Answer:
carbohydrate
Explanation:
glucose is a kind of carbohydrate.
Answer:
I think the answer is b
Explanation:
b The trilobite and blue crab both share the same ancestor population that had a biramous limb. They inherited this structure from the ancestor population. c All species have their own specific body structures, so it is a coincidence that this trilobite and blue crab each happen to have the biramous limb structure.
Answer:
See explanation below.
Explanation:
Starfish, also known as sea stars, are marine organisms that belong to the Class Asteroidea. They are considered invertebrates because they lack a vertebral column. Moreover, most starfish species have five arms but some species can have up to 15!
Here are some characteristics that differentiate starfish from other organisms and make them so unique:
- Possession of tube feet.
- Most species have pedicellaria, claw-shaped structures with movable jaws.
- Radial symmetry
- They can possess from 5 to 15 arms.
- Do not possess brain.
- They can regenerate parts of their body.
Microfilaments
Microfilaments are fine, thread-like protein fibers, 3-6 nm in diameter. They are composed predominantly of a contractile protein called actin, which is the most abundant cellular protein. Microfilaments' association with the protein myosin is responsible for muscle contraction. Microfilaments can also carry out cellular movements including gliding, contraction, and cytokinesis.
Microtubules
Microtubules are cylindrical tubes, 20-25 nm in diameter. They are composed of subunits of the protein tubulin--these subunits are termed alpha and beta. Microtubules act as a scaffold to determine cell shape, and provide a set of "tracks" for cell organelles and vesicles to move on. Microtubules also form the spindle fibers for separating chromosomes during mitosis. When arranged in geometric patterns inside flagella and cilia, they are used for locomotion.
Hope this helps :)