In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. This process occurs in all living organisms and is the basis for biological inheritance. DNA is made up of a double helix of two complementary strands. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, a process referred to as semiconservative replication. Cellular proofreading and error-checking mechanisms ensure near perfect fidelity for DNA replication.[1][2]
In a cell, DNA replication begins at specific locations, or origins of replication, in the genome.[3] Unwinding of DNA at the origin and synthesis of new strands results in replication forks growing bi-directionally from the origin. A number of proteins are associated with the replication fork to help in the initiation and continuation of DNA synthesis. Most prominently, DNA polymerasesynthesizes the new strands by adding nucleotides that complement each (template) strand. DNA replication occurs during the S-stage of interphase.
DNA replication can also be performed in vitro (artificially, outside a cell). DNA polymerases isolated from cells and artificial DNA primers can be used to initiate DNA synthesis at known sequences in a template DNA molecule. The polymerase chain reaction (PCR), a common laboratory technique, cyclically applies such artificial synthesis to amplify a specific target DNA fragment from a pool of DNA.
Answer:
Many amino acids in an enzyme molecule carry a charge . Within the enzyme molecule, positively and negatively charged amino acids will attract. This contributes to the folding of the enzyme molecule, its shape, and the shape of the active site. Changing the pH will affect the charges on the amino acid molecules
Answer:
The options:
A. incomplete digestive tract
B. gastrovascular cavity
C. complete digestive tract
D. complete digestive tract and a gastrovascular cavity
E. incomplete digestive tract and a gastrovascular cavity
The CORRECT ANSWER IS E.
E. incomplete digestive tract and a gastrovascular cavity
Explanation:
Phylum Cnidaria; Cnidarians are diploblastic with two embryonic germ layers -the ectoderm and the endoderm) with well structured tissue, performs extracellular digestion, and use cnidocytes for defence and to catch prey.
Cnidarians have two unique morphological body plans which are referred to as polyp, its sessile in adults, and medusa are mobile; some species has both body structures in their lifecycle.
It undergo extracellular digestion, where enzymes dissolve the food substances as its cells lining the gastrovascular cavity take in the nutrients.
Cnidarians are known to have a body arrangement of incomplete digestive system with just one opening; the gastrovascular cavity that functions as both a mouth and an anus.
The cnidarians undergo extracellular digestion, the food is moved to the gastrovascular cavity, enzymes are present in the cavity, with the cells lining the cavity taken in nutrients. The gastrovascular cavity possess a singular opening that acts as a mouth and an anus; this is referred to as an incomplete digestive system.
The parallels of latitude are of unequal length, whereas the meridians of longitude are of equal length.
<span>M (mitosis) phase is itself composed of two tightly coupled processes: mitosis, in which the cell's chromosomes are divided between the two daughter cells, and cytokinesis, in which the cell's cytoplasm divides in half forming distinct cells.</span>