1)Chargaff's rules state that DNA from any cell of any organisms should have a 1:1 ratio of pyrimidine and purine bases and, more specifically, that the amount of guanine should be equal to cytosine and the amount of adenine should be equal to thymine. This pattern is found in both strands of the DNA.
2)DNA structure
DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The order of these bases is what determines DNA's instructions, or genetic code.
3)A nucleotide consists of three things: A nitrogenous base, which can be either adenine, guanine, cytosine, or thymine (in the case of RNA, thymine is replaced by uracil). A five-carbon sugar, called deoxyribose because it is lacking an oxygen group on one of its carbons. One or more phosphate groups.
4)DNA replication is said to be semi-conservative because of this process of replication, where the resulting double helix is composed of both an old strand and a new strand. ... Semiconservative replication would produce two copies that each contained one of the original strands and one new strand.
5)The diagram has show in above.
6)complementary base pairing is necessary because the double helix shape would not be the same if not. Doubles would only pair with doubles and the singles to singles.
<u>HOPE</u><u> </u><u>THIS</u><u> </u><u>HELPS</u><u> </u><u>YOU</u><u>.</u>
Answer:
<u>D) the nucleic acid (either DNA or RNA)</u>
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Explanation:
Phages, or bacteriophages are viruses that infect bacteria.They have varying shapes, and sizes, and may contain one of two kinds of nucleic acid; these are RNA and DNA.
The nucleic acids are made up of nucleotides. These are genetic storage biomolecules made up of the monomers ribonucleic acid (RNA) deoxyribonucleic acid (DNA).
Answer:
When a muscle cell contracts, the myosin heads each produce a single power stroke.
Explanation:
In rest, attraction strengths between myosin and actin filaments are inhibited by the tropomyosin. When the muscle fiber membrane depolarizes, the action potential caused by this depolarization enters the t-tubules depolarizing the inner portion of the muscle fiber. This activates calcium channels in the T tubules membrane and releases calcium into the sarcolemma. At this point, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. When calcium binds to the troponin C, the troponin T alters the tropomyosin by moving it and then unblocks the binding sites. Myosin heads bind to the uncovered actin-binding sites forming cross-bridges, and while doing it ATP is transformed into ADP and inorganic phosphate which is liberated. Myofilaments slide impulsed by chemical energy collected in myosin heads, <u>producing a power stroke</u>. The power stroke initiates when the myosin cross-bridge binds to actin. As they slide, ADP molecules are released. A new ATP links to myosin heads and breaks the bindings to the actin filament. Then ATP splits into ADP and phosphate, and the energy produced is accumulated in the myosin heads, which starts a new binding cycle to actin. Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
They allowed scientists to study heredity and further develop it