Aquatic Ecosystem

Q.

Difference between aquaculture and pisciculture.

Q.

Question 21

Write the adaptation in aquatic plants due to which

(a) submerged leaves can bend in the flowing water.

(b) leaves can float on the surface of water.

Q.

Write any two adaptive features of fish.

Q.

Psammophytes are plants growing on ____________ type of soil.

1. Sandy

2. Acidic

3. Alkaline

4. Alluvial

Q.

How does the photic zone differ from the aphotic zone?

Q.

What do you understand by composite fish culture?

Q.

Rearing and breeding of fish in pound, tanks and artificial reservoirs is called:

1. Aquaculture

2. Fishing

3. Pisciculture

4. Apiculture

Q.

Give impotance of the following:

1. Mariculture.

2. Aquaculture.

3. Composite fish farming.

Q. The main adaptations that give hydrilla an advantage over other native plants are:

1. It can grow at low light intensities.
2. Stomata are present on the upper surafce of the leaves.
3. It can propagate sexually and asexually.
4. It is able to store nutrients for later use.

Q. Write the effect of temperature on the organisms adapted in a lake and pond in a tabular form.

Q. Match the freshwater zones with their inhabitants.

$\begin{array}{ccc}\text{Column I}& \text{Column II}& \text{Column III}\\ \text{(1) Littoral zone}& \text{(a) Dimly lit zone}& \text{(i) Fast swimmers}\\ \text{(2) Limnetic zone}& \text{(b) Shallow zone}& \text{(ii) Floating plants}\\ \text{(3) Profundal zone}& \text{(c) Open water zone}& \text{(iii) Heterotrophs}\end{array}$

1. 1-b-i; 2-c-ii; 3-a-iii
2. 1-c-ii; 2-b-i; 3-a-iii
3. 1-a-i; 2-b-iii; 3-a-ii
4. 1-c-iii; 2-a-ii; 3-b-i

Q.

Correct the following statement.

Culture fishery in freshwater is known as composite culture.

Q.

Mention the adaptations shown by aquatic animals.

Q.

Give some examples of compatible fish species used in composite fish farming.

Q. Plants that are growing in water are called ................

Q. Animals and plants living in surface waters have access to:

1. More nutrients
2. High temperature
3. High pressure
4. More light

Q. Planktons have small oil droplets in their cells which keep them floating.

1. True
2. False

Q.

In which type of habitat would you most likely find xerophytes?

1. Forest

2. Desert

3. Marsh

4. Tundra

Q. This is a dark and cold oceanic zone with no photosynthetic activity. Marine animals seen here are blind and shows bioluminescence. Identify the zone.

1. Euphotic zone
2. Abyssal zone
3. Bathyal zone
4. Profundal zone

Q. The yellow tang is a marine fish with lesser salt content in their bodies than the seawater. Thus fluid could be drained out of the body into the sea due to difference in salinity. This could be dangerous and fatal to the organism. How do they manage to survive in such conditions?

1. The respiration rate increases.
2. They accumulate more salts in their body.
3. They excrete large amounts of water.
4. They drink large amounts of water.

Q.

Question 2
What are the advantages of composite fish culture?

Q.

Practice of culturing marine fish is known as:

1. Pisciculture

2. Sericulture

3. Mariculture

4. Aquaculture

Q. In sea water, the salt concentration (measured as salinity in parts per thousand) _________________.

1. 30 - 35
2. 10 - 20
3. 10 15
4. 50 60
5. 50 6060 70

Q. Assertion :Most marine animals find it difficult to live in fresh water and vice versa. Reason: Some animals can tolerate a narrow salinity range while others can bear a wide salinity range.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Match the oceanic zones with their inhabitants.

$\begin{array}{ccc}\text{Column I}& \text{Column II}& \text{Column III}\\ \text{(1) Sunlit zone}& \text{(a) Abyssal zone}& \text{(i) Corals}\\ \text{(2) Twilight zone}& \text{(b) Euphotic zone}& \text{(ii) Angler fish}\\ \text{(3) Dark zone}& \text{(c) Bathyal zone}& \text{(iii) Planktons}\end{array}$

1. 1-b-iii; 2-c-i; 3-a-ii
2. 1-c-ii; 2-b-i; 3-a-iii
3. 1-a-i; 2-b-ii; 3-a-iii
4. 1-c-i; 2-a-iii; 3-b-ii

Q. Which of the following statement(s) is/are true regarding air breathing, surface dwellers?

(i) Underwater pressure let their lungs collapse.
(ii) Collapsed lung can make them float on water.
(iii) Oxygen is stored in the muscle tissues.

1. (i) and (iii) are true
2. (ii) and (iii) true
3. (i), (ii), and (iii) are true
4. only (ii) is true

Q. Many fresh water animals cannot live for long in sea water mainly because of

1. Change in the atmosphere
2. Change in level of thermal tolerance
3. Variation in light intensity
4. Osmotic problems they would face
5. Change in temperature and light

Q. Which of the following statement(s) is/are true regarding air breathing, surface dwellers?

(i) Underwater pressure let their lungs collapse.
(ii) Collapsed lung can make them float on water.
(iii) Oxygen is stored in the muscle tissues.

1. (i) and (iii) are true
2. (ii) and (iii) true
3. (i), (ii), and (iii) are true
4. only (ii) is true

Q. Phytoplanktons are dominant in which of the following zone?

1. Profound zone
2. Limnetic zone
3. Littoral zone
4. Benthic zone

Q. Match the oceanic zones with their inhabitants.

$\begin{array}{ccc}\text{Column I}& \text{Column II}& \text{Column III}\\ \text{(1) Sunlit zone}& \text{(a) Abyssal zone}& \text{(i) Corals}\\ \text{(2) Twilight zone}& \text{(b) Euphotic zone}& \text{(ii) Angler fish}\\ \text{(3) Dark zone}& \text{(c) Bathyal zone}& \text{(iii) Planktons}\end{array}$

1. 1-c-ii; 2-b-i; 3-a-iii
2. 1-b-iii; 2-c-i; 3-a-ii
3. 1-a-i; 2-b-ii; 3-a-iii
4. 1-c-i; 2-a-iii; 3-b-ii