Answer: Tightly wound chromosomes, composed of DNA, must unwind before replication. Cell replication splits a cell into two parts, both of which become new, fully functioning cells. Before this can happen, however, cells require a full complement of DNA for each of the new daughter cells that will form as a result of the split. Because of this, DNA makes a copy of itself in a process known as replication during interphase, a stage that occurs before cells divide.
Cell Phases: Mitosis is the process by which parent cells each divide into two identical daughter cells. However, this majority of the cell's time is spent in interphase, during which it performs normal metabolic functions necessary for the organism, such as manufacturing protein. DNA occurs during the S phase of interphase, sandwiched between the G1 and G2 phases. The cell uses checkpoint signals to ensure at the end of G1 that it is big enough to replicate and at the end of G2 to determine whether or not DNA replication has succeeded. If so, the cell can undergo mitosis, at which point DNA winds up tightly for easy transport during the process.
DNA Replication: Replication begins with DNA unwinding and unzipping, its two strands coming apart. While only one side is the “correct” code, containing the actual genetic information used to build the organism’s proteins, both can be the base for a new strand of complete DNA. The enzyme DNA polymerase matches up each base with the correlating base: adenine with thymine and guanine with cytosine. When each pre-existing base has been matched to a nucleotide, which also contains the sugar and phosphate of the DNA’s backbone, the strand is complete.
<span>The papillary region</span> is the structure that house Meissner's corpuscles, free nerve endings and capillary loops.
<span>This region is the superficial portion of the dermis, about 1/5 of the dermis. The papillary region consists of areolar connective tissue with thin collagen and fine elastic fibers.</span>
Answer: (idk if i chose more than 1)
I believe its the Last option (optional A)
Explanation:
it gives structures for reproduction, immune system, hormones, and protection of cells
Water is an important transport and reaction medium
hope this helps :)
Answer:
Chloroplast
its function is to create chemical energy using light energy
Explanation:
Photosynthesis occurs in chloroplasts which can be compared to mitochondria because they both produce energy for the organism. The Chloroplast contains within it a pigment, chlorophyll which captures the sun's energy and turns into energy which is used to create other parts of photosynthesis. Chloroplasts capture light energy from the sun to produce the free energy stored in ATP and NADPH through a process called photosynthesis. Chloroplasts are one of the many organelles found in the body, and are generally considered to have originated as endosymbiotic cyanobacteria. In this aspect, they are similar to mitochondria but are found only in plants and protist.
