Answer:
Negatively charged phosphate groups of two strands are aligned distantly from each other in a DNA double helix.
Explanation:
DNA double helix is formed when the complementary bases of two single DNA strands pair with each other. The formation of double-stranded structures places the negatively charged phosphate groups of two single DNA strands away from each other. This is because complementary base pairs are present between the sugar-phosphate backbones of two DNA strands of a double helix. The double-helical structure also concentrates the nitrogenous bases away from the surrounding watery medium. Altogether, these factors stabilize DNA dyad.
Answer:
B) Nitrogen-fixing bacteria and lightning
Explanation:
Nitrogen cycle is the natural process in which atmospheric nitrogen is converted into nitrite and nitrate with the help of bacteria.
Nitrogen cycle is directly dependent on nitrogen-fixing bacteria and lightning.
As bacteria are responsible for most of the chemical conversion in the nitrogen cycle such as nitrogen fixation (first step) is done by soil bacteria (Cyanobacteria) that form ammonia, which is toxic to plants; nitrification in which ammonia is converted into nitrites and nitrates with the help of Nitrobacter and denitrification bacteria involve Pseudomonas, and Achromobacter which convert nitrite and nitrate into nitrogen.
The lightning breaks nitrogen molecules and allow it to combine with oxygen in atmosphere which further dissolve in rain and form nitrates.
Hence, the nitrogen cycle is most directly dependent upon nitrogen-fixing bacteria and lightning and the correct option is B.
The heterozygous birds phenotype would therefore be black and white because both parent genes are dominant so they would be fully expressed,none would overpower the other(no dominant or recessive) this is known as Codominance and and example of this is with the blood types.
Answer:the answer is the second
Because cell wall made up of most cellulose while cell membrane the outer if the animal cell
Answer:
Common Kingfishers measure 17 – 19 centimetres in length, weigh between 34 – 46 grams and have a wingspan of 25 centimetres. Their beak is around 4 centimetres long and pointed. Kingfishers have short, orange coloured legs. Kingfishers are very brightly coloured. The colour of their wings is a blue/green colour and their upperparts, rump and tail are a bright blue colour. Their underparts are bright orange and they have a small, white bib underneath their beaks, on their throats.
Explanation: