Cell division is the process by which a parent cell divides into two or more daughter cells.[1]Cell division usually occurs as part of a larger cell cycle. In eukaryotes, there are two distinct types of cell division: a vegetative division, whereby each daughter cell is genetically identical to the parent cell (mitosis),[2] and a reproductive cell division, whereby the number of chromosomes in the daughter cells is reduced by half to produce haploid gametes(meiosis). Meiosis results in four haploid daughter cells by undergoing one round of DNA replication followed by two divisions. Homologous chromosomes are separated in the first division, and sister chromatids are separated in the second division. Both of these cell division cycles are used in the process of sexual reproduction at some point in their life cycle. Both are believed to be present in the last eukaryotic common ancestor.
Prokaryotes (bacteria) undergo a vegetative cell division known as binary fission, where their genetic material is segregated equally into two daughter cells. All cell divisions, regardless of organism, are preceded by a single round of DNA replication.
For simple unicellular microorganisms such as the amoeba, one cell division is equivalent to reproduction – an entire new organism is created. On a larger scale, mitotic cell division can create progeny from multicellular organisms, such as plants that grow from cuttings. Mitotic cell division enables sexually reproducing organisms to develop from the one-celled zygote, which itself was produced by meiotic cell division from gametes. After growth, cell division by mitosis allows for continual construction and repair of the organism.[3] The human body experiences about 10 quadrillion cell divisions in a lifetime.[4]
The primary concern of cell division is the maintenance of the original cell's genome. Before division can occur, the genomic information that is stored in chromosomes must be replicated, and the duplicated genome must be separated cleanly between cells.[5] A great deal of cellular infrastructure is involved in keeping genomic information consistent between generations.
<span>The probability of an action potential being propagated from neuron to neuron is increased when the postsynaptic neuron's signal is in an excitatory state. During this state, the action potential of a presynaptic neuron increases the probability of transmission of a signal to the postsynaptic neuron.</span>
The man with blood type A might have one of two genotypes:
1. Iᵃ Iᵃ<span>
2. </span>Iᵃ i
In this case, Iᵃ is an allele for A group, and i is an allele for 0 group.
The ABO blood type is controlled by a single gene (the ABO gene) with three types of alleles (Iᵃ Iᵇ and i)
<span>According to a source the answer is B. They save energy and metabolites and help the organisms to respond to the environmental changes.
</span>A genotype is a set of genes in the human DNA responsible for different traits. It represents your complete identity that you will inherit from your parents and ancestors.
<span>On the other hand, a phenotype is how that trait expresses physically, a characteristic, a visible description of your physical features, including height, eye color, overall health, history of diseases, the ability to gain or lose weight fast, what type of food you like, what you enjoy and what you hate. </span>
Answer:
nitrogen can be changed into macromolecules like proteins and nucleic acids (DNA and RNA)
Explanation:
