Answer:
True statements about transcription:
- Occurs in the nucleus
- Produces single-stranded mRNA using the antisense DNA strand as a template
- Precedes 5' capping and polyadenylation.
Explanation:
Transcription is the process by which a specific fragment of DNA (e.g., a gene) is used as template to synthesize a complementary RNA sequence, usually a messenger RNA (mRNA) molecule, which is then used to synthesize a protein in the ribosomes by a process called 'translation'. In eukaryotic cells, transcription occurs within the cell nucleus which contains the genetic material of the cell. Transcription factors are proteins that bind to DNA regulatory elements (e.g., promoter sequences) located at the 5′ end of the transcription initiation site and thus stimulate transcription. Both mRNA capping (5' cap) and polyadenylation are post-transcriptional modifications that serve to protect the nascent mRNA from enzymatic degradation and help in ribosome binding during translation.
Answer:
A, B, C
Explanation:
One is a channel, one is a carrier, the other is simple
The link where the action
potential of the nerve that meets muscle and causes it to contraction is where excitation-contraction coupling occurs. The T_tubules the
invaginate into the sarcolemma of the muscle cells are the ones that carry the excitation into the muscles. Its depolarization
causes the lateral sacs of the sarcoplasmic reticulum to release ca2+
ions. The ca2+ then bind into their site on troponin and causes the tropomyosin to shift and allow actin to expose
the binding site in which myosin head
will bind and form a cross bridge that is
important in the contraction of the muscle.
Answer:
The nucleus tells other parts of the cell what to do
Explanation: