Ans.
Cell-to-cell communication allows signalling of essential substances between the plant cells, which are surrounded by cell walls. The molecules used by plants for long-distance signalling are known as hormones, such as auxin, ethylene, and gibberelin.
These hormones are secreted by one plant cell and received by another plant cell, where it exerts it affect. Thus, the correct answer to be fill in the blank is 'option A). hormones.'
The conditions depend on the density level of the snow.
Another reason is the imperfect data gathering especially if initial results are only gathered.
The third reason is that computer models still find it difficult to see small scale phenomena.
Answer:
A. to conserve soil nutrients
Explanation:
Crop rotation helps to maintain soil structure and nutrient levels. If you don't rotate crops, the soil in that field will inevitably begin to lose the nutrients plants need to grow.
Answer:
When the seed germinates, the two cotyledons emerge from the soil to form the seed leaves. The seed leaves nourish the plant until it can form its true leaves. (Not all dicots' seed leaves emerge during germination; for example, peas are dicots, but the pea cotyledons remain underground.)
Explanation:
Answer:
a) DNA fragments associated with histone proteins are all multiple in length (i.e., 260 bp, 520 bp, 780 bp, etc), thereby suggesting the presence of a pattern of organization in the chromatin
b) it suggests that each unit of organization (ie, each nucleosome) consists of 260 bp associated with chromatin proteins
Explanation:
The nucleosome is considered as the basic unit of chromatin. A nucleosome consists of approximately two turns of DNA wrapped around a core of eight histone proteins (i.e., a histone octamer). The histone octamer consists of two copies of each of the histones H2A, H2B, H3, and H4. Moreover, the nucleosomes are connected together by linker DNA sequences which vary between 10 and 100 bp in length.