UNIT 4

INDEX

 

1. REPRODUCTION

1.1         REPRODUCTION

§  Reproductive cells

1.2         SEXUAL FEATURES

§  Primary sexual features

§  Secundary sexual features

 

1.1 REPRODUCTION

Reproduction is a life process that lets living things create others living things that are similar to them. Human beings reproduce through sexual reproduction because their reproduction unites male and female sex cells. Humans are viviparous mammals.

Reproductive cells are responsible for carrying out the function of reproduction. There are two types:

§  Ovules: They are the female reproductive cells. They are big and round. They are immobile.

§  Sperm: They are the male reproductive cells. They are small. They have a head and a long tall called a flagellum that helps them move.

1.2 SEXUAL FEATURES

Primary sexual features are the traits that characterise the male and female reproductive systems. Reproductive systems are already formed at birth and tell us if the newborn is a boy or a girl.

Secondary sexual feature develop during puberty. There are some physical changes that are the same for both sexes, like hair growing in the armpit and pubic areas. Other changes specific to each sex are:

§  Girls develop breasts and their hips get wider.

 

ACTIVITIES

1.  Write a sentence with each group of words.

·      Reproduction/ sex cells/ union/ovule and sperm

·      Primary sexual features/reproductive systems

·      Secondary sexual features/ puberty

2.  What is reproduction?

 

3.  Draw the reproductive cells and write their names.

 

4.  Copy and complete the sentences.

·       Human beings reproduce through ________________because their reproduction ________ male and female sex cells. Humans are ________________.

·      Reproductive cells are responsible for _____________ the function of reproduction.

·      Ovules are _____________ reproductive cells. They are __________.

·      Sperm are _____________ reproductive cells. They are_______. They have a _______ and a ___________ called a __________that helps them ________.

 

5.  Write True or False and correct the sentences.

·      Primary sexual features are the traits that characterise the male and female nervous systems.

·      Girls develop breasts and their hips get wider.

·      Reproductive systems are already formed at puberty and tell us if the newborn is an animal or a human.

·      Secondary sexual feature develop during puberty.

   Boys get deeper voices, they get facial hair and their shoulders get wider.