Explanation

a.

(b)

i.black fur and short tail-0

ii. brown fur and long tail-0

iii. black fur and long tail-16

iv. brown fur and short tail-0

(c)

i.Pollen grain: 10

ii. Guard cell: 20

iii. Ovule: 10

iv. Root cell: 20

Correct Answer: A. placenta

Correct Answer: D. sedimentation

Correct Answer: C. Enzymes work best only at certain temperatures.

Explanation

Enzymes have an optimal temperature, or best temperature that they work at. If that temperature is below or above its optimal temperature, the enzyme will decrease in activity; if the temperature change is great enough, the enzyme could even denature (no longer work).

Correct Answer: D) Snake

Explanation

The question is asking us to identify which of the listed organisms lacks chaetae, tentacles and antennae. Chaetae are stiff hairs or bristles, tentacles are elongated structures that arise from the head of certain animals, and antennae are paired sensory appendages located on the heads of most arthropods and some other animals. Option A, the snail, has tentacles, but lacks chaetae and antennae. Option B, the earthworm, has chaetae but lacks tentacles and antennae. Option C, the millipede, has chaetae but lacks antennae and tentacles. Therefore, the correct answer is option D, the snake, because it lacks all three features: chaetae, tentacles and antennae. Snakes are reptiles and do not possess any of these structures. Understanding the structures of different organisms is an important aspect of biology. It helps us to identify and classify different organisms based on their physical characteristics and to understand how they are adapted to their environments.

Correct Answer: B. affords protection from predation for the young fish

Correct Answer: D) food web

Explanation

This Biology question is asking about a form or pattern of feeding relationships. The question wants us to identify the correct term that describes this interlocking pattern. The options given are food chain, nutrition, consumer, and food web. The interlocking pattern of feeding relationships is called a food web. A food web is a more complex way of showing feeding relationships than a food chain. It consists of many interconnected food chains that show how different organisms in an ecosystem are connected through their feeding habits. For example, a food web may show how a grasshopper eats plants, how a bird eats the grasshopper, and how a fox eats the bird. This way, we can see how different organisms are linked and how energy flows through the ecosystem. Therefore, the correct answer to this question is option D, food web. Option A, food chain, is a related term, but it does not describe the interlocking pattern of feeding relationships as comprehensively as a food web. Options B and C, nutrition and consumer respectively, are not related to the question being asked. In summary, a food web is the correct term that describes the interlocking pattern of feeding relationships in an ecosystem. To learn more about this, please read the relevant sections of the recommended textbooks.

Correct Answer: C. ll,lll and lV

Correct Answer: D) The dorsal fin

Explanation

The fins are composed of bony spines protruding from the body with skin covering them and joining them together. Fins are used for movement, stability, nest-building, spawning, and as organs of touch. They can be single or paired. The caudal or tail fin is used for propulsion. Fish that have forked caudal fins usually are fast swimmers. The anal fin stabilizes the fish and provides propulasion while it is swimming. Ventral fins are also used to provide stability in swimming. The paired pectoral fins are used for manoeuvering the fish. The single dorsal fin helps balance the fish while swimming and also during sudden movements or turns. The rays of this fin are often sharp, and a spine is often present.

Correct Answer: A. I, II and III