The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
Answer:
The 4 macromolecules are nucleic acids, carbohydrates, proteins, and lipids.
structure: Carbohydrates, lipid, and protein
Function: Nucleic acids, Carbohydrates, Lipid, and Protein
Explanation:
Well a person breathes harder when he/she exercizing because you are working hard and your body is not used to it so your trying to pass more air through the lungs
Answer:
The purpose of the carbon cycle is to utilize the carbon by the organisms such as plant which uses carbon in the form of carbondioxide for making food. This carbon is stored in the form of glucose. When this food is eaten by the animals, it is broken down into simpler substances and carbondioxode is released in the atmosphere again.
Some carbon is present in soil which is used by microorganisms such as bacteria. So carbon cycle is very important for the survival of life on earth.
