Explanation:
Crossing over, or genetic recombination contributes to genetic variation and diversity.
In early Prophase I of meiosis, crossing over occurs. This is the exchange of segments of chromosome, between non-sister homologous or similar chromatids crossing over happens at chiasmata, the point where non-sister chromosomes are joined. The chromosome pairs form tetrads held together at chiasmata.
Further Explanation:
All the genetic information within the eukaryotic cell is stored within the nucleus as helical DNA. This DNA is tightly wound around histones as chromosomes. To produce daughter cells, the chromosomes (total number of chromosomes (2n)) are copied before the cell splits into two daughter cells. This process is known as mitosis, and occurs in cell division and growth processes. Two new nuclei are formed, along with identical cells. These are the same as the parent cell and the chromosome number (2n) is maintained. Conversely in meiosis, the number of chromosomes (2n) is halved through meiotic divisions, producing 4 (n) germ cells (sperm or eggs), each containing half the number of chromosomes as its parent cell.
During the process of prophase I one the nuclear envelope containing chromosomes has only partly broken down homologous chromosomes are joined together by proteins and a complex or pairing call synapsis- corresponding genes on chromatids are aligned precisely. The syanpsis allows for crossing over which is the exchange of segments of chromosome, between non-sister homologous or similar chromatids crossing over happens at chiasmata, the point where non-sister chromosomes are joined.
Crossing over contributes to genetic variation and diversity; novel gene combinations in gametes are formed, which are not present in parent chromosomes. Genetic diversity describes all the genetic characteristics or traits within a species.
Learn more about mitosis at brainly.com/question/4303192
#LearnWithBrainly
Answer:
One of water's important properties is that it is composed of polar molecules: the hydrogen and oxygen within water molecules (H2O) form polar covalent bonds.
Explanation:
Answer:
Whole spices will stay fresh for about four years, while ground spices run between three and four years
Explanation:
Answer:
c) allowing an organism to adjust to changes in environmental conditions
Explanation:
A stimulus can be defined as any change in the external or internal environment that produces a corresponding response in the organism. These responses enable the organism to maintain an internal equilibrium (homeostasis). Gene expression in prokaryotes, which are the simplest forms of life, is highly regulated by environmental stimuli. Some examples of stimuli known to regulate gene expression patterns in prokaryotic organisms are light, water, pressure, temperature, etc.
