Characteristics of living organisms

1. Which list contains only characteristics of living organisms used in this topic?

1. Movement, respiration, sensitivity, growth, reproduction, excretion and nutrition
2. Movement, breathing, hearing, growth, feeding, circulation and excretion
3. Locomotion, combustion, sensitivity, repair, reproduction, digestion and nutrition
4. Movement, respiration, sight, growth, reproduction, egestion and feeding

2. A closed flower opens its petals at sunrise without changing its location. Which characteristic is directly shown by the petals changing position?

1. Growth
2. Nutrition
3. Movement
4. Excretion

3. A woodlouse travels from a dry area into a damp shelter. Which observation is the clearest evidence of movement?

1. It remains the same mass.
2. Its whole body changes place.
3. The shelter contains water vapour.
4. Its offspring resemble it.

4. Which statement correctly describes respiration?

1. Air moves into and out of the lungs and releases energy there.
2. Food moves through the digestive system and becomes energy immediately.
3. Carbon dioxide enters cells so that nutrient molecules can be stored.
4. Chemical reactions in cells break down nutrient molecules and release energy.

5. Why is breathing not the same process as respiration?

1. Breathing moves air, whereas respiration is a set of chemical reactions in cells.
2. Breathing occurs only in plants, whereas respiration occurs only in animals.
3. Breathing makes nutrient molecules, whereas respiration moves them into the lungs.
4. Breathing removes undigested food, whereas respiration removes urine.

6. Living germinating seeds warm an insulated flask, while boiled seeds in an identical flask do not. Which conclusion is best supported?

1. Boiled seeds grow faster because their temperature stays constant.
2. The living seeds are breathing through lungs inside the flask.
3. Respiration in the living seeds releases energy, and some is transferred as heat.
4. The temperature rise proves that the seeds are reproducing.

7. Which observation most directly shows sensitivity?

1. A seed has a mass of 4.0 g before soaking.
2. A pupil narrows immediately after light intensity increases.
3. A bird's feather is 6 cm long.
4. A leaf contains stored nutrient molecules.

8. Which sequence gives evidence of sensitivity to an internal change?

1. A stone becomes warm in sunlight and cools after sunset.
2. A dry sponge takes up water and becomes heavier.
3. A metal rod expands as its temperature rises.
4. Body water availability falls, the change is detected, and thirst leads to drinking.

9. Which measurement gives the strongest evidence that a group of seedlings has grown?

1. Their total dry mass increased and remained higher.
2. Their fresh mass rose immediately after watering.
3. Their leaves folded during the night.
4. Their pots became warmer in sunlight.

10. Matched equal-sized groups of seedlings are grown identically. Their average dry masses are 2.4 g per seedling for the group sampled on day 4 and 3.0 g per seedling for the group sampled on day 10. What change occurred relative to the day-4 value?

1. An increase of 0.6 g, which is 20%
2. An increase of 5.4 g, which is 25%
3. An increase of 0.6 g, which is 25%
4. A decrease of 0.6 g, which is 20%

11. A dry bean absorbs water and swells, then returns to its original mass after drying. Why is the swelling alone not secure evidence of growth?

1. Growth can occur only when an organism changes location.
2. The change is reversible and can be explained by water uptake.
3. Living organisms never take in water during growth.
4. Growth is defined as producing offspring of the same kind.

12. Which event is reproduction rather than growth or repair?

1. A cut in an animal's skin closes as tissue is repaired.
2. A tree trunk becomes wider over several years.
3. A lizard replaces damaged skin at a wound.
4. A runner from a parent plant forms a separate new plant.

13. Why is reproduction considered a characteristic of living organisms even though one individual may never reproduce?

1. Reproduction allows the species to continue across generations.
2. Reproduction releases all energy needed by that individual.
3. Reproduction removes every metabolic waste from that individual.
4. Reproduction is the only way an individual can respond to stimuli.

14. A strawberry runner develops roots and leaves, then becomes separated from the parent. What observation identifies reproduction most clearly?

1. The runner contains more water after rain.
2. One leaf changes its angle during the day.
3. A separate new strawberry plant has formed.
4. The parent plant releases carbon dioxide.

15. Which is an example of excretion?

1. Passing undigested fibre out of the digestive system
2. Removing carbon dioxide produced by respiration
3. Releasing saliva to help process food
4. Taking nutrient molecules into the body

16. Why is removal of undigested food classified as egestion rather than excretion?

1. The material contains too much carbon dioxide for respiration.
2. The material is always useful to every cell in the organism.
3. The material was produced only during reproduction.
4. The material was not absorbed and was not made as a metabolic waste by cells.

17. Which removal counts as excretion because the substance is present beyond requirements?

1. Removing excess water in urine
2. Removing an uneaten seed from a food dish
3. Removing loose soil from an animal's fur
4. Removing an unchewed leaf from the mouth

18. Which statement best describes nutrition?

1. Moving air so that energy is released in the lungs
2. Detecting every change without producing a response
3. Taking in materials needed for energy, growth and development
4. Removing only food that could not be digested

19. Which comparison between nutrition and respiration is correct?

1. Nutrition removes metabolic waste; respiration produces new organisms.
2. Nutrition supplies nutrient materials; respiration breaks down nutrient molecules in cells to release energy.
3. Nutrition is movement toward food; respiration is movement away from danger.
4. Nutrition occurs only in plants; respiration occurs only in animals.

20. An organism moves toward shade after the surroundings become hotter. Which pairing is best supported?

1. Growth and reproduction
2. Excretion and nutrition
3. Respiration and egestion
4. Movement and sensitivity

21. Which set of observations gives the strongest evidence that an unfamiliar object is a living organism?

1. It takes in materials, responds directionally to change, gains dry mass and produces similar offspring.
2. It rolls downhill, becomes warm in sunlight and stops at a wall.
3. It becomes larger when inflated and smaller when air is released.
4. It gives off gas during one chemical reaction and then disappears.

22. A flame spreads, consumes fuel and releases carbon dioxide. Why do these facts alone not prove that it is living?

1. Every living organism must walk from one place to another.
2. Only organisms that make flowers can reproduce.
3. Similar-looking changes can result from combustion rather than coordinated life processes.
4. Living organisms never release carbon dioxide.

23. A dormant seed shows no visible movement during a short observation. Which conclusion is most scientifically sound?

1. The seed cannot be living because every life process must be obvious at all times.
2. Absence of visible movement in a short period does not show that the seed is non-living.
3. The seed is living only if it changes location before the observation ends.
4. The seed must be reproducing because it remains still.

24. Which evidence-and-characteristic match is incorrect?

1. A shoot tip changes position — movement
2. A new organism forms — reproduction
3. Dry mass increases permanently — growth
4. Undigested fibre leaves the body — excretion