Answer:
Hey i think there is an error in ur question, u may recheck the so called word "metopus"
But here is the definition of Endosymbionts are organisms that form a symbiotic relationship with another cell or organism
When two protein chains combine to form an active protein, the structural level is quaternary.
<h3>What is a quaternary structure?</h3>
The quaternary and tertiary structure of a protein is the tridimensional shape of the protein, which involves protein domains.
The quaternary protein structure refers to the different arrangements generated by different protein subunits.
The primary structure of a protein involves its amino acid sequence, whereas the second structure involves protein chains.
Learn more about quaternary structure here:
brainly.com/question/5286438
2nd one is the right answer
Answer:
In photosynthesis it occurs on the thylakoid membranes.
Explanation:
It is where the light independent reaction occurs.