers (1)
- Explain the importance of biology.(Solved)
Explain the importance of biology.
Date posted: September 15, 2017. Answers (1)
- List the branches of biology.(Solved)
List the branches of biology.
Date posted: September 15, 2017. Answers (1)
- Define Biology.(Solved)
Define Biology.
Date posted: September 15, 2017. Answers (1)
- Describe how herbaceous plants obtain their support?(Solved)
Describe how herbaceous plants obtain their support?
Date posted: September 13, 2017. Answers (1)
- How are female parts of wind pollinated flowers adapted to perform their function?(Solved)
How are female parts of wind pollinated flowers adapted to perform their function?
Date posted: September 13, 2017. Answers (1)
- (a)Define nondisjunction? (b) Name two genetic disorders of the blood.(Solved)
(a) Define nondisjunction?
(b) Name two genetic disorders of the blood.
Date posted: September 13, 2017. Answers (1)
- Give three effects of over secretion of adrenaline?(Solved)
Give three effects of over secretion of adrenaline?
Date posted: September 13, 2017. Answers (1)
- What are the roles of each of the following on transmission of impulses:(i)Nodes of Ranvier (ii)Myelin Sheath (Solved)
What are the roles of each of the following on transmission of impulses:
i)Nodes of Ranvier
ii)Myelin Sheath
Date posted: September 13, 2017. Answers (1)