Correct Answer: C. cell membrane

Correct Answer: C. cataract

Correct Answer: D) Oxygen

Explanation

Photosynthesis is the process by which plants make their food. It is a complex process that requires different resources. The question is asking which of the options is not necessary for photosynthesis. Option A is water. Water is a vital component of photosynthesis as it is involved in the light-dependent reactions. In these reactions, water is split into oxygen and hydrogen ions. Therefore, Option A is not the correct answer. Option B is chlorophyll. Chlorophyll is a green pigment found in the chloroplasts of plants that absorbs light energy during photosynthesis. Since chlorophyll is directly involved in capturing light energy, it is also necessary for photosynthesis. Therefore, Option B is not the correct answer. Option C is sunlight. Sunlight is the primary source of energy for photosynthesis. It provides the energy that is needed for the light-dependent reactions. Therefore, Option C is not the correct answer. Option D is oxygen. Oxygen is a by-product of photosynthesis, and it is released into the atmosphere. Plants do not need oxygen for photosynthesis. Therefore, Option D is the correct answer. In conclusion, the option that is not necessary for photosynthesis is Option D, which is oxygen.

Correct Answer: C) Iodine

Explanation

This question is asking which substance is likely to be missing from the diet of a person with goiter. Goiter is a condition where the thyroid gland in the neck becomes enlarged. The thyroid gland produces hormones that regulate metabolism, growth, and development. Out of the options given, the correct answer is Option C: Iodine. Iodine is an essential mineral that the thyroid gland needs to produce hormones. Without enough iodine, the thyroid gland cannot produce enough hormones, which can lead to goiter. Potassium, calcium, and sodium are also important minerals that the body needs, but they are not directly related to the development of goiter. However, having a balanced diet that includes these minerals is important for overall health. To prevent goiter, it is important to consume enough iodine-rich foods such as fish, seaweed, dairy products, and iodized salt. If someone is diagnosed with goiter, they may need to take iodine supplements or medication to regulate their thyroid hormone levels. In summary, the substance likely to be deficient in the diet of a person having goiter is iodine.

Correct Answer: B. transpiration and guttation

Correct Answer: C. littoral zone

Correct Answer: D. Producers ? consumers ? decomposers

Correct Answer: B. contraction and relaxation

Correct Answer: D) Anabaena

Explanation

This question is asking which of the given green algae is not a colonial form. The options are A) Gonium, B) Volvox, C) Pandorina, and D) Anabaena. To begin with, colonial forms of green algae refer to a group of algae that exist as a cluster of cells attached to one another. Out of the options given, Gonium, Volvox, and Pandorina are colonial forms of green algae, while Anabaena is not. Anabaena is a type of cyanobacteria, which is a type of bacteria that can carry out photosynthesis. Unlike colonial forms of green algae, Anabaena exists as a filamentous chain of cells. In summary, the correct answer to this question is option D, Anabaena, because it is not a colonial form of green algae. It is important to note the differences between colonial forms of green algae and other types of organisms that can carry out photosynthesis, such as cyanobacteria.

Correct Answer: B. Birds