Answer:
The main function of the RB protein is to inhibit the transition from the G1 to S phase. Its activity depends on its phosphorylation state: if RB is not phosphorylated (active state), it is bound to the transcription factor E2F, preventing its translocation to the nucleus and the activation of genes necessary for DNA synthesis; and if it is phosphorylated, by cyclin-CDK complexes, E2F is released and cell proliferation occurs.
Explanation:
Retinoblastoma (Rb) was the first tumor suppressor described and, as we know today, mutations in its structure determine a large number of cancers. Structurally, we speak of a large and multifunctional protein; which is organized in different domains. The activity of this protein is regulated, mainly, by phosphorylation at multiple sites described over the years and is involved in control mechanisms of the cell cycle, apoptosis and senescence.
Answer:
Actin filaments return to their original positions (does not occur in muscle contraction, according to the sliding filament model).
Explanation:
Answer:
DNA replication is described as semi-conservative.
Explanation:
DNA replication is described as semi-conservative because each double helix formed comprises one strand from the helix from which it was copied and a new strand. That is, the replication of one helix results into two new copies of which each contains one of the original double stranded helix from which it was synthesized.
Gram staining
Gram-positive turns pink or red
Gram negative turns dark blue or purple
<span>A warm front is the boundary between a warm air mass and a cold air mass it is overtaking. So a cold front would be the opposite.
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