The cytoskeleton provides energy to cilia
Explanation:
The motion of hair-like structures or axonemes called cilia or flagella are done through sliding movements of one another. This motion needs energy and motor protein molecules called dynein.
Dynein is a cytoskeletal motor protein present in the cytoskeleton and moves in the microtubules and converts the chemical energy in the ATP to mechanical energy to power the sliding and bending movements of cilia.
Apart from facilitating movement, cytoskeleton also contains other proteins which helps it to provide shape and support.
Flowering plant. Hope this helps
Answer:
- New seedlings: histone acetylation
- After cold exposure: histone methylation
Explanation:
Vernalization is an adaptive mechanism whose objective is to ensure that flowering occurs only after winter (i.e., after cold conditions). In certain plants, this process (vernalization) suppresses the expression of genes that encode repressors of flowering. In <em>Arabidopsis</em>, vernalization is associated with histone modifications at <em>FLC</em> chromatin. The <em>FLOWERING LOCUS C </em>(<em>FLC</em>) is a MADS-box gene that acts as a repressor of flowering in <em>Arabidopsis</em>. Epigenetic modifications control the expression of the <em>FLC</em> gene. The <em>FLC</em> gene is expressed at low temperatures due to histone acetylation at <em>FLC</em> chromatin, and thereby the expression of <em>FLC</em> mRNA transcripts ensures that the <em>Arabidopsis</em> plant cannot flower. Subsequently, as the <em>Arabidopsis</em> plant is exposed to cold, <em>FLC</em> is repressed by the accumulation of trimethylation on lysine 27 of histone 3 (H3K27me3), thereby allowing it to flower when temperatures become warmer.
The net result of these two closely linked pathways is the oxidation of nutrients to produce usable chemical energy in the form of ATP. In eukaryotic cells, the citric acid cycle occurs in the matrix of the mitochondrion.
