Explanation:
Transpiration, plant breathing, is when plants absorbs water from the roots using the xylem and phloem and takes them to the leaves where they exit as water vapour via the stomata (tiny openings). Through transpiration plants are able to cool themselves and produce their own food using the process of photosynthesis.
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:
Option A
Explanation:
Xeroderma pigmentosum arises as a result of the cell being unable to correct lesions induced by UV. This can be as a result of mutations in the enzymes which include XP A-E needed for correction of the lesions. Failure to correct these lesions leads to their accumulation and then damage to the cell.
The site
of calcium regulation is what differs from a mechanism of contraction in smooth
muscle from skeletal muscle. One of the
important functions of skeletal muscle contraction is production of heat and where
calcium seemingly acts to remove the blocking action of tropomyosin.