Chapter 2.3 Fertilisation ✓

Question 1

Define fertilisation

Answer 1

The fusion of haploid male and female gametes during sexual reproduction to produce a diploid zygote

Question 2

Why does fertilisation lead to an increase in variation of offspring?

Answer 2

Because it involves the fusing of two haploid cells from two different parents to form one diploid cell (the zygote)

Question 3

Define apoptosis

Answer 3

Apoptosis (or programmed cell death) is a programmed series of events that leads to cell death

Question 4

Why is cell death by apoptosis a vital process?

Answer 4

Because it is essential for development and the shaping of organisms and tissues e.g. apoptosis allows tadpoles to lose its tail to become a frog

Question 5

What are the inputs and outputs of meiosis?

Answer 5

Inputs: Starts with a diploid cell with replicated DNA.
Output: Produces four genetically unique haploid daughter cells.

Question 6

What is the role of the sex chromosome?

Answer 6

It determines the sex of an organism.
-Females sex chromosome are XX whereas male sex chromosome are XY

Question 7

Explain why offspring produced from asexual reproduction resemble their parents whereas offspring produced from sexual reproduction are different from their parents?

Answer 7

Because in sexual reproduction two parents are involved, a male and a female, but in asexual only one parent is involved and there is no fusion of a male and female gamete.

Question 8

Is the process of apoptosis beneficial to an organism? Explain

Answer 8

-Yes its beneficial because it maintains homeostasis and proper development.
-It removes damaged, old or unnecessary cells, preventing diseases like cancer.
-In development, apoptosis shapes structures (e.g. tadpole tail loss, finger separation in embryos)
-It also plays a role in immune system regulation by eliminating harmful or unneeded cells.