According to the starling law, parasympathetic effects on cardiac rate and contractility include decreasing the rate of contraction and increasing the filling time resulting in a stronger contraction.
The Frank-starling law of the heart states that the stroke volume of the heart increases in response to an increase in the volume of blood filling the heart when all other factors remain constant.
An example is a radio wave
Approximately one billion oxygen molecules. that is because there are about 250 million molecules of haemoglobin in each cell, and each haemoglobin molecule binds to 4 oxygen molecules
Answer:
Iron, Magnesium, and Nitrogen
The question is incomplete. Th ecomplete question is as following:
All of the following protect the skin and mucous membranes from infection EXCEPT
A) multiple layers of cells.
B) tears.
C) saliva.
D) HCl.
E) the "ciliary escalator."
Answer: D) HCl.
Explanation:
- The epidermis, the outer layer of the skin provides waterproofing and serves as a barrier to infection and other laers also sustain any type of injury.
- Tears wash out foreign bodies which enter the eye. In addition, tears contain a substance called lysozyme which has an antibacterial function and works to prevent microbial invasion and infection.
- Saliva protects against infection, especially via the innate immune system. This mechanism is an important first-line protection against bacterial and viral infection
- The mucociliar escalator is within the conducting airways and is composed of mucus and cilia that transfer the mucus up and out of the lungs where it can be removed by coughing or swallowing,
Whereas HCL helps in the digestion process.
Hence, the correct option is D.
