Answer:
The cryosphere is the portion of the Earth's surface where water is in solid form. It thus includes sea ice, lake ice and river-ice, snow cover, glaciers, ice caps and ice sheets, and frozen ground. The snow cover has the largest extent, with a maximum area of more than 45 106 km2 (Table 1.1). Because of the present distribution of continents, land surfaces at high latitudes are much larger in the Northern Hemisphere than in the Southern Hemisphere. As a consequence, the large majority of the snow cover is located in the Northern Hemisphere (Figs. 1.15 and 1.16). The same is true for the freshwater ice that forms on rivers and lakes in winter. Both the snow cover and freshwater ice have a very strong seasonal cycle, as they nearly disappear in summer in both hemispheres (Table 1.1).
Explanation:
Answer:
The cell theory was given by Schwann and Schleiden. The fact that cells can be observed in plants, animals, fungi, protists, bacteria and archea comes from one of the postulates of cell theory- All living organisms are composed of one or more cells.
Explanation:
The cell theory initially contained three postulates:
- The cell is the basic unit of organization in all organisms.
- All living organisms contain one or more than one cell.
- All cells arise from cells which are already in existence.
The discovery of cell was made by Robert Hooke. Later after further observations, more points were added to the cell theory like
- The genetic component of the cell is DNA and is transferred within cells.
- The <em>chemical composition</em> of all the cells is similar.
- A flow of <em>energy</em> occurs within the cells.
According to this initial single gene autosomal cross, Mendel would have observed that the resulting offspring in the F1 or first filial generation are Tall. This is because, of the allele relationship that he observed, which is simple complete dominance.
The dominant or preferred allele or nucleotide sequence is used for the production of the protein, to allow for the appropriate colour.
Genotype would all be heterozygous Tt.
Answer:
Differentiation of heterochromatin and euchromatin decreases