Question

select all that apply
select all correct statements regarding the structure of archaella.

□ archaella are hollow.

□ archaella are composed of multiple types of archaellin subunits.

□ archaella structure is identical to that of bacterial flagella.

□ archaella are thinner than bacterial flagella.

Explanation:

• Archaella are not hollow (bacterial flagella are hollow, archaella are not).
• Archaella are composed of a single type of archaellin subunit (not multiple), so this is incorrect.
• Archaella structure is different from bacterial flagella (e.g., in composition, assembly, and lack of hollow structure), so this is incorrect.
• Archaella are thinner than bacterial flagella (bacterial flagella are typically thicker, archaella have a slimmer structure). Also, archaella are not hollow (so the first option is wrong), archaella have one type of archaellin (so the second is wrong), and structure is not identical (third wrong). The correct one is "Archaella are thinner than bacterial flagella" and also, wait, correction: Wait, re - checking: Archaella: they are not hollow (so first option wrong), they are composed of a single archaellin subunit (so second option wrong), their structure is different from bacterial flagella (third wrong), and they are thinner than bacterial flagella (fourth correct). Wait, but also, is there another? Wait, no, let's re - verify:

1. Archaella are hollow: False. Bacterial flagella are hollow, archaella are not.
2. Archaella are composed of multiple types of archaellin subunits: False. They are composed of a single (or few, but generally a single major) archaellin subunit.
3. Archaella structure is identical to that of bacterial flagella: False. They differ in composition, assembly, and lack of hollow core.
4. Archaella are thinner than bacterial flagella: True. Bacterial flagella have a larger diameter (around 20 nm), archaella are thinner (around 10 - 14 nm).

Wait, but maybe I made a mistake. Wait, another point: Are archaella composed of multiple archaellin subunits? No, usually a single type (or a few, but the statement says "multiple types" which is incorrect). So the correct statements are "Archaella are thinner than bacterial flagella". Wait, but maybe the first option: No, archaella are not hollow. So the correct one is the fourth option. Wait, but let's check again.

Wait, some sources: Archaella (archaeal flagella) are thinner than bacterial flagella. Bacterial flagella are hollow, archaella are not. Archaella are made of archaellin, usually a single type (so "multiple types" is wrong). Structure is not identical. So the correct statement is "Archaella are thinner than bacterial flagella". Also, is there any other? Wait, no. So the correct option is the fourth one: "Archaella are thinner than bacterial flagella". Wait, but maybe I missed. Wait, no, the first is wrong, second wrong, third wrong, fourth correct.

Answer:

D. Archaella are thinner than bacterial flagella