Challenge: Identify the type of graph you would draw for continuous and discontinuous - PowerPoint Presentation

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Challenge:

Identify the type of graph you would draw for continuous and discontinuous variation

Explain how a sperm cell is adapted to its function

Describe continuous variation, and give an example

Describe what the reactivity series is

Describe the role of bone marrow in the body

LAST LESSON

LAST WEEK

LAST TOPIC

LAST YEAR

Menstrual Cycle

Explain the events of the menstrual cycle and how the menstrual cycle links with pregnancy

Fertilisation, Menstruation, Cycle, Hormone, Oestrogen, Progesterone, FSH, LHDefine fertilisation

Identify key events on a diagram of the menstrual cycleExplain why pregnancy is more or less likely at certain stages of the menstrual cycle

List

all the changes that occur in males and females during puberty.

Female

Male

Fertilisation

What is fertilization?

Consider what the image above is showing you

Why is it important?

Fertilisation

is when a sperm cell joins with an egg cell. It is important because this is how reproduction occurs in most living things including humans

T

he menstrual cycle

What changes?

Why does it change?

What causes it to change?

The menstrual cycle is the body’s way of

preparing for pregnancy.

It only happens in females.

It is controlled by chemicals called hormones.

Several 

hormones

 are involved in the menstrual

cycle of a woman:follicle stimulating hormone (FSH)

 causes the maturation of an egg in the ovary.luteinising hormone (LH) stimulates the release of the egg.

oestrogen is involved in repairing and thickening the uterus lining

Progesterone

maintains the uterus lining

FSH

is secreted by the pituitary gland. It makes eggs mature and stimulates the ovary to produce oestrogen.

Uterus lining

breaks down -

menstruation

Lining of uterus builds up

Lining

maintained

The level of

oestrogen

rises. This inhibits

the production of more FSH and stimulates the build up of the lining of the

uterus -

proliferation

LH

is secreted by the pituitary gland. When its level reaches a peak it stimulates the release of a mature egg from the

ovary

-

ovulation

After the egg is released the level of

progesterone

rise and maintains the lining of the uterus in preparation for the implantation of the fertilised egg.

The Menstrual Cycle

28

27

26

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24

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20

19

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15

14

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10

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3

2

1

The main events in the cycle are

:

1

) Menstruation –

uterus lining breaks down,

blood and cells are lost.

2

) Proliferation –

repair of the uterus

lining.

3

) Ovulation –

release

of an egg from the

ovary – day 14

4 hormones involved:

FSH

Oestrogen

LH

Progesterone

Cycle starts again

Label

the key events on this menstrual cycle timeline

State where in the menstrual cycle pregnancy is most likely to occur.

Justify your answer

Challenge

: Apply knowledge of the menstrual cycle to graphs showing the hormones involved.

Todays Lesson

Last Lesson

Last

Last Lesson

Describe the process of menstruation

Recall the key components of the female reproductive system

Explain

the importance of adaptations

Menstruation (days 1-6)

Changes in the uterus

Changes in the ovary

Follicles immature

Pituitary gland releases FSHUterus lining breaks

Changes in hormone levels:

Proliferation (days 6-13):

Eggs begin to develop

Uterus lining repairs

FSH causes: New egg to developOestrogen releaseOestrogen:Stops FSH (prevents more eggs developing) Starts LH release

Uterus lining thickensChanges in the ovary

Changes in the uterus

follicle releases egg

Uterus lining remains thick

Changes in the ovary

Changes in the uterus

High LH level:Causes follicle to bust & release egg into oviduct

Ovulation (day 14):

After day 14

If the egg gets fertilised by a sperm

(pregnancy occurs):

Oestrogen and progesterone remain at high levels. These hormones maintain the uterus lining,

so menstruation does not occur. If the egg is not fertilised:

Follicle forms a yellow body & the egg dies. Hormone production stops.

Low progesterone

causes uterus lining to break, the next menstruation starts and the cycle continues.