1. How does DNA encode information? DNA is a double-stranded helix composed of a phosphate backbone and deoxyribose, and encodes information by the sequence of its nucleotide bases, which are composed of adenine, thiamine, guanine and cytosine. DNA undergoes transcription, which produces single-stranded mRNA, which uses uracil in place of thiamine. Next step is translation, in which the RNA becomes a protein, which then can act as structural units or enzymes. 2. How does DNA replicate itself? In order to replicate itself, DNA undergoes DNA replication, a process in which the DNA unwinds and splits in two. From that point on, new nucleotides are added to each of the original strands (A to T, C to G) until the result is two identical sequence copies of DNA. 3. How is DNA information used to synthesize polypeptides? A gene or protein is used to make polypeptides. In order to create this gene, transcription and translation must take place to create a protein from DNA. In transcription, DNA polymerase unwinds DNA and makes the …show more content…
Are all genes expressed in all cells? No they are not, even though all cells have the same genetic code. Certain genes are not expressed in cells and are turned "off". The different pattern of expressed genes in different cells allow the cells to perform specific activities needed for those cells to do for an organism. 5. How do the processes of meiosis and fertilization produce genetic variety? During the meiosis stage of crossing over, the maternal and paternal homologous chromosome segments are being exchanged. During independent assortment, different genes independently separate from one another. During random fertilization, no gamete has a greater chance than the other with fusing together in sperm and zygote fusion. These processes contribute to the production of genetic variety because of the many opportunities of unique combinations, unlike the process of mitosis, in which identical daughter cells are always the
Drosophila is a fly species that is used in genetics. Since Drosophila goes through life cycles extremely quickly, it is one of the best specimens to use in a multiple generation experiment. The purpose of this experiment is to follow the genetic phenotype of the offspring and determine the genotype, which will most likely predominately be the wild type phenotype with a few recessive traits. To conduct the experiment, we first cross the parents, wild type with sepia eyes and vestigial wings or black body with vestigial wings. The offspring from that cross is expected to be 100% wild type and the following cross between the F1 generation is expected to be 9:3:3:1.
fertility and type of offspring depends on which cell line gave rise to the ovaries or testes; varying degrees of intersex differences may result if one set of cells is genetically female and another genetically male. Tetragametic chimerism Tetragametic chimerism is a form of congenital chimerism. This condition occurs through the fertilisation of two separate ova by two sperm, followed by aggregation of the two at the blastocyst or zygote stages. This results in the development of an organism with intermingled cell lines.
rRNA forms a part of both subunits on a ribosome, in which proteins are assembled. tRNA take amino acids to the ribosome and matches them to the coded mRNA message. 1c. Infer: Why is it important for a single gene to be able to produce hundreds or thousands of
Part one is an enzyme called CAS-9, this is basically a pair of molecular scissors that can cut the two strands of DNA at a specific location in the genome so that bits of DNA can then be added or removed. The second part is a piece of RNA called guide RNA, this includes a small piece of pre-designed RNA sequence located within a longer RNA strand. The strand part binds to DNA and the pre-designed sequence ‘guides’ Cas9 to the right part of the genome. This makes sure that the Cas9 enzyme cuts at the right point in the genome. The guide RNA is designed to find and bind to a specific sequence in the DNA.
This apparently makes me feel astounded, as this kind of terminology is used to describe the fertilization process. Instead of using such fairy tale metaphors, real life, true and non-biased examples would have provided better
Cellular information passes from one generation to the next in the form of Dna through a process called meiosis. Cellular information is stored in Dna, which is wound tightly around proteins in a double helix to form chromatin strands, which in turn are wound tightly to form chromatids. A normal human has 92 chromatids. After dna replication occurs in the S phase of meiosis, these chromatids duplicate themselves to form sister chromatids that are held together by a centromere. This becomes a chromosome, which then travels through the process of meiosis.
The virus enters the cell, making it home. When inside its cytoplasm, the virus uncoats itself after which it then proceeds to release genetic material within it, along with nuclear proteins and enzymes. These materials along with the single stranded RNA it releases will now be used as a stencil for the new viral genomes. A genome of an organism is its entire DNA structure inclusive of all of its genes which contain the necessary information needed for the construction, development and maintenance of the organism. All of these help in its effective replication.
The chemical structure of everyone's DNA is the same. The only difference between people (or any animal) is the order of the base pairs. There are so many millions of base pairs in each person's DNA that every person has a different sequence. Using these sequences, every person could be identified solely by the sequence of their base DNA fingerprinting also called DNA Typing in genetics is the method of isolating and making images of sequences of DNA (deoxyribonucleic acid). The technique was developed in 1984 by the British geneticist Alec Jeffrey’s, after he noticed the existence of certain sequences of DNA (called mini satellites) that do not contribute to the function of a gene but are repeated within the gene and in other genes of a DNA sample.
- Where DNA can be found and the role does DNA play in heredity?-DNA is found in every cell within the nucleus (Eukaryotic cells) apart from blood cells. Chromosomes are made up of thin strands of (DNA). Each chromosome pair contains thousands of genes. The human genome is made up of about 3 billion chemical bases that are arranged in patterns similar to individual letters arranged into sentences. (Professor Stuart E. Ravnik Texas Tech University Health Sciences Center).
INTRODUCTION:- Several experiments have shown the presence of the genes on chromosomes inside the nucleus. These genes inside nucleus control the phenotypes of the organisms and are transmitted from one generation to next generation. This hereditary transmission is known as Mendelian Inheritance. The nuclear genes are inherited from male and female parents in equal proportions and contribute equally to the genetic constitution of the offspring.