O Level Science Notes Archives - Page 13 of 33 - Free ZIMSEC & Cambridge Revision Notes

Metal and metal alloy properties and their construction uses

By garikaib|2025-02-12T09:21:53+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Metals are popular in construction. Image credit traveldigg.com ZIMSEC O Level Combined Science Notes: Metal and metal alloy properties and their construction uses

Metals are popular construction materials
They have properties that make them suited for making diverse structures
They are ductile which means […]

Comments Off

Machines: The inclined plane
Gallery
Machines: The inclined plane

Notes, O Level Science Notes, Ordinary Level Notes

Machines: The inclined plane

By garikaib|2025-02-12T09:39:15+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

ZIMSEC O Level Combined Science Notes: Machines: The inclined plane

Is also known as a ramp
is a flat supporting surface tilted at an angle,
with one end higher than the other,
used as an aid for raising or lowering a load
Inclined planes are widely used to move heavy loads over vertical obstacles
examples vary from a […]

Comments Off

Hydraulic brakes

By garikaib|2025-02-12T09:10:35+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Car brakes. Image driverside.com ZIMSEC O Level Combined Science Notes: Hydraulic brakes

Is another example of hydraulic machines
Pressure is applied on the brake pedal using the car driver’s foot

Car brakes. Image credit dtzone.com […]

Comments Off

Immunity and Immunisation

By garikaib|2025-02-12T09:28:55+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Sindiso Marume holding her brother’s health card. Image credit irinnews.org ZIMSEC O Level Combined Science Notes: Disease:Immunity and Immunisation

Immunity-is the ability of the body to resist diseases
There are various types of immunity:

Antigen-is any substance that causes […]

Comments Off

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 […]

Comments Off

Plant pests and diseases

By garikaib|2025-02-12T09:04:25+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A grasshopper. Image credit nutrainigridients.com A grasshopper. Image credit nutrainigridients.com ZIMSEC O Level Combined Science Notes: Plant pests and diseases

In the wild there is a balance in nature.
The are few pests and diseases that destroy plants.
In crop plants there are more pests that cause and spread disease.
This is because there […]

Comments Off

Inhaled vs Exhaled air experiment: Method 1

By garikaib|2025-02-12T09:37:32+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Image credit vimeo.com ZIMSEC O Level Combined Science Notes: Inhaled vs Exhaled air experiment: Method 1

Aim: Comparing the inhaled and exhaled air.

Materials: large transparent container (e.g. bell jar), candle, tin lid, water, large basin, rubber tubing, ruler.

Method

exhaled_inhaled_air-min

Place the large […]

Comments Off

Health and well being

By garikaib|2025-02-12T09:10:54+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Exercise is key to maintaining one’es health. Image credit centrictv.com ZIMSEC O Level Combined Science Notes: Health and well being

Health is the absence of disease
It is a state of being physically and psychologically well.
A person is said to be healthy […]

Comments Off

Asexual reproduction

By garikaib|2025-02-12T09:34:33+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

A bud on a sugarcane cutting. Image credit 10degreesabove.com ZIMSEC O Level Combined Science Notes: Reproduction in plants: Asexual reproduction/ Vegetative reproduction

Is also known as asexual reproduction
This takes place when plants reproduce without producing seeds
Such plants have modified stems, roots or […]

Comments Off

Variation

By garikaib|2025-02-12T08:59:05+02:00February 12th, 2025|Notes, O Level Science Notes, Ordinary Level Notes|

Variation in chillies. Image credit chilipapryczka.pl ZIMSEC O Level Combined Science Notes: Variation

The living world has many thousands of different types of plants and animals
For example lions are different from hyenas which in turn are different from say goats
In plants the Msasa trees are […]

Comments Off

February 2025