Comparisons: Science

To download the accompanying lesson plan, please click on the link to the right of the screen.

Comparatives and superlatives

• Hypertension results in greater pressure exerted on the heart because the blood has to be pushed through a much smaller diameter.
• Objects with larger mass exert a greater gravitational pull than objects with smaller mass.
• The stable position is the one where the centre of gravity is at its lowest point.
• Which of the metals reacted fastest with dilute acid?

Most / least

most: Most flowers have both male and female reproductive structures.
least: Silver is the least reactive of all these metals.

Equality and inequality

as … as: Alcohol-based cleaners are not as harmful to humans as other cleaning fluids.
less … than: Large hydrocarbons are less flammable than smaller hydrocarbons.
more than: Brass expands more than iron when heated.
the more … the less …: The more pulleys there are in a system, the less effort is required.

Phrases for comparing and contrasting two items

compare: Compare the physical and chemical properties of sand, loam and clay.
differ: Plant cells differ in structure to animal cells.
difference: What is the difference between physical and chemical digestion?
similar to: The iris is similar in function to the diaphragm in the camera.
unlike: Unlike plants, animals cannot produce their own food.
vary: Processes for temperature regulation vary in different endothermic animals.

Verbs which describe greater or lesser degrees

exceed: A sound exceeding 100 dB can cause deafness in humans.
reduce: Resistance can be reduced by streamlining the shape of the object.

Compound words to form adjectives for describing shape and structure

-like: jelly-like, leaf-like, funnel-like, finger-like, wave-like, bone-like, thread-like, cup-like, tape-like, glass-like
-shaped: U-shaped, bowl-shaped

Prefixes

over- : overcrowded; overfishing; overgrazing; overgrowth; overheat; overloading; overpopulation; over-secretion; overweight
under- : underactive; under-secretion; underweight   

Discourse markers

on the other hand: Transparent materials are capable of transmitting light so that objects or images can be seen clearly. Translucent materials, on the other hand, only allow some light to pass through them and cannot be seen through clearly.
while: Oxygen is a waste product in photosynthesis, while carbon dioxide is a waste product of respiration.
however: Microwaves, radio waves and X-rays are all types electromagnetic radiation, however, light is the only radiation that can be seen with the naked eye.