The right answer is A.
Plant species are particular in their ability to produce oxygen and carbohydrates through photosynthesis. The plant, just like the animals also needs to breathe so that these cells survive, so it is forced to take some of the oxygen and carbohydrate produced by photosynthesis to operate these cells through cellular respiration.
<span>Similarities and differences between intramembranous and endochondral ossification<span>
Ossification is the process of bone formation. Intramembranous and endochondral ossification are the two main processes of bone formation that occur during fetal development.
</span>Similarities between intramembranous and endochondral ossification<span>; they turn cartilage into bones during bone formation and they both involve bone cells such as calcium, vascular supply and osteoblasts.
</span>Differences between intramembranous and endochondral ossification<span>; In intramembranous ossification, an intermediate cartilage is not involved, rather the bone tissue is directly laid on a primitive connective tissue called mesenchyma while in endochondral ossification, cartilage is used as a precursor for bone formation. Also, in cases of fractures, the healing process by plaster of Paris occurs through endochondral ossification while fractures which are treated by open reduction and internal fixation are healed by intramembranous ossification.
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Answer:
(a) crossing over: Meiosis I, Recombination
(b) chromatids separate at their centromeres and migrate to opposite poles: Meiosis II, Anaphase II
(c) chromosomes become aligned in pairs at the equator: Meiosis II, Metaphase II
Explanation:
Homologous recombination is a type of genetic recombination that occurs during meiosis (formation of ovum and sperm cells). The paired chromosomes of the male and female parents are aligned so that similar DNA sequences intersect. This crossing over produces an exchange of genetic material, which is an important cause of the genetic variability observed in the offspring.
Meiosis II: Anaphase II. The centromeres separate and the daughter chromatids - now individual chromosomes - move to the opposite poles of the cell. The centromeres separate, and the two chromatids of each chromosome move toward the opposite poles in the spindle.
Meiosis II: Metaphase II. Chromosomes are accommodated in the equatorial plate of metaphase, similar to what happens in mitosis. They are attached to the already fully formed meiotic spindle. Each chromosome is aligned in the equatorial plate of the metaphase, as it happens in mitosis.
