Where is the site of cellular respiration in eukaryotic cells?

Correct Answer: C

Rationale: The correct answer is C: Mitochondria. Mitochondria are often referred to as the powerhouse of the cell because they are responsible for cellular respiration in eukaryotic cells. During cellular respiration, mitochondria generate energy in the form of ATP. Choices A, B, and D are incorrect. The nucleus is the organelle that houses the cell's genetic material, chloroplasts are responsible for photosynthesis in plant cells, and ribosomes are involved in protein synthesis, not cellular respiration.

Correct Answer: C

Rationale: The cytoskeleton is the correct answer. It provides structural support to the cell, helps maintain its shape, and enables it to adapt to different environments. Microfilaments are part of the cytoskeleton, but they alone do not encompass the entire cytoskeleton's functions. Cytoplasm is the fluid inside the cell where organelles are suspended and is not directly responsible for maintaining cell shape. Centrioles are involved in cell division and do not primarily contribute to maintaining the cell's shape and adaptation.

Correct Answer: C

Rationale: The correct answer is C: '4'. Mitosis consists of four phases: prophase, metaphase, anaphase, and telophase. These phases are crucial in the orderly division of the cell's genetic material. Choice A is incorrect because mitosis is a more complex process involving multiple phases. Choice B is incorrect as it is one phase short of the total phases in mitosis. Choice D is incorrect as mitosis does not consist of five phases.

Correct Answer: B

Rationale: The correct answer is B: Vacuoles (contractile). Vacuoles (contractile) are responsible for expelling excess water out of the cell. Lysosomes are involved in the digestion and removal of waste materials, mitochondria are the powerhouse of the cell involved in energy production, and the nucleus contains the cell's genetic material but does not play a role in pushing water out of the cell.

Correct Answer: B

Rationale: The slide is typically placed on the stage of a microscope. The stage is the platform where the slide containing the specimen is positioned for viewing. The eyepiece is where you look through to view the specimen, the focus knob is used to sharpen the image, and the objective lens is responsible for magnification. Therefore, the correct answer is the stage.

Correct Answer: B

Rationale: Ribosomes are the organelles involved in the synthesis of proteins. They are the cellular machinery responsible for translating mRNA into proteins, making them essential for cell function and structure. The other organelles listed, such as the Endoplasmic Reticulum, Lysosomes, and Vacuoles, have different functions unrelated to protein synthesis. The Endoplasmic Reticulum plays a role in protein processing and transport, Lysosomes are involved in digestion and waste removal, and Vacuoles are responsible for storage and maintaining cell turgor pressure.

Correct Answer: C

Rationale: Correct! Plant cells have vacuoles that serve as storage centers, help in waste disposal by containing and isolating harmful materials, and contribute to protection by storing toxic substances. The other choices are incorrect because the nucleus contains genetic material, mitochondria are responsible for energy production, and ribosomes are involved in protein synthesis.

Correct Answer: B

Rationale: Microtubules are the cellular structures responsible for cell movement and propulsion. Microtubules are part of the cytoskeleton and play a crucial role in various cellular processes, including cell motility and intracellular transport. While microfilaments also contribute to cell movement by enabling muscle contraction and cell shape changes, they are not primarily responsible for propelling the cell. Flagella and cilia are cellular appendages involved in cell movement, but they are composed of microtubules, making them the structures that move due to the actions of microtubules.

Correct Answer: C

Rationale: The correct answer is C: Lipids. Plasma membranes are primarily composed of lipids, specifically phospholipids, which form a lipid bilayer. While proteins are also an essential component of plasma membranes, they are not the primary constituent. Carbohydrates are present on the outer surface of the membrane but are not the main structural component. Nucleotides are the building blocks of nucleic acids like DNA and RNA and are not the main constituents of plasma membranes.