Question

Eukaryotic and prokaryotic cells are two important kinds of cells encountered in our world. Do the following:

Explain how eukaryotic and prokaryotic cells differ.

Explain how the evolution of cells made cellular respiration possible, and

What environmental pressures necessitated cellular respiration?

Provide citations

Answer 1

Explain how eukaryotic and prokaryotic cells differ.

Answer: Difference between eukaryotic and prokaryotic cells

1. Eukaryotic Cell

a. Have true nucleus (nuclear membrane present)

b. Usually multicellular

c. Membrane bound cell organells are presents

d. Ribosomes are larger

2. Prokaryotic Cell

a. Have False nucleus (nuclear membrane absent)

b. Usually unicellular

c. Membrane bound cell organells are absent

d. Ribosomes are smaller

Explain how the evolution of cells made cellular respiration possible

Answer: The evolution of eukaryotic cell from prokaryotic cell made cellular respiration possible. As the eukaryotic cell are evolved from the prokaryotic cell and it is evidenced from the endosymbiotic theory, that attempts to explain the origins of eukaryotic cell organelles such as mitochondria in animals and fungi. Mitochondria are one of the many different types of organelles in the cells of all eukaryotes.In general, they are considered to have originated from proteobacteria (likely Rickettsiales) through endosymbiosis and this made cellular respiration possible.

What environmental pressures necessitated cellular respiration?

Answer:The aerobic bacterium which enters in to the cell cytoplasm of other cell by endosymbiosis provided abundant molecular food for its heterotrophic existence. They digested these molecules that manufactured enormous energy in the form of adenosine triphosphate (ATP), and so much so that extra ATP was available to the host cell's cytoplasm. This enormously benefited the anaerobic cell that then gained the ability to aerobically digest food. Eventually, the aerobic bacterium could no longer live independently from the cell, evolving into the mitochondrion organelle. Such aerobically obtained energy vastly exceeded that of anaerobic respiration, setting the stage for vastly accelerated evolution of eukaryotes.