In the kidney mechanism for buffering the acidity of the blood, when would hydrogen ions be excreted and bicarbonate ions be reabsorbed?
( ) only when the lung system is not working
( ) when the blood is acidic
( ) when the blood is basic
( ) when the blood is neutral ph, which is not normal
( ) the kidney never excretes or reabsorbs hydrogen and bicarbonate ions.

Explanation:

Kidneys along with filtration of blood maintain the homeostasis in the human body. The kidneys maintain the homeostasis by many mechanisms in which one of the mechanism is to maintain the acid-base balance in the blood.

When the pH of the blood drops below the 7.35 the blood becomes acidic in nature and a condition arises called acidosis. During acidosis, the Hydrogen ion concentration in the blood increases.

To overcome the acidosis, the kidneys excrete the hydrogen ions through the urine and absorb more bicarbonate from the tubular fluid through the tubules. The bicarbonate acts as a buffer and form carbonic acid with hydrogen ions. These hydrogen ions are excreted out with urine.

Thus, the selected option is the correct answer.

question#1

ans:

cell is the basic unit of organization of all living things. cells are often called the building block of life and it is the smallest unit of life. the study of cell is called cell biology. cell consists of cytoplasm enclosed within membrane, which contain bio-molecules such as proteins and nucleic acid.

two third of cell is water, which means that two-third of your whole body is water. the rest is the mixture of molecules, mainly proteins, lipids and carbohydrates.

question#2

ans:

organ:

an organ is a group of tissues specialized to form a functional unit. an example is the heart in animals.

organ system:

an organ system is a group of several organs whose functions are synchronized to release an effective action in a living organism. an example is digestive system.

question#3

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#4

different systems perform different function at tissue level. for example, the respiratory system facilitates breathing. in the alveoli tissue of the lungs, the exchange of oxygen and carbon dioxide molecules between the air and the bloodstream occurs by passive transport, so that oxygen is taken in and carbon dioxide and water are removed. different systems of the body carry out different functions. for example, your digestive system is responsible for taking in and processing food, while your respiratory system—working with your circulatory system is responsible for taking up oxygen and getting rid of carbon dioxide.

question#5

our body works because of the interactions that happen between organs and organ systems.  

for example:  

the heart to regulate blood flow throughout the body. the blood carries oxygen and nutrients to the cells and carries carbon dioxide and waste away from the cells. body systems work together in maintaining a constant internal environment. when this balance is disrupted, the body systems may not function properly, and human health can suffer.   you start to feel bad.