The correct answer is a - silicon dioxide.
Diatoms are single celled algae. They have a silica - based cell wall called a frustule, which gives each diatom a particular shape.
Diatoms exist as separate single cells although some may be found in groups or colonies. The ones found in colonies create very pretty forms: leaf shaped, oval , star and even like a period.
Outer shells of diatoms are quite valuable. They are used in industry in the manufacture of toothpaste to give it grit.
Answer:
Diatoms have cell walls composed of silicon dioxide.
together with Earth
c.
from a portion of Earth
b.
separately from Earth
d.
from a leftover star
Answer: together with earth.
Answer:
In anaerobic respiration, one molecule of glucose is broken down into two molecules of ethanol (in yeast) or lactic acid (in muscle cells) with a net gain of two molecules of ATP (adenosine triphosphate).
Two molecules of carbon dioxide are released as the byproduct.
It helps in regenerating the NAD⁺ lost in the process of glycolysis.
The overall process is termed as fermentation.
Lactic acid fermentation is catalyzed by the enzyme lactate dehydrogenase and alcohol (ethanol) fermentation is a two-step process which is catalyzed by pyruvate decarboxylase and alcohol dehydrogenase.
B. phototropism.
C. gravitropism.
D. thigmotropism.
Answer:
The answer is D.
Explanation: