The body's nonspecific defiance against invading pathogens is known as innate immunity and includes the following:
mechanical barriers and surface secretions
1. The intact skin and mucous membranes of the body. These provide a high degree of protection against pathogens.
2. The sebaceous secretions and sweat of the skin contain bactericidal and fungicidal fatty acids that can kill bacteria and fungi.
3. Normal bacterial flora of the skin may produce various antimicrobial substances such as bacteriocines and acids.
Humoral defence mechanisms
1. Lysozyme. This is an enzyme found in most tissue fluids apart from cerebrospinal fluid, urine, and sweat. It can kill bacteria.
2. Interferon. Inhibits viruses from replicating
3. Complement. This is a heat labile serum that can destroy gram-negative bacteria.
Answer:
In many cases, the impact of the HIV/AIDS epidemic on families, communities, and countries has feedback effects that influence the course of the epidemic –- for example, poverty and the breakdown of social and economic systems impair community systems that could help to stem the spread of infection.
Explanation:
Knowledge of earth system in order to protect, understand and develop research methods.
A human needs approximately 2-5 percent of protein for the typical energy needed daily. Protein is one of the most important building blocks in the body. It helps the bones, muscles, skin, blood, and cartilage. A humans nails and hair are made of protein. The protein your body uses also repairs tissues and build new ones.
Answer:
The characteristic of water that makes this liquid stick to the side of a test tube is called capillarity (Claim).
Explanation:
Water (H₂O) is a polar molecule with the ability to generate van der Waals forces, which is explained by the 4 hydrogen bonds it forms to bind to other substances. The consequence of the forces of the molecular bonds are four properties of H₂O, including surface tension, cohesion, adhesion and capillarity.
- <u>Claim</u>: The characteristic of water that makes this liquid stick to the side of a test tube is called capillarity.
- <u>Evidence</u>: Cohesion and adhesion of water are properties that come from the forces of the molecular bonds of water, and whose effect is the ability of water to wet surfaces and adhere to a tube that contains it, the latter due to capillarity. Capillarity also allows water to rise through the roots and stems of plants, through their thin vascular ducts.
- <u>Reasoning</u>: <u>cohesion</u> in water depends on the force of attraction between H₂O molecules, <u>adhesion</u> is the capacity of H₂O molecules to join other different molecules and —together with <u>surface tension</u>— make H₂O molecules close to the walls of a glass tube adhere to it, which represents capillarity.
The effect of capillarity is more evident when the test tube is of a smaller diameter, although capillarity and adhesion to its walls always exist, and to a greater degree than any other substance.
