1. Which of following is classified as a long bone?
A. Carpal
B. Rib
C. Tibia Correct
D. Vertebrae
Explanation
Long bones are characterized by a length greater than their width and include bones like the tibia in the leg. The carpal bones are short, ribs are flat, and vertebrae are irregular. Thus, the tibia is the correct choice.
2. A person hyperventilates if the blood level of which of the following dissolved gases is abnormally low?
A. Carbon monoxide
B. Carbon dioxide Correct
C. Hydrogen
D. Nitrogen
Explanation
Hyperventilation occurs when blood carbon dioxide levels drop, causing a rise in blood pH. This triggers rapid breathing to restore balance. Other gases like carbon monoxide or nitrogen do not directly cause this response.
3. Which of the following is the term for the gap between two nerve cells?
A. A myelin sheath
B. A dendrite
C. An axon
D. A synapse Correct
Explanation
The synapse is the gap between two nerve cells where neurotransmitters are released to transmit signals. Myelin sheaths insulate axons, dendrites receive signals, and axons conduct signals, but none are the gap itself.
4. Which of the following structures is present in both prokaryotic and eukaryotic cells?
A. Chloroplast
B. Golgi apparatus
C. Cell membrane Correct
D. Endoplasmic reticulum
Explanation
Both prokaryotic and eukaryotic cells have a cell membrane that regulates substance movement. Chloroplasts, Golgi apparatus, and endoplasmic reticulum are exclusive to eukaryotic cells, making the cell membrane the correct answer.
5. Which of the following types of membrane is associated with the skin?
A. Peritoneum
B. Synovial
C. Serous
D. Cutaneous Correct
Explanation
The cutaneous membrane is the skin itself, consisting of epithelial and connective tissue layers. Peritoneum lines abdominal organs, synovial membranes are in joints, and serous membranes cover internal organs, not the skin.