Answer:
1. Double helix is the description of the structure of a DNA molecule. A DNA molecule consists of two strands that wind around each other like a twisted ladder. Each strand has a backbone made of alternating groups of sugar (deoxyribose) and phosphate groups.
2. The DNA double helix. The two sides are the sugar-phosphate backbones, composed of alternating phosphate groups and deoxyribose sugars. The nitrogenous bases face the center of the double helix.
3. A nucleotide is an organic molecule that is the building block of DNA and RNA. ... A nucleotide is made up of three parts: a phosphate group, a 5-carbon sugar, and a nitrogenous base. The four nitrogenous bases in DNA are adenine, cytosine, guanine, and thymine.
4. A nucleotide is made up of three parts: a phosphate group, a 5-carbon sugar, and a nitrogenous base. The four nitrogenous bases in DNA are adenine, cytosine, guanine, and thymine.
5. In genetics, the term junk DNA refers to regions of DNA that are non-coding. Some of this noncoding DNA is used to produce noncoding RNA components such as transfer RNA, regulatory RNA and ribosomal RNA
Hopes this helps.
The male
human has a sperm cell and the female has an egg cell. The cells from the male
and female that combine to form a zygote are called gametes. The human sperm
and egg cells each contain 23 chromosomes. . A combination of gametes forms a
zygote with 46 chromosomes. The type of cell division that produces gametes
with half the normal chromosome number is the meiosis. Meiosis is the type of
cell division used in sexual reproduction. It will occur in the testes and
ovaries.<span>Chromosomes get
shuffled when eggs and sperm are made. Though most adult cells contain two sets
of chromosomes, sperm and egg cells are different. These special cells have
just one chromosome from each pair. Which chromosome they get from each pair is
random, making each sperm or egg cell unique. There is also a bit of mixing
before the chromosomes are sorted into individual sperm or egg cells.
Chromosomes from each pair in a mother or father, respectively, make contact
and exchange pieces of DNA, creating hybrid chromosomes. </span>
Answer;
DNA replication is semi-conservative.
The meselson-stahl experiment supported the hypothesis that DNA replication is semi-conservative.
Explanation;
The Meselson-Stahl experiment was an experiment by Meselson and Stahl that proved that the semi-conservative model by Watson and Crick was correct.
DNA replication is semi-conservative in the sense that the new helices formed after replication contain, one new DNA strand and one old strand from the parent DNA molecule.
Answer:
The correct selection of answers to the question: Identify the pieces of evidence describing the features of DNA that Watson and Crick used to determine the structure of DNA, would be:
C: The two chains are parallel, both running in a 5´ to 3´ direction
D: A purine base forms hydrogen bonds to pair with a pyrimidine base located on the opposite DNA strand. Specifically, A pairs with T, and C pairs with G.
E: The sugar-phosphate backbones of each DNA helix run antiparallel to one another
F: The diameter of the DNA doube helix is 2 nm, with each purine-pyrimidine base pair spanning an equivalent distance between the two chains.
Explanation:
Although Watson´s and Crick´s research, and model of the DNA helix, became the breakthrough for science, as it visually presented the now known characteristics of DNA, this research was possible due to the way that these two researchers used previous information found by other scientist on the molecule, to finally build their model. All of the options that were selected were part of the research of several scientis, including Mendel, Rosalin Franklin, Linus Pauling, Maurice Wilkins, Oswald Avery and many others, who worked on different aspects of specimens and their specific characteristics, and which led them to discover that organisms possessed DNA, that this was the unit of information that directed all functions in living cells and how this DNA helix was chemically built to understand how it worked, and why it worked the way it did.
No our galaxy does not contain any planets outside our solar system
