حل أوراق عمل Cycling of Matter العلوم المتكاملة الصف السابع انسبير
حل أوراق عمل Cycling of Matter العلوم المتكاملة الصف السابع انسبير
Lesson 3: Cycling of Matter
1. ?What is the role of phytoplankton in the carbon cycle
a) They release carbon dioxide into the atmosphere.
b) They convert carbon dioxide into calcium carbonate for their skeletons.
c) They decompose dead organisms to release carbon dioxide.
d) They use carbon dioxide to produce methane.
2.? What happens to the carbon in phytoplankton when they die
a) It evaporates into the air.
b) It is immediately used by other organisms.
c) It sinks to the ocean floor and becomes fossilized.
d) It is released as methane gas.
3. How does carbon dioxide re-enter the atmosphere from chalk of phytoplankton fossilized skeletons
a) Through the process of photosynthesis.
b) Through the process of weathering by rain and waves.
c) Through the consumption of fossil fuels.
d) Through volcanic eruptions.
4. ?How do humans and other animals obtain carbon
a) From the air they breathe.
b) From the water they drink.
c) From the food they eat.
d) From photosynthesis.
5. What process returns carbon to the soil and releases carbon dioxide into the atmosphere when organisms die
a) Photosynthesis
b) Decomposition
c) Combustion
d) Respiration
6. Use the above diagram to complete the following table
| Takes in CO2 from the atmosphere | Releases CO2 into the atmosphere |
| Photosynthesis | Combustion |
| Cellular respiration | |
| Decomposition |
7. Which of the following processes contributes to water vapor entering the atmosphere from plants
a) Evaporation
b) Condensation
c) Precipitation
d) Transpiration
8. ?What happens to water after it falls to Earth’s surface as precipitation
a) It only enters bodies of water
b) It only soaks into the soil
c) It either enters bodies of water or soaks into the soil
d) It remains in the atmosphere
9. ?Which process in the water cycle involves water vapor cooling and forming clouds
a) Evaporation
b) Precipitation
c) Condensation
d) Transpiration
10.? Which stage of the water cycle can involve snow or hail
a) Evaporation
b) Transpiration
c) Precipitation
d) Condensation
11. What is the process called that changes atmospheric nitrogen into a form usable by living organisms
a) Photosynthesis
b) Nitrogen fixation
c) Evaporation
d) Condensation
12.? Which organisms primarily perform nitrogen fixation
a) Plants
b) Animals
c) Nitrogen-fixing bacteria
d) Fungi
13. ?In what form is nitrogen most abundant in the atmosphere
. a) Ammonia (NH3)
b) Nitrate (NO3)
c) Nitrite (NO2)
d) Nitrogen gas (N2)
14.? How do animals obtain the nitrogen they need
a) By breathing in nitrogen gas
b) By eating plants or other organisms
c) By drinking water
d) By absorbing nitrogen through their skin
15.? What role do decomposers play in the nitrogen cycle
a) They convert nitrogen gas into ammonia
b) They fix nitrogen from the atmosphere
c) They break down dead organisms and return nitrogen to the soil
d) They absorb nitrogen from the soil and release it as nitrogen gas
16. ?What is manure, and how does it contribute to the nitrogen cycle
a) Decomposed plant matter; provides carbon to plants
b) Animal waste; provides nitrogen to plants
c) Mineral fertilizer; provides phosphorus to plants
d) A type of soil; provides water to plants
17. Which component of proteins is essential for all organisms and is cycled through the environment
a) Oxygen
b) Hydrogen
c) Carbon
d) Nitrogen
18. Which process returns nitrogen to the environment from the waste products of organisms
a) Photosynthesis
b) Respiration
c) Decomposition
d) Transpiration
19. Draw arrows to complete the nitrogen cycle
20. ?What is the primary source of oxygen in Earth’s atmosphere
a) Cellular respiration
b) Photosynthesis
c) Combustion of fossil fuels
d) Volcanic activity
21. Which organisms are estimated to release more than 50 percent of the oxygen in Earth’s atmosphere
a) Trees
b) Marine animals
c) Phytoplankton
d) Fungi
22.What process is responsible for the initial introduction of oxygen into Earth’s early atmosphere
a) Volcanic eruptions
b) Evolution of photosynthetic bacteria
c) Meteorite impacts
d) Formation of the ozone layer
