Answer:
All of the above
Explanation:
Calcium is very good for strong bones and also hair and fingernails.
A
B
AB
O
unless you're asking for specifics, like O+ and such, but I think you just wanted the main four, so there you go. hope this helps, but I may be wrong ^^
Answer:
transcription initiation
Explanation:
Transcription is a process by which genetic information from DNA is used to synthesize an RNA molecule, usually, a messenger RNA (mRNA), which is subsequently utilized to synthesize a protein by a process called translation. Transcription in prokaryotes has three steps:
1-Initiation: the RNA polymerase is a multisubunit enzyme (holoenzyme) composed of two α, one β, one β’ and one ω and σ subunits (α2ββ’ωσ). This holoenzyme binds to the promoter region of the template DNA strand.
2-Elongation. The sigma σ factor of the holoenzyme is released and the complex and the core enzyme (α2 ββω) moves along the template strand, thereby producing an mRNA sequence
3-Termination. This step can be Rho-dependent, where a protein named "Rho" recognizes the termination site and stop transcription, and Rho-independent (transcription continues until the termination sequence is reached).
In consequence, Rifamycin is likely to block the initiation of transcription because the core RNA enzyme needs to bind the sigma factor (σ) for initiation of transcription in bacteria.
- Xylem contains tracheids, vessels, xylem parenchyma and xylem fibre.
- Tracheids: They are elongated, tubular dead cells with tapering end walls.
- Vessels: These are also known as trachea. They are elongated, tubular dead cells. They are joined to each other by end to end forming a continuous pipe. The cells are thick and lignified.
- Xylem parenchyma: They are also called wood parenchyma. This is the only living tissue of xylem.
- Xylem fibre: They are dead cells with thick walled fibre.
- Phloem consists of sieve tubes, companion cells, phloem parenchyma and phloem fibres.
- Sieve tubes: These are elongated, tubular living cells arranged in a row, with their perforated end walls forming a sieve. They are non-nucleated. Their protoplasm are inter-connected through sieve plates. They possess vacuoles.
- Companion cell: They are elongated, lens-shaped cells containing dense cytoplasm and prominent nuclei. These cells maintain connection with sieve cells through pits.
- Phloem parenchyma: They are living thin walled parenchyma cells.
- Phloem fibre: They are also known as bast fibre. They are elongated fibre like sclerenchymatous dead cells with thick walls containing pits and interlocked ends. Phloem fibre are the only dead cells in phloem.
Hope you could get an idea from here.
Doubt clarification - use comment section.
The answer is <span>Special RNA polymerase, peptidoglycan in cell walls, ester-linked fatty acids.
Bacterial cell wall consists of peptidoglycans, not of cellulose or chitin. They also have ester-linked fatty acids, like eukaryotes. Ether-linked fatty acids are characteristics of Archaea. Also, bacteria have special RNA polymerase, unlike Eukaryotes that have three different type of RNA polymerase.</span>
