Question 1

What is fertilisation in the context of Edexcel International A Levels Biology?

Accepted Answer

Fertilisation is the process by which male and female gametes (sperm and egg cells) fuse to form a zygote. This is a crucial step in sexual reproduction, leading to the development of a new organism. In the Edexcel International A Levels Biology curriculum, fertilisation is studied as part of the broader topics of cells, development, and biodiversity.

Question 2

How does fertilisation contribute to genetic diversity?

Accepted Answer

Fertilisation contributes to genetic diversity by combining genetic material from two parents. Each gamete carries half the genetic information from its parent, and when they fuse, they create a unique genetic combination in the zygote. This genetic variation is essential for the survival and adaptation of species, as it increases the likelihood of individuals possessing traits that can withstand environmental changes.

Question 3

What are the stages of fertilisation in human biology?

Accepted Answer

In human biology, fertilisation involves several stages: 1) Sperm capacitation, where sperm undergo physiological changes to penetrate the egg; 2) Sperm binding to the zona pellucida of the egg; 3) Acrosome reaction, allowing the sperm to penetrate the egg; 4) Fusion of sperm and egg membranes; and 5) Formation of the zygote. These stages ensure successful fertilisation and are key topics in the Edexcel International A Levels Biology syllabus.

Question 4

Why is the study of fertilisation important in biodiversity and conservation?

Accepted Answer

Studying fertilisation is crucial for understanding biodiversity and conservation because it underpins the reproductive success and genetic variation of species. By understanding fertilisation, biologists can develop strategies to conserve endangered species, manage breeding programs, and maintain genetic diversity, which is vital for ecosystem resilience and adaptability.

Question 5

What are the differences between internal and external fertilisation?

Accepted Answer

Internal fertilisation occurs inside the body of the organism, as seen in mammals, birds, and reptiles, providing a protected environment for the developing zygote. External fertilisation occurs outside the body, common in aquatic animals like fish and amphibians, where eggs and sperm are released into the water. Each method has evolutionary advantages and is studied in the context of reproductive strategies in the Edexcel International A Levels Biology curriculum.

Fertilisation

Short Notes - Fertilisation

Study Notes & Exam Tips

Fertilisation — frequently asked questions