3a- reproduction

Question 1

Asexual Reproduction:

Answer 1

Only one parent is needed. Offspring are genetically identical (clones). Examples: Bacteria, plants like strawberry runners.

Question 2

Sexual Reproduction:

Answer 2

Two parents contribute genetic material. Offspring show genetic variation. Examples: Humans, flowering plants.

Question 3

Asexual Reproduction adv and dis:

Answer 3

Advantages: Faster, no need for a mate, produces large numbers of offspring quickly.

Disadvantages: No genetic variation, making species vulnerable to environmental changes.

Question 4

Sexual Reproduction adv and dis:

Answer 4

Advantages: Genetic variation increases chances of survival in changing environments.

Disadvantages: Slower, requires two parents, fewer offspring produced.

Question 5

What is the structure and function of the reproductive organs in humans:

Male:

Answer 5

Testes produce sperm and testosterone.

Sperm duct and urethra transport sperm.

Penis delivers sperm into the female reproductive system.

Question 6

What is the structure and function of the reproductive organs in humans:

Female:

Answer 6

Female:

Ovaries produce eggs and oestrogen.

Fallopian tubes transport eggs to the uterus.

Uterus provides a site for embryo development.

Vagina receives sperm and acts as the birth canal.

Question 7

How does fertilization occur in humans?

Answer 7

Fertilization occurs when a sperm cell fuses with an egg cell in the fallopian tube, forming a zygote. The zygote divides and develops into an embryo, which implants in the uterus.

Question 8

What is the difference between internal and external fertilization?

Answer 8

Internal Fertilization: Occurs inside the female’s body (humans, mammals). Higher survival rate due to protection inside the body.

External Fertilization: Occurs outside the female’s body (fish, amphibians). Large numbers of gametes are released, but survival rates are lower.

Question 9

Practical: Investigating Asexual Reproduction in Plants

Answer 9

Method:

Take cuttings from a plant stem.

Place the cuttings in soil or water.

Keep them in a warm environment with sunlight.

Observation:

Positive Result: Roots grow from the cuttings, indicating successful asexual reproduction.

Negative Result: No root growth indicates that conditions were not suitable.