Humans are called heterotrophs
The Lock-and-key mechanism was first proposed by Emil Fischer which described as the enzymatic reactions whereby an enzyme with a single substrate binds temporarily to form a substrate complex.
The lock-and-key mechanism is usually associated with the complementary shapes of an enzyme with a single substrate, wherein the lock that is being referred to is the enzyme and the substrate is the key. One right sized substrate (key) fits into the active site (key hole) of the enzyme (lock).
The active site which is mentioned above is structurally complementary to the substrate. This is the temporary binding site on the enzymes. Just like a lock and key, the enzyme as the lock and the substrate as the key is said to fit together.
DNA
1. Found in nucleus
2. Sugar is deoxyribose
3. Bases are A, T, C, and G
RNA
1. Found in nucleus and cytoplasm
2. Sugar is ribose
3. Bases are A, U, C, and G
Since, it has a nervous system, blood vessels, and a long digestive tube is most likely a segmented worm.
<h3>What is a segmented worm?</h3>
Segmented worms have long tube-like bodies that are divided into segments.
They are the simplest organism with a true nervous system and blood contained in vessels.
They have a long digestive tube that runs down the length of the worm's inner body.
They can take in dissolved oxygen from the water through their skin.
Thus, a segmented worm has a nervous system, blood vessels, and a long digestive tube.
To learn more about a segmented worm click here:
brainly.com/question/970980
Cells, like bacteria and archaea, that do not have a nucleus in their cells have traditionally been called prokaryotes.
<h3>What are prokaryotic cells?</h3>
Prokaryotes are organisms whose cell (or cells) are characterized by the absence of a nucleus or any other membrane-bound organelles.
Prokaryotic cells are opposed to their eukaryotic counterparts that possess a membrane-bound nucleus that houses their genetic material (DNA).
Examples of prokaryotes are as follows:
Therefore, cells, like bacteria and archaea, that do not have a nucleus in their cells have traditionally been called prokaryotes.
Learn more about prokaryotes at: brainly.com/question/15329345
#SPJ1
