Year 7B Reproduction © Tony P. Thould September 2000

National Curriculum Statements linked to this Unit 1bThe functions of chloroplasts and cell walls in plant cells and the functions of cell membrane, cytoplasm and nucleus in both plant and animal cells 1c ways in which some cells including ciliated epithelial cells, sperm, ova and root hair cells are adapted to their functions. 1d that fertilisation in humans and flowering plants is the fusion of the male and female cell 1eTo relate cells and cell functions to life processes in a variety of organisms.

2f About the physical and emotional changes that take place during adolescence. 2g about the male and female reproductive organs including the menstrual cycle. 2h how the fetus develops in the uterus including the function of the placenta. 2m that the abuse of alcohol, solvents and other drugs affect health. The National Curriculum Programme of Study Statements

REPRODUCTON In order for a plant or animal species to survive they must reproduce. Most plants and animals reproduce by sexual reproduction which involves a male sex cell joining with a female sex cell. This is called fertilisation.

REPRODUCTON In order for a plant or animal species to ………………. they must reproduce. Most plants and animals reproduce by …………….. ………………….which involves a male sex cell joining with a female sex cell. This is called……………...

1.Why do some animals/ plants produce only a few young whilst others produce hundreds or thousands? 2.What is an endangered species? 3.What is the difference between Internal and External Fertilisation? 4.In what ways can Man help Plants / Animals to survive? Minimum you must answer is Questions 1,2 and 3.

AN OVUM CELL Contains the female set of chromosomes. Allows only one sperm inside before blocking any other ones from getting in Nucleus Cell Membrane

A SPERM CELL Tail for swimming Nucleus with male chromosomes Acrosome to make a hole in the ovum wall for the sperm to get into the ovum Mitochondrion to make energy to move the tail Its job is to fertilize the ovum ( egg ) cell Test

Fertilisation The Sperm cell uses its tail to swim to the Ovum The Acrosome dissolves a hole in the Ovum wall and one Sperm enters

FERTILIZATION Pollen + Ovule = Seed Carries the Male Chromoso mes in its Nucleus Contains the Female Chromoso mes in its Nucleus These are each a HALF SET of Chromosomes so that when they join together they form a WHOLE SET in the seed. A Fully Fertilized Ovule

FERTILIZATION Sperm + Ovum = Foetus Carries the Male Chromoso mes in its Nucleus Contains the Female Chromoso mes in its Nucleus These are each a HALF SET of Chromosomes so that when they join together they form a WHOLE SET in the seed. A baby with a full set of Chromosom es

FERTILIZATION There are two types of fertilisation :- EXTERNAL This takes place outside the female body e.g. Frogs, where the female lays her eggs in water and the male sheds his sperm over them INTERNAL This takes place inside the female body e.g. Man, where the sperm are placed inside the females body and they swim to the Ovum.

The female lays her eggs in a shallow hollow in the sea bed Male releases his sperm into the water nearby EXTERNAL FERTILISATION Fertilisation takes place outside the females body

GERMINATION Once the seeds have been dispersed they need the right conditions to start growing into a new plant - Germination. These conditions are:- Warmth Moist Air Light/Dark

THESE ORGANS HELP WITH REPRODUCTION The male sex organs are made up from the Penis, Testes and Scrotum. The Testes make Sperm which contain the male genes. The Penis places the sperm as near as it can to the female’s egg ( Ovum ) The female sex organs are made up from the Ovaries, Vagina, Uterus and Oviduct. The ovaries make the Ovum which contains the female genes. The Uterus ( womb ) holds the developing baby.

THE MALE SEX ORGANS Bladder Seminal Glands Sperm Duct Testicle Penis Erectile Tissue Pubic Bone

THE FEMALE SEX ORGANS Ovary Uterus or Womb Cervix Vagina Ovum released from the ovary into the Oviduct Oviduct

THE MALE SEX ORGANS

THE FEMALE SEX ORGANS

In a flowchart draw and label the path taken by a Sperm Cell from leaving the Testicle to fertilising the Ovum Cell

THE MAIN PARTS OF A FLOWER Sepal Stamen Petal Carpel Filament Anther Stigma Style Ovary Test Ovule

THE MAIN PARTS OF A FLOWER

THE FUNCTIONS OF THE MALE PARTS Stamen Anther Filament Makes pollen which has the male genes in it Holds the Anther up in the air so that visiting insects brush against it Different plants have different numbers, shape and sizes of Stamens Test

THE FUNCTIONS OF THE FEMALE PARTS Stigma Style Ovary Carpel A sticky surface where pollen stays when visiting insects brush against it. Guides the pollen tube down to the Ovary. Makes the Ovules which contain the female genes. Forms the fruit. Ovule Test

THE FUNCTIONS OF THE MALE PARTS Stamen Different plants have different numbers, shape and sizes of Stamens

THE FUNCTIONS OF THE FEMALE PARTS Stigma Style Ovary Carpel Ovule

THE MENSTRUAL CYCLE Every month once puberty has been reached, an egg or Ovum is released from one of the ovaries in the female. This is called Ovulation. If the Ovum is not fertilised then it leaves the body through the Vagina along with the lining of the Uterus which had become thicker and richly supplied with blood. This happens every month and is known as a Period or Menstrual Cycle.

Day 7 Day 14Day 21 Day 28 THE MENSTRUAL CYCLE

Week One An Ovum is made in the Ovary ready to be released into the funnel of the Oviduct. Oviduct Ovary Uterus Vagina

THE MENSTRUAL CYCLE Week Two The Ovary releases the Ovum into the funnel of the Oviduct. This is Ovulation. The Uterus wall thickens ready for the fertilised Ovum

Week Three The Ovary travels down the Oviduct towards the Uterus. THE MENSTRUAL CYCLE The wall of the Uterus is well supplied with blood.

THE MENSTRUAL CYCLE Week Four As the Ovum was not fertilised, the Uterus wall is shed with the Ovum - the Period.

THE MENSTRUAL CYCLE Day 7 Day 14 Day 21Day 28 What is happening during each week of the month of the Menstrual Cycle?

THE MENSTUAL CYCLE Once the period has finished the whole cycle begins again and continues each month as long as the Ovum is not fertilised. To prevent the fertilisation of the Ovum many couples take precautions which stops the Sperm reaching the Ovum - Contraception

EARLY PREGNANCY The Embryo ( baby ) is held in the wall of the Uterus and is joined to the Placenta by the Umbilical Cord. The baby gets food and oxygen from the mothers blood through the Placenta. It also gets rid of waste into the mothers blood through the Placenta

THE PLACENTA Placenta The Placenta forms a barrier between the blood of the mother and the baby but allows substances to pass between them.

THE PLACENTA Placenta Oxygen, sugar, protein, vitamins, minerals, water, antibodies all pass from the mothers’ blood, along the Umbilical Vein in the umbilical cord to the baby.

THE PLACENTA Placenta Waste products such as Carbon Dioxide, Urea and excess salts pass from the baby along the Umbilical Artery in the unbiblical cord to the Placenta and into the mothers blood so that her body can get rid of it.

THE PLACENTA Food and Oxygen in the mothers blood Waste food and Carbon Dioxide The Umbilical Cord carries food and Oxygen to the baby and waste away. Placenta

THE PLACENTA Placenta Unfortunately, some harmful substances can pass from the mothers blood into the baby e.g. Alcohol, Drugs, Nicotine and AIDS

THE AMNION Placenta This is a bag that surrounds the baby and is filled with a fluid which protects the baby from bumps and bangs. The Amnion

NINE MONTHS LATER The baby is ready to be born. The head is engaged - in the right position for birth, at the mouth of the Uterus, the Cervix. Cervix Placenta or Afterbirth

Adolescence When children reach their teens many physical and emotional changes take place which some of them find difficult to come to terms with.

PRIMARY SEXUAL CHARACTERISTICS MalesFemales Secondary Sexual Characteristics These are changes in the bodies of boys and girls when they are changing from a boy to man and girl to woman

Physical Changes Puberty is the period when certain physical changes take place in the male and female body usually in early teens. Males Pubic facial and armpit hair grows Voice breaks and deepens More muscular body Sperm produced by testes. Females Pubic and armpit hair grows Breasts develop and body more curved Menstrual cycle begins giving her monthly periods

Physical Changes Puberty is the period when certain physical changes take place in the male and female body usually in early teens. Males Females

Emotional Changes Puberty is the period when certain emotional changes take place in the male and female body usually in early teens. Serious thoughts about the opposite sex leading to relationship problems with each other, or peers ( pressured to have sex ) or parents ( you are not going out ), or even with oneself - internal conflict ( should I or shouldn’t I ). More conflict with adults as opinions are stronger and arguments take place. Behavioural problems due to wider exposure to influences and peer group pressure.