sexual reproduction Archives - Page 2 of 2 - Free ZIMSEC & Cambridge Revision Notes

Contraception: Male or Female condoms

By garikaib|2025-02-12T09:40:51+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

couple_smiling-min

ZIMSEC O Level Combined Science Notes:Contraception: Male or Female condoms

Are one of the most commonly used contraceptives

How it works Images credit netdoctor.co.uk

The male condom is used to sheath(cover) an erect penis just before sex
The female condom is […]

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Contraception: Diaphragm/Dutch cup

By garikaib|2025-02-12T09:41:47+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A married couple. Image credit rawstory.com ZIMSEC O Level Combined Science Notes:Contraception:Diaphragm/Dutch cup

Is also known as a cervical cap

How it works A diaphragm/cervical cap. Image credit path.org

Rubber cap/dome placed […]

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Contraception: The use of spermicides

By garikaib|2025-02-12T09:43:53+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Couple having dinner. Image credit singleblackmale.org ZIMSEC O Level Combined Science Notes:Contraception:Ways to prevent pregnancy

Spermicides are sperm killing chemicals

How it works

Are usually in the form of jelly cream placed into the vagina before sexual intercourse
The chemical kills spermatozoa

Effectiveness

60-95%

Advantages

Does not require […]

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Contraception: Loop/IUD (intrauterine device)

By garikaib|2025-02-12T09:44:32+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Black couple. Image credit classic105.com ZIMSEC O Level Combined Science Notes:Contraception:Ways to prevent pregnancy

How it works IUD IUD

Is a small copper/plastic device placed inside the uterus
It prevents the embryo from implanting in the uterus
by […]

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Contraception: Sterilisation

By garikaib|2025-02-12T09:45:27+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Black couple. Image credit blackcouplegetaways.com ZIMSEC O Level Combined Science Notes:Contraception:Ways to prevent pregnancy

How it works

Can be done in both men and women
In men it is known as a vasectomy
- Sperm duct is cut and tied
- During sexual intercourse ejaculated fluid contains no sperm

[…]

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Contraception: Abstinence

By garikaib|2025-02-12T09:46:09+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Couple holding hands. Image credit neguswhoread.com ZIMSEC O Level Combined Science Notes:Contraception: Abstinence

It involves total avoidance of sexual intercourse

Adavantages

Many couples agree to wait until marriage
There is no risk of contracting Sexually Transmitted Infections
It is 100% effective
It is supported by most religious […]

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Causes of infertility

By garikaib|2025-02-12T08:57:00+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Sterility can cause strain in a relationship. Image credit colossiansfamilynetwork.org ZIMSEC O Level Combined Science Notes: Causes of infertility

Sterility is the inability to reproduce
There are a number of causes for sterility
Low sperm count (makes it […]

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Reproduction in Humans

By garikaib|2025-02-12T09:31:34+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A Zimbabwean family ZIMSEC O Level Combined Science Notes: Reproduction in Humans

Human being produce sexually
The process involves the fusion (joining) of the nuclei (sex cells) of the male gamete (sperm)
and the female gamete (ovum)
To form a zygote
The human and female sexual organs take […]