Which of the following is classified as a noninfectious disease?

Lysosomes are membrane-bound organelles that contain lysozymes that are responsible for breaking down waste materials and cellular debris through intracellular digestion. This process helps maintain cellular health and homeostasis by recycling and degrading cellular components.

A chlorine molecule contains the fewest covalent bonds among the options provided. It consists of two chlorine atoms bonded together by a single covalent bond. Compared with the other options, ammonia has three covalent bonds, methane has 4 while water has 2.

Helper T cells are important cells that stimulate the action of other immune cells. For instance, they not only help activate B cells to secrete antibodies and macrophages to destroy ingested microbes, but they also help activate cytotoxic T cells to kill infected target cells.

a. Water boils to produce steam at 100°C - This is a phase change (from liquid to gas) and not a chemical reaction of water.

b. Water dissolves sugar - This is a physical change, not a chemical reaction of water.

c. Water produces gas with sodium metal - This reaction involves the chemical reaction of water with sodium metal to produce hydrogen gas.

d. Water and oil separate when combined - This is a physical separation, not a chemical reaction of water.

The inner lining of the uterus is the source of blood and mucosal tissue that is shed during menstruation.

Browning of the apple surface is due to the action of the enzyme polyphenol oxidase. Lemon juice is acidic and lowers the pH of the apple's surface. This inactivates the enzyme polyphenol oxidase, which works best at a neutral pH. This in turn reduces the browning action on the apple.

Biological macromolecules are large organic molecules such as carbohydrates, lipids, nucleic acids, and proteins. They are built from smaller molecules, which are linked commonly by covalent bonds, and these can be broken down.

Rationale

Electrons are subatomic particles that have relatively little mass and are negligible when calculating atomic mass. The atomic number is usually the sum of protons and neutrons in the nucleus of the atom.

Concentration of H+ in the solution = 10 −1 M

pH= -log(10 −1)

pH= -(-1)

=1