21) The type of muscle tissue that can be under our conscious control is:

A) skeletal.

B) cardiac.

C) smooth.

D) skeletal and smooth.

E) smooth and cardiac.

22) Which of the following is characteristic of cardiac muscle?

A) It is found only in the heart and blood vessels.

B) It is most similar in appearance to smooth muscle.

C) It is not striated.

D) It contracts under the control of its pacemaker cells.

23) Glial cells are cells found in which type of tissue?

A) muscle

B) nervous

C) connective

D) epithelial

24) In the textbook, the stomach was given as an example of an organ. Which of the following is a valid description of the work of one of its tissues?

A) Its connective tissue helps drain the stomach contents.

B) Its muscle tissue forces secretions out of glands and into the stomach.

C) Its epithelial tissue secretes substances that help with digestion.

D) Its nervous tissue communicates directly with the intestines to coordinate digestion.

25) Which of the two systems listed work together to bring oxygen into your body and deliver it to your cells?

A) lymphatic and endocrine

B) respiratory and cardiovascular

C) respiratory and digestive

D) urinary and cardiovascular

26) Which of the following systems are involved in coordination and regulation?

A) nervous and endocrine

B) digestive and cardiovascular

C) urinary and cardiovascular

D) lymphatic and respiratory

27) Which of the following systems are involved in bringing nutrients into the body and to its cells?

A) respiratory and cardiovascular

B) digestive and cardiovascular

C) urinary and cardiovascular

D) lymphatic and respiratory

28) Which human body system would be best described as playing roles in both waste disposal and conservation?

A) cardiovascular

B) nervous

C) urinary

D) lymphatic

E) respiratory

29) Which human body system includes lymphatic organs of the lymphatic network, such as the tonsils and lymph notes?

A) nervous

B) cardiovascular

C) urinary

D) endocrine

E) immune

30) Structures such as hair and nails are part of the:

A) skeletal system.

B) integumentary system.

C) endocrine system.

D) muscular system.

E) lymphatic system.