Which of the following terms would be used in the name of a muscle that moves the leg away from the body?

Correct Answer: D

Rationale: Abductor names a muscle moving the leg away from the midline, like gluteus medius abducting the thigh. Flexor (e.g., biceps femoris) bends joints, decreasing angles. Adductor (e.g., adductor longus) pulls the leg inward. Extensor (e.g., quadriceps) straightens joints, not moving laterally. Abduction's outward action aligns with the term, distinguishing it from bending, inward, or straightening motions, key for leg positioning.

Correct Answer: A

Rationale: Gram-negative bacteria possess a unique cell wall with an outer membrane containing lipopolysaccharides (LPS). These LPS molecules, termed endotoxins, are integral structural components released upon cell damage or death, triggering strong immune responses like fever or septic shock. Exotoxins are secreted proteins, not wall components, and 'toxins' is too vague. 'None of the above' ignores LPS's role. Endotoxins' presence in the gram-negative wall, distinct from gram-positive peptidoglycan, and their release mechanism underline their identity as key immunological triggers, differentiating them from secreted toxins.

Correct Answer: D

Rationale: Boiling points depend on intermolecular forces. Glycerol, with three hydroxyl groups, forms extensive hydrogen bonds, requiring more energy to vaporize, yielding a boiling point of 290°C. Water (100°C) has strong hydrogen bonding but fewer sites per molecule. Ethanol (78°C) has one hydroxyl, and ether (34.6°C) relies on weaker dipole forces. Glycerol's multiple bonding sites create stronger attractions, elevating its boiling point, a key factor in its use in high-temperature applications, distinguishing it from less bonded compounds.

Correct Answer: D

Rationale: Bees and butterflies are vital pollinators, transferring pollen between flowers to enable fertilization and seed production in plants like fruits and vegetables. Their absence halts pollination, reducing seed output, as many plants can't self-pollinate effectively. Birds may rely on seeds, but their food need isn't the direct issue. More flowers or seeds contradict pollination's loss. Fewer seeds, a direct consequence, impacts ecosystems and agriculture, highlighting pollinators' critical role in reproduction.

Correct Answer: C

Rationale: A cholinergic receptor, specifically the nicotinic subtype, on the muscle fiber's sarcolemma binds acetylcholine, opening Na⁺ channels to depolarize and contract the muscle. Adrenergic receptors (alpha/beta) bind catecholamines (e.g., norepinephrine) in smooth muscle or cardiac contexts, not skeletal. Beta receptors, a subset, are irrelevant here. Tyrosine kinase receptors (e.g., for growth factors) don't mediate neurotransmitter action. Cholinergic receptors' specificity for acetylcholine distinguishes them, critical for skeletal muscle excitation, unlike adrenergic or signaling receptors.