Explanation:
sexual reproduction is the process of fusion of male gamete and female gamete producing a genetically different offspring .Meiosis is a process where a single cell divides twice to produce four cells containing half the original amount of genetic information. meiosis leads to variation by forming new combination of alleles from maternal and parental chromosome
(choose which answers suits the question )
Explanation:
Meiosis leads to the formation of gametes which have half the number of chromosomes in the somatic body cells. This means two gametes should fuse together for a new individual to form. The two gametes coming from two different parents carry features from two individuals, and this is the first source of variation.
The process of independent assortment happens during metaphase I where the chromosomes from both parents align on the equator of the cell in an independent way, meaning some from each parent on one side, and the opposite on the other. This means the gamete formed has a mixture of chromosomes from the parent's parents, and this is the second source of variation.
Finally there is the crossing over which happens also in metaphase I where genetic material between the homologous chromosomes is exchanged. This means not the whole parental chromosome goes to one cell, but rather a mixture of both the paternal and the maternal in this one chromosome go to one cell, and an opposite mixture goes to the other. And this is the third source of variation.
Important to the story or to present, past, or future
Answer
Crater
Explanation
When there is a volcanic eruption, lava , gases, ash and rocks are released on to the surface as super hot mix. The material that has been pulled out of the earth surface form visible volcanic land forms which include caldera, craters, lava domes and lava plateaus.
Answer:
When the solutions (including inside and outside) were replaced by NaCl, the membrane potential changes from a negative value of -60 mV to a positive value of + 60 mV.
Explanation:
According to the Nernst equation the potential of the membrane for a two-compartment model of a cell for positive gradient of K⁺ ions is V = - 60 mVlogK'/K where K' = inside concentration of K⁺ ions and K = outside concentration of K⁺ ions. For a 10 fold excess of KCl in the inside compartment, K'/K = 10. So,
V = - 60 mVlogK'/K = - 60 mVlog10 = -60 mV.
For a negative gradient of Na ions is V = + 60 mVlogK'/K where K' = inside concentration of Na⁺ ions and K = outside concentration of Na⁺ ions. (Since the cell is selectively permeable to Na⁺ ions. So, Na ions to not flow out but in.)For a 10 fold excess of NaCl in the inside compartment, K'/K = 10. So,
V = + 60 mVlogK'/K = + 60 mVlog10 = +60 mV.
So, when the solutions (including inside and outside) were replaced by NaCl, the membrane potential changes from a negative value of -60 mV to a positive value of + 60 mV.