Exam 1 Overview Chapter 1 1. Levels of Organization a. atomic level a.i. atoms in combination are molecules b. Molecular level b.i. molecules to cells c. Cellular level c.i. plasma membrane traps fluid, (organelle level), within cells we have sub structure d. Tissue level d.i. combining cells, a combination of cells are tissues e. Organ level e.i. combine two or more tissues with a function to the human body is organ f. System level f.i. combine many organs under one function (cardiovascular system) g. Organism level g.i. combine all systems (11) and we got systems working in unison 2. Reductionism vs. holism a. Reductionism is breaking down something you don’t understand (like opening up a computer to see how it works) a.i. Example: Medical doctor b. Holism is the approach of looking at something at the whole (like looking at a computer tower to see how computers work) b.i. Example: D.O. (Medical field)
b.i.1. Taking a more systematic approach by looking at everything by the whole. 3. Homeostasis a. adaptation to the environment b. Autoregulation b.i. Occurs when a cell, a tissue, an organ, or an organ system adjusts its activities automatically in response to some environmental change. b.ii. For example: when oxygen levels decline in a tissue, the cells releases chemicals that dilate local blood vessels. Vasodilation increases the rate of blood flow and provides more oxygen to the region that needs it. c. Extrinsic Regulation c.i. Results from the activities of the nervous or endocrine system c.ii. For example: when you exercise, your nervous system commands that increase your heart rate so that the blood will circulate faster, decreasing the blood flow circulation to other organs like the digestive tract. d. Three components to homeostasis d.i. Receptor d.i.1. A sensor that is sensitive to a particular environmental change (stimulus) d.ii. Control Center d.ii.1. Recieves and processes the information supplied by the receptor and sends out commands d.iii. Effector d.iii.1. A cell or organ that responds to the commands of the control center and whose activity either opposes or enhances the stimulus e. requires a lot of energy to stay in organized matter for a human body e.i. Example: we eat food, so we stay energized f. if you have a disruption in homeostasis you have a disease g. If your internal conditions don’t meet with the environment, you die. g.i. Example: maintaining body temperature to meet with environment
h. there is no set point because of the constant changes i. Negative Feedback i.i. works in contrast to keep balance in body i.ii. Example: consuming a meal of high sugars, so body releases insulin to your body to decrease blood glucose j. Positive feedback j.i. An initial stimulus produces a response that exaggerates or enhances the change in the original conditions, rather than opposing it.