Connect the terms with their corresponding explanations. The terms are presented in a chronological order - the number before an explanation refers to the chapter where the term is introduced.

Choose the terms from the following list:

10. The organ that processes and breaks down substances such as alcohol.
10. The container that stores urea produced by the kidneys.
10. The organ that filters urea from the body.
10. A medical condition characterized by low blood sugar.

11. The material secreted by an endocrine gland.
11. The part of the brain that regulates the function of the endocrine glands.
11. An endocrine gland that produces and secretes insulin.
11. An endocrine gland that produces and secretes adrenaline.

12. The long part of the nerve cell that transports messages from the cell's center.
12. The place where two nerve cells meet and information is transmitted with neurotransmitter substances.
12. A "cable" that is formed by many axons and nerve cells that have joined together.

13. The long part of the central nervous system, protected by the spine.
13. The part of the brain that regulates muscle function.
13. The part of the brain that regulates breathing.
13. A quick, involuntary muscle action.


14. The transparent, outermost surface of the eye.
14. The dark center of the eye.
14. The colorful part of the eye that regulates the amount of light that enters the eye.
14. The part of the eye that contains the receptor cells.
14. The part of the eye that refracts light the most.

15. The tube through which sound waves reach the eardrum.
15. The tube through which the middle ear is connected to the throat.
15. The auditory organ located in the inner ear.

16. The sense that is used to measure the quality of air and food, for example.
16. The sense that is located in the fingertips.


17. A male sex cell. 
17. A female sex cell.
17. The birth place of the male sex cells.
17. The birth place of the female sex cells.
17. A chromosome that is found only in male cells.
17. The exterior part of the male reproductive system used during sexual intercourse.
17. The part of the female reproductive system where the embryo and the fetus develop.
17. A phenomenon where the mucous membrane of the female uterus is removed from the body.
17. A phenomenon where the sperm cells leave the penis.

18. A phenomenon where an egg cell leaves the ovary.
18. The part of the female reproductive system where fertilization often takes place.
18. A developmental stage that precedes the fetus.
18. An organ that grows in the uterus of the pregnant mother.