Blood moves very slowly through capillaries. As the blood moves through a capillary, nutrients, oxygen, and food leave the blood and enter the body cells. ... Capillaries are exchange vessels. Gases (oxygen and carbon dioxide), nutrients, and wastes pass in both directions across capillary walls.
Kingdom Monera was the oldest kingdom of living organisms. The organisms in the kingdom were simple, single celled and their cellular organelles were not covered by membranes. Prokaryotic bacteria were the first known Monerans. However, scientists think that Monerans were evolved into more complex eukaryotic organisms (Protists) with the passage of time.
But how did Monera (Prokaryotes) was evolved into Protista (Eukaryotes)?
Protista are eukaryotes, unicellular or simple multicellular organisms.Many theories were proposed for this evolution, but one that makes most sense was endosymbiotic theory. According to this, the first eukaryotic cells were evolved when two prokaryotic cells existed in an endo-symbiotic relationship. Larger prokaryotic cells engulfed smaller prokaryotic cells. The smaller cells got shelter and nutrients from larger cells and both co-existed in a mutualistic relationship. Both cells eventually evolved into organelles and got never aparted. This is how more complex organisms’ protists were evolved from simple monerans. It was a gradual process and took millions of years.
The earliest fungi were single-celled organisms that contain a flagella to move from one place to another. Recent studies indicate that fungi belong to a group of organisms which were evolved from protists over the course of time. These studies are based on the nucleotide sequence of fungi that matches to a large extent with old protists. It is estimates that fungi evolved 600 million years or even before.
Different organisms have different number of chromosomes
Answer: The question is not complete as options are not complete , the remain part are;
A. 3.7 years, photosynthetic bacteria.
B. 3.7 years cyanobacteria.
The correct option is
3.7 billion years old, cyanobacteria and stromatolite.
Explanation:
This is because cyanobacteria is the oldest fossil to exist and they have been in existence for about 3. 7 billion years. These cyanobacteria photosynthesized because they have thread like chlorophyll filament, they produce food through the process of photosynthesis which is needed for their survival and they release oxygen as bye product.
When a chlorophyll molecule absorbs light, the process of photosynthesis, or the transfer of light into sugar, begins. ... For each photon of light that enters and excites a chlorophyll molecule, one electron is released from the reaction center of Photosystem II. So it passes to the reaction center where energy excited pair of electrons, which "jump" to electron acceptor.
