Biology Quiz 3

Gregor Mendel (1822-1884) discovered the basic principles of heredity through experiments with pea plants, long before the discovery of DNA and genes.

The edible part in the onion is concentric fleshy, enlarged and scaly leaf bases.

Corpus luteum (CL) is a yellow hormone-secreting body in the female reproductive system which secretes progesterone. It is a completely normal cyst that forms on the ovary every single month in women of childbearing age. This cyst is actually a group of cells inside ovaries that forms during each menstrual cycle. It appears right after an egg leaves the ovary (ovulation).

By mass, about 96 percent of the human body is made up of just four elements: oxygen (65 percent), carbon (18.5 percent), hydrogen (9.5 percent), and nitrogen (3.3 percent). Oxygen (O) together with hydrogen form water, which is the primary solvent found in the body and is used to regulate temperature and osmotic pressure.

Antigen stimulates the production of antibodies when introduced into a living organism. It is a substance that enters the body and starts a process that can cause disease. The body then usually produces substances (antibodies) to fight the antigens.

Ischemia is insufficient blood supply in the human body. It is a restriction in blood supply to tissues, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive).

The kidney is the organ that excretes water, fat and various catabolic wastes. The kidneys remove waste products called urea from the blood through tiny filtering units called nephrons. There are about one million nephrons in each kidney.

Vertebrae is a series of bones that form the spinal column (backbone) of all vertebrates. The average person is born with 33 vertebrae that interact and connect with each other through flexible joints called facets. By the time a person becomes an adult most have only 24-26 vertebrae because some vertebrae at the bottom end of the spine fuse together during normal growth and development.

The rhizomes of ginger are considered as stems and not as roots as it contains nodes and internodes.

Adrenaline is a neurotransmitter in the sense that, within the brain, it helps neurons to communicate with one another.