Answer:
Option C
Explanation:
The cyanobacteria is the oldest life form that once existed on planet earth some 3.7 billion years ago. These cyanobacteria formed layered structures fossils which are called as stromatolites
Hence, stromatolites are the fossilized colonies of cyanobacteria.
A set of rocks in Greenland show the evidence of cyanobacteria as a living organism.
These stromatolites have layered structure of bio-chemical accretionary that are produced by trapping sedimentary grains through biofilms of microorganisms such as cyanobacteria.
Hence, option C is correct
Answer:
provides tensile strength and protection against mechanical and osmotic stress.
Answer:
Quartz has a hardness of 7.
Explanation:
On Moh’s Scale of Hardness, the quartz mineral takes place on the seventh hardest mineral. So the answer would be A-Equal to 7.
Answer:
Stomata - specialized cells that contract and expand to open or close pores for gas exchange. Stomata can adjust to temperature, staying closed when temperatures are hot and dry to prevent gas and water loss.
Explanation:
Stomata (singular stoma) are pores found in the epidermis of plant leaves. Stomata open and close in response to the change in structure of two guard cells either side of the pore opening. When the guard cells are turgid, the stomata open, when they are flaccid, they are closed.
This functions to permit gas exchange while preventing the loss of water, especially during hot, dry weather. The stomata can only open when the guard cells are turgid, pulling the stomata apart.