2.1 The diagram below represents the female reproductive system - NSC Life Sciences - Question 2 - 2023 - Paper 1

The process is called Fertilisation.

During fertilisation, the nucleus of the sperm fuses with the nucleus of the ovum to form a zygote. This fusion combines genetic material from both parents, leading to the formation of a diploid cell.

After fertilisation, the zygote undergoes several divisions through mitosis, creating a solid ball of cells known as the morula. The morula then develops into a blastocyst as fluid fills the interior, preparing for implantation into the uterine wall, where it can develop further.

1. The cervix is muscular and can expand, allowing for easier passage of sperm while providing a barrier to protect against infections.
2. The cervical mucus changes in viscosity, becoming less thick during ovulation to facilitate sperm movement while offering protection during non-fertile phases.

The prostate gland secretes a fluid that is alkaline, which neutralizes the acidic environment of the vagina, thus protecting sperm and enhancing their motility.

One function of FSH is to stimulate the development of ovarian follicles in females.

One other hormone is LH (Luteinizing Hormone).

An under secretion of LH can prevent ovulation from occurring, as it is essential for triggering the release of the ovum from the follicle. This results in no egg being available for fertilisation, causing infertility.

If ovarian follicles do not mature properly, it can lead to a lack of ovulation or anovulatory cycles, meaning no egg is released. Without the presence of an egg, fertilisation cannot occur, and there will be no zygote to implant, resulting in reduced implantation rates.

The type of fertilisation is external fertilisation.

Millions of gametes are released to increase the chances of fertilisation, as many may not reach the other gamete due to predation or environmental factors like water currents.

Reproduction in frogs is an example of ovipary because the embryos develop inside an egg, outside the female's body, as the eggs are laid and develop in the aquatic environment.

1. Part A has ducts that release secretions externally, not directly into the bloodstream.
2. It secretes sweat, which is a product that is excreted rather than a hormone.

Skin receptors detect temperature changes and send signals to the hypothalamus, which triggers physiological responses such as sweating or vasodilation to maintain a stable internal body temperature.

Structure B dilates on a hot day to increase blood flow to the skin surface, promoting heat loss through convection and evaporation, which helps lower body temperature.

The organ of Corti is located in the cochlea.

To find the percentage increase, use the formula:

$ext{Percentage Increase} = \frac{(130000 - 85000)}{85000} \times 100 = 52.94\%$.

One reason for the increase may be extended exposure to loud sounds, possibly due to increased factory activity or lack of protective measures.

Damage to the auditory nerve can prevent sound impulses from being transmitted to the brain, meaning that sound will not be interpreted, which results in hearing loss.

Please refer to the accompanying data table to construct the bar graph, ensuring correct labeling and scale as indicated.