Question

Indicate whether each of the following descriptions applies to myosins (M), kinesins (K), or dyneins (D). Your answer would be a five-letter string composed of letters M, K, and D only, e.g. MMMDD.

(A) They have larger structures than the other two.
(B) They are generally faster than the other two.
(C) They are structurally unrelated to the other two.
(D) They walk on a different cytoskeletal filament than the other two.
(E) They are all minus-end directed.

Answer 1

In Myosins (M), Kinesins (K), and Dyneins (D), the descriptors align as follows:

(A) Myosins generally have larger structures.

(B) Kinesins are generally faster.

(C) Dyneins are structurally unrelated.

(D) Dyneins walk on different cytoskeletal filaments.

(E) Dyneins are all minus-end directed.

Step-by-step explanation:

Myosins (M), kinesins (K), and dyneins (D) are motor proteins involved in intracellular transport and movement along cytoskeletal filaments. Myosins, responsible for muscle contraction among other functions, tend to have larger structures, making them suitable for the powerful contractile forces in muscle cells (A). Kinesins, often involved in moving cargo towards the plus-end of microtubules, are generally faster in their movement compared to myosins and dyneins (B).

Dyneins, on the other hand, exhibit structural dissimilarity from myosins and kinesins (C). They participate in retrograde transport along microtubules, moving towards the minus-end. This distinguishes dyneins from both myosins and kinesins (D). Additionally, dyneins are known for their minus-end-directed movement, making them unique in this aspect (E).

In summary, the final answer MKDMD accurately reflects the distinctive features of myosins, kinesins, and dyneins based on size, speed, structure, filament preference, and directionality of movement.