Answer:
C
Explanation:
Protozoa have been classified into three trophic categories: the photoautotrophs which harness the sun's radiant energy in the process of photosynthesis; the photoheterotrophs, which although phototrophic in energy requirements, are unable to use carbon dioxide for cell synthesis and must have organic carbon compounds
Answer:
Prokaryotic cells are much smaller than eukaryotic cells, have no nucleus, and lack organelles. All prokaryotic cells are encased by a cell wall. Many also have a capsule or slime layer made of polysaccharide. Prokaryotes often have appendages (protrusions) on their surface.
Answer:
Hydrogen
Explanation:
hydrogen couldn't form until the universe had cooled enough to allow their nuclei to capture electrons, about 380,000 years after the Big Bang, Within about 3 minutes after the Big Bang, conditions cooled enough for these protons and neutrons to form hydrogen nuclei.
