Answer:
A buffer is simply a mixture of a weak acid and its conjugate base or a weak base and its conjugate acid. Buffers work by reacting with any added acid or base to control the pH.
Explanation:
16 percent of the world's population and 50 percent of the Christians population.
Answer:
the correct order of events in the nutritional processing of this food is ingestion- digestion- absorption- egestion.
Explanation:
1.) Ingestion involves taking food, drink, or another substance into the body by swallowing to aid in digestion.
2.) Digestion involves the breakdown of large insoluble food molecules into small water-soluble food molecules so that they can be absorbed into the watery blood plasma.
3.)Absorption involves the in take of the digested food into the bloodstream
4.) Egestion involves the removal of undigested food substance from the body.
Answer:
C. Oxygen concentration decreases as altitude increases
Explanation:
Higher altitudes have lower levels of oxygen and decreased air pressure.
Answer:
The animals present body structure is due to evolution. It is seen in each part including the structure of the heart. The vertebrate heart becomes complex from a simpler form.
Invertebrates, the heart of fishes is two-chambered having one auricle and one ventricle. The deoxygenated blood gets purified in the gills. They are aquatic and no lungs for breathing. The hearts pump a mixture of oxygenated and deoxygenated blood to the body.
The amphibians and reptiles have 3 chambered heart as they lead terrestrial mode of life. The gills modified into the lungs. The left auricle receives pure blood and the right auricle receives deoxygenated blood. The blood purified in the lungs and in the ventricle, both types of blood get a mix. The ventricle pumps the mixed-blood throughout the body.
In the case of birds and mammal, the heart is 4 chambered and the oxygenated and deoxygenated blood are separated. These two are higher vertebrates. No mix of pure and impure blood, the body receives only the oxygenated blood.
This shows to construct the phylogenetic tree of vertebrates - the fishes should be in the bottom, and above it amphibians, reptiles, then, mammals and birds on the top branch of the tree. As the chambers and structure of the hearts modified one after another.