<span>(According to Reference)
Whereas an onion epidermal cell has a cell wall, a human cheek cell does not. Instead, a semi-permeable membrane surrounds the cytoplasm of the cheek cell. While there are chloroplasts present in onion cells, they are absent in cheek cells. </span>
Answer:
1. D (In population genetics, gene flow is the transfer of genetic material from one population to another.)
2. C (Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation. It can also cause initially rare alleles to become much more frequent and even fixed. When there are few copies of an allele, the effect of genetic drift is larger, and when there are many copies the effect is smaller.).
3. A and also E (Individuals with inherited characteristics that allow them to best compete for limited resources will survive and have more offspring than those individuals with variations that are less able to compete. Because characteristics are inherited, these traits will be better represented in the next generation.)
4. D (Gene flow can increase fitness but if it happens in another environment, it decreases the adaptability. If alleles are advantageous, the offsprings' inheritance increases.
5. B (Mutations are the main source of alleles)
Answer:
major event of anaphase is the sister chromatids moving to opposite poles of cells due to action of the condensing spindle fibres.
Explanation:
the chromatids only start separating when the pressure is sufficient to split the centromere.
Probably d but definitely not A though..
Answer:
Please find the difference below and their respective examples
Explanation:
Previously existing organisms leave behind evidences of their existence in form of remains that has been collected and mineralized called FOSSILS. However, the fossils of an organism (plant or animal) can either be a trace fossil or an original remain/body fossil. The difference between the two are as follows:
- An original remain is the fossilized body or body part of an organism that once existed. For example, bones, shells and fossilized leaf are examples of original remains.
- On the other hand, trace fossils refers to any form of evidence, apart from the organism's body, that suggests the presence of that organism in that particular place at a particular time. Trace fossils are said to be illustrate presence of life but indirectly (via their activities). Examples of trace fossils are burrows, tracks, marks etc.
