S4_Science_Keyword

Front

Balance Diet

Back

A balance diet is a diet that contains sufficient amounts of carbohydrates, dietary fibre, fats, proteins minerals, vitamin and water in order to live healthily

Front

Why it is important to complete the course of antibiotics?

Back

To ensure all the bacteria have been killed. Otherwise, the bacteria might mutate and develop a resistance to the antibiotics, which would result in a risk of relapse and an infection that might become more difficult to cure.

Front

Explain how the action of wearing face mask prevent others from becoming unwell.

Back

This prevents others from being infected by the microbes that are spread through the student's respiratory droplets.

Front

Explain how the action of using hand disinfectant prevent others from becoming unwell.

Back

This prevents the growth of microbes on surfaces that the unwell people touch, thereby preventing others from getting infected.

Front

Describe two environmental problems associated with Slash and Burn

Back

This leads to large-scale deforestation.

When forests are burned, huge amounts of smoke and harmful gases are released into the atmosphere, contributing to air pollution and global warming.

Front

Give three differences between exhaled and inhaled air.

Back

Exhaled air has a lower amount of oxygen than inhaled air.

Exhaled air has a higher amount of carbon dioxide than inhaled air.

Exhaled air has a higher amount of water vapour than inhaled air.

Front

A metal pan with a metal handle is heated over a flame. Explain why the handle of the metal pan gets hot.

Back

Thermal energy is transferred from a region of higher temperature to a region of lower temperature. Thus, thermal energy is transferred from the part where the metal pan is heated to the handle of the metal pan which is not heated.

Front

State two ways the mechanic can increase the moment on the nut.

Back

She can increase the force exerted on the spanner.

She can increase the distance between the point where the force is exerted on the spanner and the pivot.

Front

The gardener wants to plant flowers that grow best in soil that has a pH value of 6. Explain why the gardener should use universal indicator instead of litmus paper to measure the pH of the soil.

Back

Litmus paper is only used to determine if a solution is acidic or alkaline whereas a universal indicator can be used to measure pH.

Front

Explain why people are not allowed to smoke cigarettes in public places like restaurants and shops

Back

By not allowing people to smoke cigarettes in public places, other people will not be exposed to passive smoke which may cause respiratory diseases such as bronchitis and lung cancer.