Human Biology: Ch:1

• The smallest independently functioning unit of an organism is a(n) ______.
• A collection of similar tissues that performs a specific function is an _______.

  Organ
• The body system responsible for structural support and movement is the _____.

  Skeletal
• Metabolism can be defined as the____________________.

  Sum of all chemical reactions in an organism.
• Cancer cells can be characterized as “generic” cells that perform no specialized body function. Thus cancer cells lack________.

  Differentiation
• Humans have the most urgent need for a continuous supply of _________.

  Oxygen
• Which of the following statements about nutrients is true?

  a.All classes of nutrients are essential to human survival

  b. Because the body cannot store any micronutrients, they need to be consumed nearlyevery day.c. Carbohydrates, lipids, and proteins are micronutrients.d. Macronutrients are vitamins and minerals

  All classes of nutrients are essential to human survival.
• C.J. is stuck in her car during a bitterly cold blizzard. Her body responds to the cold by____________.

  Breaking down stored energy.
• Which of the following imaging techniques would be best to use to study the uptake of nutrients byrapidly multiplying cancer cells?

  PET
• Which of the following imaging studies can be used most safely during pregnancy?

  Ultrasounds
• What are two major disadvantages of MRI scans?

  High cost and the need for shielding from the magnetic signals
• Where would you place a grain of salt in the six levels of organization?

  At the molecular or chemical level since a sodium ion Na+ and a chloride ion Cl- combine to make NaCl molecule.
• Name the six levels of organization of the human body.

  Chemical, cellular, tissue, organ, organ system, organism.
• Which medical imaging technique is most dangerous to use repeatedly, and why?

  CT scanning subjects patients to much higher levels of radiation than X-rays, and should not be performed repeatedly.
• Explain why ultrasound imaging is the technique of choice for studying fetal growth and development.

  Ultrasonography does not expose a mother or fetus to radiation, to radiopharmaceuticals, or tomagnetic fields. At this time, there are no known medical risks of ultrasonography