Correct Answer: B. holophytic

Correct Answer: D. Spirogyra

Correct Answer: A. father's sex cells

Correct Answer: B. A small number of humans form an isolated colony on a deserted island.

Explanation

The founder effect is when genetic variability is lost due to a small number of individuals from a larger population forming a new population. The smaller population only breeds with each other and is not genetically representative of the larger group from which it was founded. Thus, the humans on a deserted island are an example of this. The hurricane might be an example of a population bottle neck and the breeder might be causing a population bottleneck by only breeding certain dogs, but the humans are a better example of the deliberate formation of a new breeding population.

Correct Answer: C) Euglena sp.

Explanation

Photosynthesis is a process by which green plants and some other organisms use sunlight, carbon dioxide, and water to produce oxygen and glucose. The question is asking which animal is photosynthetic. Among the options given, the correct answer is option C - Euglena sp. Euglena is a unicellular organism that belongs to the kingdom Protista. It is unique because it can produce its food through photosynthesis like plants and can also feed on other organisms like animals. Euglena contains chloroplasts, which are organelles that are responsible for photosynthesis in plants. These chloroplasts contain a green pigment called chlorophyll, which absorbs light energy used during photosynthesis. Paramecium and Amoeba are also unicellular organisms, but they do not possess chloroplasts and cannot carry out photosynthesis. Hydra is a multicellular organism that belongs to the phylum Cnidaria, and like Paramecium and Amoeba, it cannot carry out photosynthesis. In summary, Euglena sp. is the only photosynthetic animal among the options given. It can carry out photosynthesis due to the presence of chloroplasts with chlorophyll.

Correct Answer: A. brain

Explanation

(a) Functions of the mammalian skeleton include:

(I) Supports it posture and provides to the body e.g. backbones/ vertebrae/pelvic girdle

(ii) It gives protection — e.g. ribcage protects heart/lungs/cranium(skull) protects brain/vertebrae protects spinal cord/pelvic girdle protects female reproductive organs.

(iii) The skeleton helps in the production of blood cells — in the bone/marrow of the long bones

(iv) Storage of calcium is also encourage, e.g., in the bone matrix

(v) Movement/locomotion is enhanced. — any of the limb bones

(vi) Breathing movements — Riles

(vii) Attachment of muscles is facilitated — any bone

(viii) Provision of shape-axial skeleton/grindles etc

(b) Bones and muscles bring about movement at the elbow in the following ways:

(i) Bicep and tricep act antagonistically to bring about movement at the elbow. The bicep is attached to the scapula and radius; while the tricep are attached to the scapula and ulna

(ii) Bicep contracts while tricep relaxes to cause bending/flexing of the forearm

(iii) Tricep contracts while bicep relaxes to cause straightening of the forearm.

(c) Support in herbaceous and woody Plants can come in different ways:

(i) Herbaceous Plant:

(1) By turgidity, water is preserved

(2) Due to the presence of water, vacuoles inside parenchyma cells/living cells

(3) Thickening of walls of collenchyma cell (at the corners).

(ii) Woody Plant:

(1) Sclerenchyma in the cortex

(2) By the Xylem strengthened by deposits of lignin in their walls

(2) Secondary growth/thickening provides extensive wood / secondary xylem and bark.

(d) The vitamin and mineral element necessary for healthy bone development are:

(1) Vitamin — D/Calciferol, Vitamin C (forms the cement of bow)

(2) Mineral elements — calcium/phosphorus/magnesium.

Correct Answer: D) succession begins only on a bare ground

Explanation

Succession refers to the changes that occur in the species composition, community structure, and function of an ecosystem over time and space. This process is usually set in motion by some sort of disturbance, such as a volcanic eruption, wildfire, or human activity. As a result of this disturbance, organisms that are better suited to the new conditions move in and establish themselves, replacing the previous inhabitants. This process is both directional and predictable, with each stage of succession leading to the next and culminating in a stable, climax community. Option A is a true statement about succession. Option B is also correct in that disturbance is usually necessary to initiate succession. Option C is also true, as succession follows a predictable pattern. Option D, on the other hand, is incorrect. Succession can begin on any type of ground, not just bare ground. For example, secondary succession occurs in areas where the soil has already been formed, but the previous community has been removed, such as after a forest fire. Therefore, Option D is the correct answer to this question. It is important to note that succession is a natural process that occurs over a long period of time and is influenced by many factors, including climate, topography, and biotic interactions. Understanding the process of succession is important for understanding how ecosystems change and adapt over time.

Correct Answer: B. worker

Correct Answer: D) Ant