The correct answer is d. 3.5 billion years.
Prokaryotes were the first forms of life on Earth long before simple multicellular life appeared because of their ability to withstand extreme conditions. It is believed that the first living forms were bacteria combined with archaea in the microbial mat (multi-layered sheet).
Answer:
The correct answer is option c. "frameshift mutations".
Explanation:
The reading frame of a gene is based on base-pair triplets, starting from the start codon until the ribosome encounters with the end codon. Base-pair additions and deletions are collectively referred to as frameshift mutations because they alter the reading frame of the gene. Base-pair additions and deletions break down the original sequence of the gene triplets, which alters the open reading frame and usually results in the production of non active proteins.
Answer:
The protist that changes shape constantly and flows around its food to engulf it <u>Amoeba </u>
<u>amoeba</u><u> </u><u>is </u><u>the </u><u>answer </u>
<u>maybe </u><u>I </u><u>think</u><u> </u><u>this </u><u>might </u><u>be </u><u>the </u><u>correct</u><u> </u><u>answer</u>
Answer:
The three muscle layers in the stomach's mascularis externa.
Explanation:
The stomach has four layers in their wall; The mucosa which is the inner lining of the stomach that secretes hydrochloric acid. The submucosa made of connective tissues, nerve fibres and blood vessels. The mascularis externa, made of 3 muscle layers responsible for contraction and parastalsis. The outer fibrous membrane or layer called serose.
The muscularis externa in the stomach is unique in that it has three muscle layers compared to the rest of the gastrointestinal tract. This is because the stomach has to work extra hard in mechanically breaking down chunks of food into smaller pieces during digestion.
