Answer:
a) Teeth arose from the rough scales of ancestral sharks.
b) Skeletal developments leading to the amphibian movement onto land probably evolved from lobe-finned fishes.
d) The anterior gill arch formed the basis for the evolution of the vertebrate jaw.
Explanation:
The animals we know today have physical characteristics that are evolutionary adaptations of characteristics of their ancestors, which have undergone a series of evolutions and modifications over the years giving rise to new species that have resulted in the species we know today. This process of evolutions and adaptations also happened with the ancestral species of fish, which allowed that today, they had characteristics such as teeth and jaws. Many of these evolutions occurred even in different species, such as the evolution that allowed the amphibians to have a skeleton, which evolved from the spine fins of fish.
Answer:
A plant cell
Explanation:
In the given question, a stage of a cell has been described during cell division.
The characteristic of this cell division are:
1. Nuclei are formed at opposite poles- shows that it is the stage of cell division
2. The formation of cell plate- the cell plate is formed in the middle of the cell which indicates that the cell is a plant cell.This cell is a plant cell as the cell plate is formed only in the plant cells and not in the animal cell in which the contractile rings are formed.
Thus, A plant cell is correct.
A i think, i mean you get both
D- During interphase, when the cell is not dividing, chromatin is less tightly packed compared to our chromosomes, which allows transcription to occur.
Answer: There's no way one species can become another through depuranization, which is a random change.
Explanation:
In cells, environmental (chemical or physical) and metabolic factors can cause DNA damage, which is the molecule that stores genetic material. In these cases, the damage done to the DNA is repaired.
<u>Many of these lesions cause a permanent structural damage to the DNA, which can alter the ability to be transcribed, or can cause mutated genes to be transcribed resulting in another protein.</u> Particularly, depurination is the hydrolytically cleavage of the β-N-glycosidic bond between the purines (adenosine or guanosine) and the carbon of the sugar group found in the DNA. This mutation results in the loss of the purine base and leads to the formation of apurinic site and results and severely disrupts the DNA structure. The most important causes of depurination is the presence of endogenous metabolites inside the cell as a result of various chemical reactions and due to the presence of mutagenic compounds. However, these apurinic sites <u>are usually repaired by portions of the base excision repair (BER) pathway</u>.
There's no way one species can become another through depuranization, which is a random change. Because it is highly unlikely that 5000 mutations are able to accumulate every day without being repaired, and that they are just the right mutations to have the same characteristics as a chimpanzee. <u>If the depurinations are not repaired, the cell will most likely either die or become cancerous.</u>
