The cell and the properties of life
Answers are for parents and teachers.
1
Match cell parts with functions: membrane, nucleus, lysosome, ribosome, mitochondrion.
Membrane – selective passage; nucleus – control; lysosome – breakdown; ribosome – protein; mitochondrion – energy.
2
Why is water important for a cell? Write 3 reasons.
Substances enter and leave with water; reactions happen in water; dissolved salts keep the internal environment constant.
3
List five properties of life and give one example of each.
For example: growth – a child gets taller; respiration – taking in oxygen; excretion – sweat and urine; reproduction – cell division; excitability – pupil narrowing in light.
4
Why should a person drink when very thirsty, and why is it good to drink water through the day even without thirst? Link with homeostasis.
Water is needed to keep the internal environment and blood steady; too little disturbs it, and the kidneys remove the excess.
5
List the organic substances in a cell and state the role of each.
Proteins – building and enzymes; fats and carbohydrates – energy; nucleic acids – hereditary information.