Nokea
Human cells need oxygen for respiration. What system of the body is responsible for transporting an oxygen molecule to different locations throughout the body?
- A. Skeletal
- B. Lymphatic
- C. Circulatory
- D. Respiratory
Correct Answer: C
Rationale: The circulatory system is responsible for transporting oxygen throughout the body. It consists of the heart, blood vessels, and blood, which work together to deliver oxygen from the lungs to cells and tissues, facilitating cellular respiration. The skeletal system provides structural support and protection for the body but is not involved in oxygen transport. The lymphatic system helps maintain fluid balance and immune function, not oxygen transport. The respiratory system is responsible for gas exchange in the lungs but relies on the circulatory system to transport oxygen to cells and tissues.
You may also like to solve these questions
Which characteristic is true of prokaryotic cells?
- A. Have a nucleus
- B. Have a capsule
- C. Have membrane-bound organelles
- D. Cannot move on their own
Correct Answer: B
Rationale: Prokaryotic cells are characterized by the absence of a nucleus; instead, they have a nucleoid region where the genetic material is located. Prokaryotic cells often have a capsule, a protective layer outside the cell wall that plays a role in protection and adherence to surfaces. While eukaryotic cells have membrane-bound organelles, prokaryotic cells lack these membrane-bound structures. Prokaryotic cells are capable of movement, facilitated by structures like flagella or pili.
Which vitamin is recognized for its healing antioxidant properties?
- A. Vitamin D
- B. Vitamin K
- C. Vitamin A
- D. Vitamin E
Correct Answer: C
Rationale: Vitamin A is well-known for its antioxidant properties, essential for healing, maintaining healthy skin and tissues, and supporting the immune system. It plays a vital role in repairing damaged tissues, making it crucial for overall health and facilitating healing processes.
The cell membrane consists of a bilayer of phospholipids with proteins, cholesterol, and glycoproteins. This bilayer creates a hydrophobic region between two layers of lipids, making it which of the following?
- A. Impermeable
- B. Permeable
- C. Selectively permeable
- D. Selectively impermeable
Correct Answer: C
Rationale: The cell membrane is composed of a phospholipid bilayer with proteins, cholesterol, and glycoproteins. This structure results in the creation of a hydrophobic region between the lipid layers. The cell membrane is termed 'selectively permeable' because it allows certain substances to pass through while restricting the passage of others, based on factors like size and charge. This property is essential for regulating the transport of ions and molecules in and out of the cell to maintain cellular function and homeostasis.
Why do cells require a large surface-to-volume ratio?
- A. For complexity.
- B. Compartmentalization.
- C. Size of organelles.
- D. Nutrient and gas exchange.
Correct Answer: D
Rationale: The correct answer is D: Nutrient and gas exchange. Cells require a large surface-to-volume ratio to efficiently exchange nutrients and gases with their environment. With a larger surface area, cells can absorb more nutrients and oxygen while expelling waste and carbon dioxide more effectively.
Rationale:
1. Nutrient exchange: A larger surface area allows for more nutrient absorption, essential for cell metabolism and function.
2. Gas exchange: A high surface-to-volume ratio facilitates the exchange of gases like oxygen and carbon dioxide necessary for cellular respiration.
3. Efficiency: Cells need to maintain a balance between surface area and volume to ensure optimal nutrient and gas exchange.
4. Other choices:
- A: Complexity is not directly related to the surface-to-volume ratio.
- B: Compartmentalization refers to the organization of organelles within a cell, not the surface-to-volume ratio.
- C: While size of organelles can affect cell function, it is not the primary reason for requiring a
What human tissue allows the body to move?
- A. Connective.
- B. Epithelial.
- C. Muscular.
- D. Nervous.
Correct Answer: C
Rationale: The correct answer is C: Muscular tissue. Muscular tissue is responsible for movement in the body as it contains specialized cells that can contract and relax, generating force to move body parts. Connective tissue (A) mainly provides support and structure, while epithelial tissue (B) functions in protection and absorption. Nervous tissue (D) transmits electrical signals but does not directly contribute to movement like muscular tissue does. Therefore, the correct choice is C as it is the only tissue type directly involved in body movement.