Answer:
Chromatin is a substance within a chromosome consisting of DNA and protein. The DNA carries the cell's genetic instructions. The major proteins in chromatin are histones, which help package the DNA in a compact form that fits in the cell nucleus. Changes in chromatin structure are associated with DNA replication and gene expression.
Explanation:
Answer:
The Z lines and H- zone shortens during the muscle contraction.
Explanation:
Sarcomere is the area between the two Z lines. The Z- lines are present in the centre of I - band and H - zone is present in the A - band. The actin filaments which are thin filaments present in I- band and contracts, slide over the myosin filament during contraction.
The I - band, H- zones are became shortens as they are thin than the A- band. It is anisotropic band having thick myosin filaments. They are not flexible and remain in its constant shape during the muscle contraction.
After the muscle contraction, the A- band and the H- zone comes to their original shape. In other words, the sarcomere shortens and comes back during muscle contraction, and relaxation.
Answer:
d. introduce native flowering plants the adult butterflies need for nectar, their main food.
Explanation:
Organisms choose the habitat based on the availability of basic requirements such as food, nutrients, space, etc. in the region. The absence of one or more of these factors makes them choose another habitat. Butterflies feed on nectar made by plants in their flowers. To make the butterflies stay in the landscape, flowering plants adapted to local conditions should be planted. The butterflies would feed on the nectar of these plants and would stay in the landscape.
Not enough ..................
It would require frequent rainfall. It cannot survive on dry land without constant water.