Answer:
They are thick, strong and made up of thousands of tubulin which are spiral in shape.
Explanation:
In eukaryotic cells, they have microtubules which are fibres serving as tracks for cell to cell transport and regulate the shape of a cell.
Microtubules are different from other cytoskeletal filaments because they possesses a cylindrical shape with the tube having a larger diameter of 20-25 nm as compared to microfilament that have a diameter of 3-6 nm.
Microtubules are made of subunits of proteins called tubulin named alpha and beta that is not present in other cytoskeletal filaments.
Answer:
It is called mimicry when a living thing copies the appearance of another living thing as a means of protection.
Explanation:
Mimicry is used primarily by living things as a means for protection and to decrease the chances of the living thing being killed. For example, a frog that is prey to a toad could have bright colors (bright color frogs are often poisonous) that don't mean anything to the frog and it's species, but to the toad, the frog is poisonous and should not be eaten, so the toad does not eat the frog because it is brightly colored.
Without mimicry, the frog would have been eaten because it wouldn't have had looked like a poisonous frog, or something that the toad would avoid.
Answer & explanation:
The cell was discovered in 1669 by the English scientist Robert Hooke when looking at a piece of tissue in a two-lens microscope. Hooke was able to visualize small cavities in the experiment piece, then naming such cell cavities.
Only a century and a half after the discovery of the cell, that the Cell Theory was launched, replacing the theory of spontaneous generation (or abiogenesis).
Before that, many scientists were already busy understanding the structure and functioning of the cell, generating knowledge that became fundamental to the development of biology, specifically cytology, a branch of science that studies the structure, functions and development of cells.
Answer:
Environmental factors such as diet, temperature, oxygen levels, humidity, light cycles, and the presence of mutagens can all impact which of an animal's genes are expressed, which ultimately affects the animal's phenotype.
Explanation:
In 1969, whittaker proposed moving the prokaryotes from the kingdom plantae to a separate kingdom due to structural and metabolic differences.