Answer:
Once the oxygen diffuses across the alveoli, it enters the bloodstream and is transported to the tissues where it is unloaded, and carbon dioxide diffuses out of the blood and into the alveoli to be expelled from the body. Although gas exchange is a continuous process, the oxygen and carbon dioxide are transported by different mechanisms.
Transport of Oxygen in the Blood
Although oxygen dissolves in blood, only a small amount of oxygen is transported this way. Only 1.5 percent of oxygen in the blood is dissolved directly into the blood itself. Most oxygen—98.5 percent—is bound to a protein called hemoglobin and carried to the tissues.
Hemoglobin
Hemoglobin, or Hb, is a protein molecule found in red blood cells (erythrocytes) made of four subunits: two alpha subunits and two beta subunits (Figure 20.19). Each subunit surrounds a central heme group that contains iron and binds one oxygen molecule, allowing each hemoglobin molecule to bind four oxygen molecules. Molecules with more oxygen bound to the heme groups are brighter red. As a result, oxygenated arterial blood where the Hb is carrying four oxygen molecules is bright red, while venous blood that is deoxygenated is darker red.
The correct answer is cyanobacteria (ancient cyanobacteria).
The huge concentration of oxygen in the atmosphere is believed to have been initially produced by the actions of ancient cyanobacteria. They are usually observed as symbionts with a number of another group of species, like coral, lichens (fungi), Azolla (pteridophytes), angiosperms, and others.
The atmosphere of oxygen was generated by various cyanobacteria at the time of Proterozoic and Archaean periods.
Answer:
According to the Acceptable Macronutrient Distribution Ranges (AMDR), what percentage of total calories should come from carbohydrate?
<u>The answer is</u> "45 to 65 percent"
Explanation:
<u>Carbohydrates</u>:
Carbohydrates are grouped into 3 classes: Monosaccharides, Oligosaccharides and Polysaccharides. Carbohydrates are found in living organisms as they are also known as sugars. They are are the most abundant bio-molecules belonging to class of organic compounds. The breakdown of carbohydrates supplies the principal part of the energy that every organism needs for various important processes. Carbohydrate foods are an important source of fiber and other nutrients.
<u>Acceptable Macronutrient Distribution Range:</u>
Acceptable Macronutrient Distribution Range is the predetermined range of intake for a particular energy source in our diet that is associated with overall health and reduce the risk of chronic disease with the aim of making the intake supply essential nutrients which are important in metabolism, growth, and many other functions. If an individual consumed in excess of Acceptable Macronutrient Distribution Ranges, it raises concerns over a potential increase in the risk of chronic diseases.
Those cells are called neurons
Answer:
either the x or y chromosomes
