Fertilisation-and-implantation-PPT.pptxp

Fertilization

1. Keywords: Fertilisation Cilia Ejaculation Embryo Implantation State what is meant by fertilsation . Describe the processes of sexual intercourse and fertilisation . Describe causes of low fertility in males and females. Fertilisation and implantation! Learning Objective: What happens during fertilisation? DO NOW : What do you think is meant by the keyword fertilisation ? KS3 Activate Science

2. RECALL TASK : Match the keyword to the definition. PENIS VAGINA SPERM DUCT OVIDUCT TESTES OVARIES Contains eggs. Produces sperm. Carries an egg to the uterus. Carries sperm out of the body. Carries sperm to the penis. Receives sperm during sexual intercourse.

3. What can you remember? RECALL: Reproductive systems A B C D E 1 2 3 4 5 6 7

4. These are the main structures of the female and male reproductive systems: RECAP: Reproductive systems

5. Fantastic Fact! In each ejaculation, up to 500 million sperm are released!

6. Babies are made by a mother and a father but how does this actually happen? During adolescence , your body becomes able to create a baby with someone of the opposite sex. Something to think about … How are babies made? Egg cells and sperm cells ( gametes ) need to join together to start the process of making a baby.  This is called fertilisation . 

7. What are gametes ? Gametes are reproductive cells . They join together to create a new organism. The male gamete is a sperm cell . The female gamete is an egg cell . To create a new organism, the nucleus of the sperm and the nucleus of the egg join together – this is known as fertilisation . This process takes place in most animals. Q – Describe what is meant by a gamete .

8. Where do sperm cells meet an egg cell ? Each ovary is connected to the uterus by an oviduct . An egg cell cannot move by itself. However, the oviduct is lined with cilia – these are tiny hairs on the surface of cells. Every month, an egg is released from an ovary. The cilia then waft the egg along the inside of the oviduct towards the uterus. The sperm are released into the vagina in semen during sexual intercourse . They then swim towards the egg in the oviduct. Q – Describe how an egg cell travels along the oviduct.

9. What happens during sexual intercourse ? When people ‘have sex’ or ‘make love’, semen is released into the vagina . People do this to make a baby or to show how much they care for each other. It is a very intimate act that gives many people a lot of pleasure. When a male becomes sexually aroused, his penis fills with blood and becomes erect. When a woman becomes sexually aroused her vagina becomes moist. This allows the penis to enter her vagina. During intercourse, the male moves his penis backwards and forwards. This increases the pleasure and stimulates the release of semen into the vagina. This is known as ejaculation . Q – Describe what happens during sexual intercourse.

10. How do sperm cells reach the egg cell ? 1. Sperm cells swim from the vagina t o the uterus . 2. They enter the uterus through the cervix and travel to the oviduct . 3. If a sperm cell meets an egg cell there, fertilisation can happen. 4. The fertilised egg divides several times to form a ball of cells called an embryo. 5. The embryo attaches to the lining of the uterus and begins to develop into a baby. This is called implantation . Q – Describe what happens during implantation.

11. Why do some couples have difficulty getting pregnant? There are a number of reasons why people may have difficulty having a baby. This is known as low fertility (or infertility ). Common male problems include a low sperm count (not producing many sperm) or producing sperm that do not swim properly. Common female problems include egg cells not being released monthly or blocked fallopian tubes. Q – Describe one cause of infertility in males and females.

12. EXTENSION: Literacy Task Journey to the egg! Describe the journey of a sperm cell from being made in the testes to the implantation of the fertilised egg in the lining of the uterus.

13. EXIT TICKET FERTILSATION EJACULATION IMPLANTATION CILIA GAMETES The fertilised egg attaches to the lining of the uterus. The nuclei of the sperm and egg cell join together. The little hairs that move the egg cell along the oviduct. Semen is released into the vagina. Reproductive cells.