Fertilisation in humans

Define gametes, identify the male and female gametes, and state their role in reproduction.
Describe the process of fertilisation, including the journey of the sperm and egg, where they typically meet, and the immediate result (formation of an embryo).
Explain the process of implantation, where it occurs, and what happens to the embryo after it has implanted.

Babies are created by the combination of genetic material from both a mother and a father. This process begins during reproduction when specialised cells from each parent join together.
Gametes are reproductive cells.
The male gamete is the sperm cell, and the female gamete is the egg cell.
When a sperm cell and an egg cell meet and combine their genetic material, it’s called fertilisation. Fertilisation is the first step in forming a new organism.

Each month, one egg cell is released from a female’s ovary and travels down the oviduct (fallopian tube).
Cilia (tiny hair-like structures) line the oviduct and help move the egg towards the uterus.
During sexual intercourse, the male releases sperm into the female’s vagina.
The sperm then swim up through the uterus and into the oviduct in search of the egg.
When a sperm cell meets an egg cell in the oviduct, fertilisation occurs. The head of the sperm enters the egg, combining their genetic material.
The fertilised egg then divides several times, forming a cluster of cells known as an embryo.

The embryo travels to the uterus and attaches itself to the lining. This is called implantation.
Once implanted, the embryo continues to grow and develop, eventually becoming a baby.

Gametes: Reproductive cells (sperm in males, egg in females).
Sperm cell: The male gamete.
Egg cell: The female gamete.
Fertilisation: The joining of a sperm cell and an egg cell to combine their genetic material.
Genetic material: The material (DNA) from each parent that is combined during fertilisation.
Oviduct (Fallopian tube): The tube where the egg travels from the ovary to the uterus, and where fertilisation usually occurs.
Embryo: The early stage of development of a new organism, formed from a fertilised egg cell.
Implantation: The process where the embryo attaches itself to the lining of the uterus.
Uterus (Womb): The organ where the embryo implants and develops into a baby.

Investigate the key stages of embryonic and fetal development that occur in the uterus after successful implantation.
Research factors that can affect human fertility or the success of fertilisation and implantation.