The correct answer is A. They produce food by photosynthesis.
Since leaves are the ones that photosynthesize food, here the stems have to do it because there are no leaves.
Yes. True vertebrates have a true head that develops from a neural crest of cells and hard structures surrounding the notochord.
The neural crest, which forms early in the development process in vertebrate embryos, is a fold on the neural plate where the neural and epidermal ectoderms converge. As an embryo grows, the neural crest produces neural crest cells (NCCs), which can differentiate into a variety of different cell types and contribute to tissues and organs.
The notochord is a temporary structure that plays a crucial role in higher animals. It secretes substances that communicate with all neighbouring tissues, telling them where they are and what will happen to them.
Therefore, True vertebrates have a true head that develops from a neural crest of cells and hard structures surrounding the notochord.
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The posttranslational alterations of proteins may include the addition of polysaccharides to proteins (Option 4).
<h3>What are posttranslational alterations of proteins?</h3>
The posttranslational alterations of proteins are different modifications in the protein sequences in order to activate their functions and or suppress them.
One of the most common posttranslational alterations of proteins is phosphorylation, which occurs at specific amino acid residues and it is able to activate or deactivate proteins in order to change the signaling pathway associated with their functions. Polysaccharides can also be added to proteins in order to change their functional states.
Therefore, with this data, we can see that the posttranslational alterations of proteins are able to modify the functional properties of a protein and polysaccharide addition in one of these types of modifications that both structural proteins and enzymes suffer to activate an or deactivate them.
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They can be observed in a microscope because both of them are very small to see. Mostly, they contain genetic material. Viruses need a host to keep it spreading or etc.
Answer: it's because they need to provide a lot of energy.
Explanation: fat cells have many mitochondria because they store a lot of energy. Muscle cells have many mitochondria, which allows them to respond quickly to the need for doing work.
