Nokea
What is the meaning of exocytosis?
- A. The cell engulfs and brings in substances.
- B. The cell releases content outside by fusing with the plasma membrane.
- C. The cell engulfs liquid material.
- D. The cell brings in solid particles.
Correct Answer: B
Rationale: Exocytosis is the process by which a cell releases substances to the outside by fusing with the plasma membrane. During exocytosis, vesicles containing molecules fuse with the cell membrane, allowing the release of the contents outside the cell. This process is crucial for the secretion of various substances such as hormones, enzymes, and neurotransmitters. Choices A, C, and D are incorrect as they describe processes different from exocytosis. Choice A describes endocytosis, where the cell engulfs substances to bring them into the cell. Choice C is more aligned with pinocytosis, the process of engulfing liquid material. Choice D refers to phagocytosis, which is the uptake of solid particles by the cell.
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The dorsal body cavity is _______ to the ventral body cavity.
- A. medial
- B. deep
- C. posterior
- D. anterior
Correct Answer: C
Rationale: The dorsal body cavity is positioned on the back (posterior) side of the body, whereas the ventral body cavity is on the front (anterior) side. Therefore, the dorsal body cavity is posterior to the ventral body cavity. Choice A, 'medial,' refers to a position toward the midline, not the back or front. Choice B, 'deep,' is a term used to describe structures that are further away from the surface, not their position in relation to each other. Choice D, 'anterior,' is the opposite of 'posterior' and refers to the front side of the body, not the back.
Which is a secondary defense for the body against pathogens?
- A. Tears
- B. Urine
- C. Inflammation
- D. Mucus
Correct Answer: C
Rationale: Inflammation is a secondary defense mechanism for the body against pathogens. When tissues are injured or infected, inflammation occurs as a protective response involving increased blood flow, white blood cell migration, and tissue repair. This process helps contain and eliminate pathogens, preventing them from spreading further in the body. Tears (Choice A) are a primary defense containing lysozyme and other antimicrobial agents. Urine (Choice B) is typically considered a non-specific defense mechanism due to its flushing action in the urinary tract. Mucus (Choice D) acts as a physical barrier and traps pathogens, also considered a primary defense mechanism.
What is the function of amylase?
- A. Breaking down starch
- B. Digesting fat
- C. Breaking down protein
- D. Absorbing water
Correct Answer: A
Rationale: The correct answer is A: Breaking down starch. Amylase is an enzyme that specifically functions to break down starch into smaller sugar molecules such as maltose and glucose. This process is essential for the digestion and absorption of carbohydrates in the body. Choices B, C, and D are incorrect because amylase does not digest fat, break down protein, or absorb water; its primary function lies in starch digestion.
How does a transverse section divide the body?
- A. Into right and left regions
- B. Into upper and lower regions
- C. Into front and back regions
- D. Between the dorsal and ventral cavities
Correct Answer: B
Rationale: A transverse section, also known as a cross-section, divides the body into upper and lower regions. This type of section cuts across the body horizontally, creating a division between the superior (upper) and inferior (lower) portions of the body. Choice A is incorrect as dividing the body into right and left regions is typically done by a sagittal section. Choice C is incorrect as dividing the body into front and back regions is usually achieved by a frontal section. Choice D is incorrect as it refers more to the relationship between dorsal and ventral cavities rather than the actual division of the body.
What is the meaning of endocytosis?
- A. The cell engulfs solid particles.
- B. The cell engulfs liquid material.
- C. The cell expels solid particles.
- D. The cell releases liquid material.
Correct Answer: A
Rationale: Endocytosis is a cellular process where the cell engulfs and internalizes solid particles by forming vesicles. It is a mechanism used for nutrient uptake, cell signaling, and maintaining cellular homeostasis. Options B, C, and D describe processes that are opposite to endocytosis. Choice B is incorrect because it describes pinocytosis, which is the process of engulfing liquid material. Choice C is incorrect as it describes exocytosis, the process of expelling material from the cell. Choice D is incorrect as it describes the process of releasing liquid material from the cell. Therefore, the correct answer is A.