Answer:
sieve-tube elements, companion cells
Explanation:
Sieve-tube elements and companion cells are responsible for the movement of photosynthes through a plant.
The sieve tube elements are shorter (almost organelle-free) living cells, placed end to end, forming the sieve tubes. Their transverse cell walls are called sieve plaques that make connections between cells and through openings called sieves establish the connection between the cytoplasm of adjacent cells. Each sieve is coated with calose (glucose polymer), which in winter can completely clog the vessel and then dissolve in spring. When infections occur or the vessel is parasitized, it can also be clogged with callose.
Companion cells are specialized parenchymal cells, which contain all the components that exist in living cells, including the nucleus, are the cells most closely linked to the sieved tube element. The Screened Tube Element and its companion cells are related in development, are derived from the same mother cell, and have several cytoplasmic connections to each other. Due to the many connections, the potential function of the companion cells is to release substances into the sieved tube element and, when the nucleus is absent, to include information molecules, proteins and ATP. When a screened element dies, its companion cells also die, which is a demonstration of this interdependence.
The correct answer is anticodon
Answer:
a. True
Explanation:
Ribosomes are ribonucleoprotein complexes composed of RNA and proteins, which have two main roles 1-decode the message of the messenger RNA (mRNA) molecule and the formation of peptide bonds in the protein. For this purpose, each triplet of nucleotide bases or 'codon' in the mRNA sequence is used to assemble specific amino acids in the nascent polypeptide chain. Although different, both prokaryotic ribosomes and eukaryotic ribosomes are composed of two subunits: one small subunit that decodes the mRNA into a specific amino acid chain, and one large subunit that forms the peptide bonds in the polypeptide chain. Each ribosomal subunit is in turn composed of ribosomal RNAs and proteins. These ribosomal RNAs act as scaffolds by combining with proteins that assemble into ribosomes (i.e., small and large ribosome subunits).
Answer:
Unequal heating of the earth
Explanation:
Warm air rises at the equator and moves towards the poles. At the poles, the cooler air sinks and moves back to toward the equator
Answer:
NAD+ act both as coenzyme as well as electron acceptor compound and get reduced to NADH by accepting electron.
Explanation:
NAD+ act as co enzyme of various biological catalyst such as malate dehydrogenase, isocitrate dehydrogenase etc.
NAD+ can act as co enzyme only in its oxidized form but not in its reduced form called NADH.
Many reaction needs NAD+ to occur such as conversion of glyceraldehyde 3 phosphate to 1,3 bisphosphoglycerate, malate to oxaloacetate.
That"s why NAD+/NADH ratio is kept very high because if this ratio bychance get low then it will hamper the normal redox potential of NAD+/NADH.As a result many biochemical reaction will not take place.
