I think it is d - as plants animals and insects etc all do this
Selectively permeable (or semi permeable) means where for example a membrane can choose what material can pass through while others cannot. They control the in and out of materials.
This is because the membrane has tiny spaces, where only smaller molecules can pass through, other larger ones cannot.
Answer:
a mucus or a gelatinous sheath
Explanation:
Most species of cyanobacteria are enclosed in a gelatinous sheath which is made up of proteins.
The answer i believe is d.
hope this helps!!!
If your findings disproves your hypothesis then your hypothesis is probably wrong.
