Anatomy and Physiology Exam 1: Chapters 1-3 Questions With Verified Answers

Understand the body's hierarchy of complexity. What are the different levels and how do they relate to one another? - Answer o Organism composed of organ systems o Organ systems composed of organs o Organs composed of tissues o Tissues composed of cells o Cells composed of organelles o Organelles composed of molecules o Molecules composed of atoms What are the characteristics of life? - Answer Organization Cellular composition Metabolism Responsiveness Homeostasis Development Reproduction Evolution What does organization mean? - Answer living things exhibit a higher level of organization What does cellular composition mean? - Answer Living matter is always compartmentalized into one or more cells What does metabolism mean? - Answer Sum of all internal chemical change: anabolism, catabolism, and excretion What does responsiveness and movement mean? - Answer Sense and react to stimuli What does homeostasis mean? - Answer The body's ability to detect change, activate mechanisms that oppose it, and thereby maintain relatively stable internal conditions What does development mean? - Answer differentiation and growth What does reproduction mean? - Answer Producing copies of themselves; pass genes to offspring What does evolution mean? - Answer mutations: changes in genetic structure What characteristic do viruses lack, making them nonliving things? - Answer They do not possess a cell membrane or a metabolism What are some examples of the body maintaining homeostasis? - Answer Negative feedback causes shivers from temperature change Positive feedback causes contractions during child birth What are dynamic equilibrium and set point? - Answer Body senses a change and activates mechanisms to reverse it within a limited range around a set point What is a negative feedback loop? Give examples - Answer It alters the original changes that triggered them and keeps the variable close to the set point Examples of negative feedback loop: - Answer If too warm vessels dilate in the skin and sweating begins Another example of negative feedback loop: - Answer Blood pressure: Baroreceptors in the arteries near the heart alert the cardiac center in the brainstem. The cardiac center sends nerve signals that increase the heart rate and return the blood pressure to normal and regulates the heart rate Why is homeostasis important to maintain? - Answer Loss of homeostatic control causes illness or death What is a positive feedback loop? - Answer A self-amplifying cycle- leads to a a greater change in the same direction Produces rapid changes Examples of positive feedback loop: - Answer Childbirth, blood clotting, fever What are the 6 elements that make up most of the human body? - Answer Carbon, nitrogen, oxygen, hydrogen, calcium and phosphate What is an element? - Answer The simplest form of matter to have unique chemical properties What is a mineral? - Answer Inorganic elements extracted from soil by plants and passed up the food chain to humans What is an ion? - Answer A charged particle with an unequal number of protons and electrons What is an electrolyte? - Answer Salts that ionize in water and form solutions capable of conducting an electric current