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Daryl Collins

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What is a gene
GeneThe central dogma of genetics was that one gene coded for one enzyme this was later altered to one gene coded for one polypeptide.

As we learn more about genetics, this begins to look like an overly simplistic view of the concept of gene. The exact definition of the term gene is in debate at the moment, as is the use of the term at all in the future. The discovery of very short RNA's (miRNA, siRNA's) which influence gene expression (without translation into peptides) are part of this debate.

Definitions

A gene is a unit of heredity in a living organism. It is normally a stretch of DNA that codes

for a type of protein or for an RNA chain that has a function in the organism. All proteins and functional RNA chains are specified by genes. All living things depend on genes. Genes hold the information to build and maintain an organism's cells and pass genetic traits to offspring. A gene is a unit of in a living organism. It is normally a stretch of DNA that codes for a type of protein or for an RNA chain that has a function in the organism.

Genes hold the information to build and maintain an organism's cells and pass genetic traits to offspring. A gene is a part of a DNA molecule that codes for a particular trait of an organism. It provides instructions on how to make a polypeptide. For example, one gene may code for the production of tyrosinase, which is an enzyme (protein) used in the synthesis of melanin (a pigment responsible for dark colors in skin and fur).

By the traditional definition, a gene is 'transcribed' into mRNA which is then 'translated' into a protein, which will produce the desired effect in an organism's cell. Some genes may contain instructions for the production of RNA that is not translated into a protein, such as tRNA, rRNA, miRNA and siRNA.

Conclusion

In essence, a gene is a section of a DNA molecule that has a unique and specific biological function.

What is a chromosome

A chromosome is a threadlike strand of DNA in the cell nucleus that carries the genes in a linear order. It is also known as tightly wound DNA. It is a structure that DNA wraps around.

MORE INFORMATION:

A chromosome is an organized structure of DNA and protein that is found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.

Chromosomes vary widely between different organisms. The DNA molecule may be circular or linear, and can be composed of 10,000 to 1,000,000,000 nucleotides in a long chain.

Cells may contain more than one type of chromosome; for example, mitochondria in most eukaryotes and chloroplasts in plants have their own small chromosomes.

Chromosomes are the essential unit for cellular division and must be replicated, divided, and passed successfully to their daughter cells so as to ensure the genetic diversity and survival of their progeny.

Chromosomal recombination plays a vital role in genetic diversity. If these structures are manipulated incorrectly, through processes known as chromosomal instability and translocation, the cell may undergo mitotic catastrophe and die, or it may aberrantly evade apoptosis leading to the progression of cancer.

In practice "chromosome" is a rather loosely defined term. In prokaryotes and viruses, the term genophore is more appropriate when no chromatin is present. However, a large body of work uses the term chromosome regardless of chromatin content. The simplest genophores are found in viruses: these DNA or RNA molecules are short linear or circular genophores that often lack structural proteins.

Chromosomal DNA encodes most or all of an organism's genetic information; some species also contain plasmids or other extrachromosomal genetic elements.
Structure in nucleus made of DNA and protein. Sections of a chromosomes are genes.
structure in a cell's nucleuse thaat contians genetic material
A chromeosome is organized structure of DNA and protein that is found in cells.
coiled strands of genetic material
coiled strands of genetic material

What happens during telophase

During telophase the cell membrane gets "pinched" and the orgenelles and DNA are split. following telophase is cytokinesis when the cell membrane is sealed off and the mother cell becomes two sister cells.

The final stage of meiosis or mitosis, in which the separated chromosomes reach the opposite poles of the dividing cell and the nuclei of the daughter cells form around the two sets of chromosomes.

This answer contributed by The Scientific Theory Academy of Science (STAOS)

In telophase nuclear membrane is begin to reform at both ends of the cell and spindle fibers disappear. chromosomes uncoil and return to chromatin form in preparation for Interphase. Cytokinesis coincides with this stage of mitosis.

All of this is true but a much easier answer to this question is that telophase is when a new nucleus forms around each copy of dna.

When is cytokinesis complete

It is complete when two daughter cells are produced. Cytokinesis is the process in which the cytoplasm of a single cell divides to form two daughter cells.

What is the role of microfilaments in cell division

They pull the cell membrane in.

They Split The Cell During Cytokinesis.

Which phase occurs directly after G1

S Phase - period of DNA replication - 10% shorter than G1.
After G1 phase S phase occurs.

Genetic disorders can result when chromatids fail to separate properly. During with phase is this problem most likely to occur

Anaphase

A mitosis inhibitor is a medication that is designed to prevent mitosis in certain cells why would these be helpful in the treatment of tumors

it would prevent tumor cells from reproducing.

How are meiosis and mitosis different

mitosis only has to do with celluar reproduction

meiosis has to do with sex cells reproducing
Mitosis creates new cells that are used for development, repair, asexual reproduction and growth. Meiosis creates cells in order for organisms to reproduce sexually.

Why aren't all organisms made of just one cell

Cell's divide, so there is always more cells.

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