Correct Answer: B) Food web

Explanation

In Biology, an ecosystem is a community of organisms interacting with their physical environment. An important aspect of any ecosystem is how organisms obtain their food. The feeding pattern in an ecosystem is called the food web. A food web is a diagram that shows how different organisms in an ecosystem are connected through feeding relationships. Option A is incorrect because the pyramid of energy is a graphical representation of the amount of energy that flows through different levels of an ecosystem. Option C, the food chain, is a linear sequence of organisms through which food and energy pass in an ecosystem. Option D, the pyramid of members, is not a recognized term in Biology. Option E, ecology, is the study of how organisms interact with each other and their environment, including their feeding patterns. Therefore, the correct answer to this question is Option B, food web, which is a diagram that shows how different organisms in an ecosystem are connected through feeding relationships.

Correct Answer: C) Enamel

Explanation

Enamel is the hardest substance in the human body and contains the highest percentage of minerals (at 96%), with water and organic material composing the rest. The primary mineral is hydroxyapatite, which is a crystalline calcium phosphate.

Correct Answer: C. presence of gilll clefts in vertebrate embryos

Correct Answer: B) has plant and animal feature

Explanation

Englena is a unicellular organism that is capable of making its own food. This means that it is an autotrophic organism. Autotrophic organisms make their own food through photosynthesis or chemosynthesis. Photosynthesis is the process by which plants, algae, and some bacteria use sunlight to convert carbon dioxide and water into glucose, which serves as food for the organism. Chemosynthesis, on the other hand, is the process by which some bacteria use chemicals to produce their food instead of sunlight. The question is asking why Englena is an autotrophic organism. The correct answer is Option C, which states that Englena can manufacture its food. This means that Englena is capable of producing its own food through the process of photosynthesis, just like plants and some other unicellular organisms. Options A and D are incorrect, as having flagella or moving fast do not necessarily make an organism autotrophic. Option B is also incorrect, as having both plant and animal features does not necessarily make an organism autotrophic either. It is important to understand the concept of autotrophic organisms as it is a fundamental concept in Biology. Autotrophic organisms play a key role in the food chain and ecosystem as they are the primary producers of food. Without them, other organisms would not be able to survive.

Correct Answer: D. heredity

Correct Answer: B. expandable lungs

Correct Answer: B. feeds on already manufactured food

Correct Answer: B) rhizoids

Explanation

In lower plants like mosses, the structure which performs the functions of roots of higher plants is called. The question is asking us to identify the name of this structure from the options given. The options are roots hairs, rhizoids, hyphae, and roots. The correct answer is option B: rhizoids. Rhizoids are thread-like structures that anchor lower plants like mosses to the ground and absorb water and nutrients. They do not have a vascular system like true roots found in higher plants, and therefore, cannot transport water and nutrients to other parts of the plant. It is important to note that although rhizoids may perform similar functions to roots, they are not classified as roots, as they are not true roots. True roots have vascular tissues that transport water, minerals, and nutrients throughout the plant. Understanding the difference between rhizoids and true roots is essential in Biology, as it helps in the classification of plants into different groups based on their characteristics. For more information on plant classification and structures, please see the recommended textbooks.

Correct Answer: D. protein

Correct Answer: B) Increase the mineral salt content.

Explanation

The question is asking about the role of dead organic matter in the soil. Dead organic matter refers to the remains of dead plants and animals that have decomposed and become part of the soil. Option A suggests that the role of dead organic matter is to make the soil black. While it is true that dead organic matter can contribute to the dark color of soil, this is not its primary role in the soil. Option B states that the role of dead organic matter is to increase the mineral salt content of the soil. This is the correct answer. Dead organic matter contains nutrients like nitrogen, phosphorus, and potassium that are essential for plant growth. As the organic matter decomposes, these nutrients are released into the soil, making it more fertile. Option C suggests that dead organic matter provides food for all living organisms. While it is true that dead organic matter can support the growth of microorganisms and other soil organisms, it is not its primary role in the soil. Option D states that the role of dead organic matter is to increase the acidity of the soil. This is incorrect. Dead organic matter tends to have a neutral or slightly acidic pH, and its decomposition does not significantly affect the acidity of the soil. In summary, the correct answer to the question is Option B, which states that the role of dead organic matter in the soil is to increase the mineral salt content. Dead organic matter contains nutrients that are essential for plant growth, and its decomposition releases these nutrients into the soil, making it more fertile.