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All questions of Ecosystems for Class 8 Exam
Which of the following is an example of a primary consumer?- a)Grass.
- b)Rabbit.
- c)Wolf.
- d)Mushroom.
Correct answer is option 'B'. Can you explain this answer?
a)
Grass.
b)
Rabbit.
c)
Wolf.
d)
Mushroom.
 | Eduskill Classes answered |
A primary consumer is an organism that eats producers (plants). Rabbits eat grass, making them primary consumers.
Which of the following best describes a food chain?- a)A group of organisms living in the same habitat.
- b)A linear sequence of organisms through which nutrients and energy pass.
- c)A complex network of interconnected food webs.
- d)The physical location where an organism lives.
Correct answer is option 'B'. Can you explain this answer?
a)
A group of organisms living in the same habitat.
b)
A linear sequence of organisms through which nutrients and energy pass.
c)
A complex network of interconnected food webs.
d)
The physical location where an organism lives.
 | Tutorpedia Coaching answered |
A food chain is a linear sequence of organisms through which nutrients and energy pass as one organism eats another.
Which of the following substances is most likely to bioaccumulate in a food chain?- a)Water.
- b)Carbon dioxide.
- c)Mercury.
- d)Oxygen.
Correct answer is option 'C'. Can you explain this answer?
a)
Water.
b)
Carbon dioxide.
c)
Mercury.
d)
Oxygen.
| | Eduskill Classes answered |
Mercury is a heavy metal that is not easily broken down or excreted, making it likely to bioaccumulate in a food chain.
Why are top predators often most affected by bioaccumulation?- a)They are exposed to more sunlight.
- b)They have longer lifespans.
- c)They are at the end of the food chain and accumulate toxins from all the lower levels.
- d)They eat a variety of different organisms.
Correct answer is option 'C'. Can you explain this answer?
a)
They are exposed to more sunlight.
b)
They have longer lifespans.
c)
They are at the end of the food chain and accumulate toxins from all the lower levels.
d)
They eat a variety of different organisms.
| | Tutorpedia Coaching answered |
Top predators are most affected by bioaccumulation because they are at the end of the food chain and accumulate toxins from all the lower levels, leading to higher concentrations of toxins in their bodies.
Which of the following is a common effect of biomagnification in aquatic ecosystems?- a)Increased biodiversity.
- b)Decreased sunlight penetration.
- c)Higher toxin concentrations in top predators.
- d)Faster water currents.
Correct answer is option 'C'. Can you explain this answer?
a)
Increased biodiversity.
b)
Decreased sunlight penetration.
c)
Higher toxin concentrations in top predators.
d)
Faster water currents.
 | Rahul Kumar answered |
Biomagnification often results in higher concentrations of toxins in top predators in aquatic ecosystems, affecting their health and survival.
How can bioaccumulation affect human health?- a)By increasing oxygen levels in the blood.
- b)By causing a buildup of essential nutrients.
- c)By leading to the accumulation of harmful toxins in the body.
- d)By promoting healthy growth and development.
Correct answer is option 'C'. Can you explain this answer?
a)
By increasing oxygen levels in the blood.
b)
By causing a buildup of essential nutrients.
c)
By leading to the accumulation of harmful toxins in the body.
d)
By promoting healthy growth and development.
| | Rahul Kumar answered |
Bioaccumulation can lead to the accumulation of harmful toxins in the human body, which can cause various health issues such as neurological damage and cancer.
In a food chain, what role do producers play?- a)They decompose dead organisms.
- b)They produce energy from sunlight.
- c)They consume primary consumers.
- d)They are top predators.
Correct answer is option 'B'. Can you explain this answer?
a)
They decompose dead organisms.
b)
They produce energy from sunlight.
c)
They consume primary consumers.
d)
They are top predators.
| | Eduskill Classes answered |
Producers, such as plants, produce energy from sunlight through photosynthesis, forming the base of the food chain.
What is bioaccumulation?- a)The process by which organisms break down substances.
- b)The process by which organisms eliminate toxins.
- c)The process by which organisms absorb and store toxins faster than they can eliminate them.
- d)The process by which organisms produce energy from food.
Correct answer is option 'C'. Can you explain this answer?
a)
The process by which organisms break down substances.
b)
The process by which organisms eliminate toxins.
c)
The process by which organisms absorb and store toxins faster than they can eliminate them.
d)
The process by which organisms produce energy from food.
| | Rahul Kumar answered |
Bioaccumulation refers to the process by which organisms absorb and store toxins from their environment at a rate faster than they can eliminate them.
What is the main difference between bioaccumulation and biomagnification?- a)Bioaccumulation occurs within an individual, while biomagnification occurs across trophic levels.
- b)Bioaccumulation occurs in plants, while biomagnification occurs in animals.
- c)Bioaccumulation happens in water, while biomagnification happens on land.
- d)Bioaccumulation reduces toxin levels, while biomagnification increases them.
Correct answer is option 'A'. Can you explain this answer?
a)
Bioaccumulation occurs within an individual, while biomagnification occurs across trophic levels.
b)
Bioaccumulation occurs in plants, while biomagnification occurs in animals.
c)
Bioaccumulation happens in water, while biomagnification happens on land.
d)
Bioaccumulation reduces toxin levels, while biomagnification increases them.
| | Eduskill Classes answered |
The main difference is that bioaccumulation occurs within an individual organism, while biomagnification refers to the increase in toxin concentrations as you move up through trophic levels in a food chain.
What is the primary source of toxins that lead to bioaccumulation in ecosystems?- a)Natural mineral deposits.
- b)Human activities, such as industrial pollution.
- c)Erosion of rocks.
- d)Plant photosynthesis.
Correct answer is option 'B'. Can you explain this answer?
a)
Natural mineral deposits.
b)
Human activities, such as industrial pollution.
c)
Erosion of rocks.
d)
Plant photosynthesis.
 | Edgy Education answered |
Human activities, such as industrial pollution, are the primary sources of toxins that lead to bioaccumulation in ecosystems, introducing harmful substances into the environment.
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