Chapter 24 - Sexual & Asexual Reproduction

Question 1

Asexual reprodution in bacteria

Answer 1

1. Bacteria are single-celled
2. Split by binary fission
3. Duplicates chromosomes
4. Chromosomes segregate to opposite sides
5. Ingrowth of cell membeane occurs

Question 2

Asexual reproduction in fungi

Answer 2

1. Reproduce by forming spores
2. Spores geminate to form hypha
3. All hyphae together are jnown as mycelium
4. Some hyphae form arial parts with sporangium
5. Many spires form in sporngium
6. Sporangium burst open to release diploid spores

Question 3

Asexual reproduction in potatoes

Answer 3

1. Have auxiliary buds (eyes)
2. New shoots and roots grow from the eyes
3. Roots grow down and shoots form leaves
4. New tubers form when the tips swell as the stored nutrients translocate from leaves diwnwards

Question 4

Define sexual reproduction

Answer 4

Production of new generation of same species by two parents and involve formation of gametes and fertilistion occurs

Question 5

Name 5 advantages of asexual reproduction

Answer 5

1. Simple and fast
2. Only one parent is needed
3. Offspring is identical
4. Rapid spreading can crowd out competition
5. No need for agents for plants

Question 6

Name 5 disadvantages of asexual reproduction

Answer 6

1. Genetically identical
2. diseases spread rapidly
3. All offspring may be affected by same disease
4. overcrowding may occur
5. If parent is not well adapt, offspring will not be adapted to surrounding

Question 7

Name 4 advantages of sexual reproduction

Answer 7

1. Leads to variations
2. Better chance of survival
3. Seeds are dispersed to other areas
4. Evolution of new species cn occur

Question 8

Name 5 disadvantages of sexual reproduction

Answer 8

1. Two parents are required
2. Young may be vulnerable
3. Other agents are needed
4. Fertilisation may not happen
5. Much pollen is wasted

Question 9

What is artificial propagation

Answer 9

Produces by human efforts and not originating naturally

Question 10

Principle of artificial propagation of plant by cuttings

Answer 10

1. A part of plant is removed
2. Plant hormones are used
3. Auxins stimulate root growth
4. Place cutting into water to form roots

Question 11

Principles of artificial propagation by micropropagation

Answer 11

1. Take small piece of growing tip
2. Sperarate the cells
3. Places cell in culture solution
4. Solution must contain sucrose, amino acid, vitamins and auxins
5. All conditions must be sterile and controlled
6. Small plantlet is produced

Question 12

Name 7 advantages of propagation

Answer 12

1. Genetically identical
2. Rapid production
3. Produced any time of the year
4. Market cn be created for exotic plants
5. Plants can be stored for long periods
6. Diseases can be avoided
7. Is a more practical method

Question 13

Name 4 disadbantages of propagation

Answer 13

1. Genetically identical and disease may kill them
2. Expensive instruments
3. Conditions must be sterile
4. Is time consuming

Question 14

Define asexual reproduction

Answer 14

Production of new generation of same species by one parent which does not involve formation of gametes or fertilistion