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The correct answer is D. (2) - The cell membrane is a partially permeable structure, and in this case, it is plasmolysed, meaning it has shrunk away from the cell wall.

The correct answer is D. Cell X is a xylem cell. Xylem vessels primarily transport water and minerals. They do not contain reducing sugars like glucose. Therefore, the test with Benedict's reagent would be negative. Moreover, Xylem vessels do not store starch. Thus, the iodine test would also be negative. So, the results would be negative for both Benedict's and iodine.

The correct answer is D. Cell membrane, Cytoplasm and nucleus are found in both the animal and plant cells.

The correct answer is C. Starch is stored in the chloroplasts, this part of the plant cell will appear blue-black when iodine solution is used. The Iodine solution is used to test for starch. In bright sunlight, plant cells perform photosynthesis and produce glucose. Any excess glucose is stored as starch, which is found in the chloroplasts. When iodine is applied, it reacts with the starch and turns it blue-black. A is incorrect because the nucleus holds DNA and regulates cell functions, but it does not store starch. B is also incorrect because the cell wall is not stained by iodine because it does not contain starch. The cell wall is made up of cellulose, which is a type of carbohydrate that does not react with iodine. D is also incorrect because the sap vacuole store various substances but do not store starch in this case.

The correct answer is A. The cell membrane in living cells is the primary structure that prevents the red stain from entering, which is why dead cells, lacking this barrier, absorb the stain. Living cells possess an intact cell membrane that serves as a selectively permeable barrier, controlling the movement of substances in and out of the cell. Upon cell death, this membrane loses its selective permeability, allowing the red stain to enter the cells and cause them to appear red. B is incorrect because while plant cells have a cell wall for structural support, it is not the main barrier preventing the stain from entering. C is also incorrect because the cytoplasm, a gel-like substance within the cell, does not act as a barrier. D is incorrect because vacuole are storage organelles, but they do not function as barriers.

D

B is the correct answer. Cell wall is freely permeable while cell membrane is partially permeable.

D is the correct answer. Plants cell wall is made up of cellulose. Animal cells do not have a cell wall. Bacterial cell wall is made up of peptidoglycen while the fungi cell wall is made up of chitin.

A is the correct answer. It is a eukaryotic cell which can not be a bacterial cell, and has a single outer boundary that represents the cell membrane therefore, it's an animal cell as it's outermost layer is the cell membrane.

A is the correct answer. Cell membrane, nucleus and the cytoplasm are found in both the animal and plant cells.

B is the correct answer. It is a mesophyll cell because it contains chloroplasts, which are responsible for photosynthesis. In contrast, epidermal cells lack chloroplasts, root hair cells have long extensions, and xylem vessels are hollow tubes. Therefore, it is a mesophyll cell of a leaf.

Good effort

lol the dislike button is covering the third cell

The correct answer is option C. This is because both sperm cells (2) and red blood cells (3) are found in animal cells. Option A is incorrect because root hair cells (1) are found in plants, not animals, although sperm cells (2) are present in animals. Option B is also incorrect because while red blood cells (3) are found in animals, root hair cells (1) are not. Option D is incorrect because it falsely claims that all of the cells are present in animals, while root hair cells (1) are only found in plants. Thus, option C is the correct choice.

C

The correct answer is B, as both the cell wall (1) and chloroplasts (3) are absent in animal cells. Option A is incorrect because, while the cell wall (1) is not found in animal cells, it incorrectly pairs with the cell membrane (2), which is present in animal cells. Option C is also incorrect, as both the cell membrane (2) and nucleus (4) are present in animal cells. Option D is incorrect as well, because, although the sap vacuole (5) is not present in animal cells, it is paired with the cell membrane (2), which is present in animal cells. Therefore, Option B is the correct answer.

The correct answer is B. Option A is incorrect because the outermost layer in a plant cell is the cell wall. Option C refers to the cytoplasm. Option D refers to the sap vacuole. Therefore, the correct answer is B: a thin layer that surrounds the cytoplasm, located on the inner side of the cell wall, and is partially permeable.

The correct answer is: D (tissue) A cell is the basic unit of life, while an organ is a group of tissues working together to perform a specific function. An organ system consists of organs working together for a common purpose, and tissue refers to a group of cells working together for a particular function. In the photomicrograph, we observe a layer of tightly packed cells that cover the surface of the onion. This layer is called the epidermis, which is a type of tissue. Therefore, the correct answer is D. tissue.

The correct answer is : C Chloroplasts, found in plant cells, are located in the cytoplasm around the nucleus. Diagram C is correct because it accurately places the chloroplasts in the cytoplasm around the nucleus. Diagram A incorrectly shows the nucleus placed inside the sap vacuole. Diagram B incorrectly places the chloroplasts inside the sap vacuole. Diagram D shows that the chloroplasts are located within animal cell, which is impossible. Thus, Diagram C is the correct choice.

O Level Biology 5090 topical (Chapter 1 : Cells) notes are available here: drive.google.com/file/d/1qkMuF-Kpt-Kj4sBcd6KJkpH1Ah3W5J_F/view?usp=drivesdk

O Level Biology 5090 topical (Chapter 1 : Cells) notes are available here: drive.google.com/file/d/1qkMuF-Kpt-Kj4sBcd6KJkpH1Ah3W5J_F/view?usp=drivesdk