BIOL 108 Human Biology
Worksheet 2; Week 2

Answer the following questions and save it as a word document (.doc or .docx are acceptable formats; .wps files cannot be opened by the D2L site and are not to be used) and submit it to Dropbox Worksheet 2 by Sunday of week #2 by midnight Central Standard Time for full credit. When the question asks you to explain, describe, or detail something, make sure you completely answer the question for full credit. Late worksheets will receive 20% off per day late; after five days late it is an automatic zero. One submission per assignment only; I will grade the first submission in the dropbox, once an assignment has received a grade, it cannot be re-submitted for a higher grade.

1. Define a cell: A cell is the basic structural and functional unit of all organisms which exist as independent units of life or may form colonies or tissues in higher plants and animals

2. Identify the two basic types of cells: Eukaryotes (having a nucleus) and prokaryotes (without a nucleus)

3. Explain the basic organization of a plasma membrane: The plasma membrane is composed of a phospholipid bilayer which is embedded by proteins. The phospholipids are part of the outward surface and inside surface of the membrane.

4. What is a”selectively permeable “membrane? It is a membrane in cells that only allows certain molecules and ions etc in.

5. Define diffusion and osmosis. Diffusion is the process by which molecules spread from areas of high concentration, to areas of low concentration and Osmosis is the diffusion of water across a membrane

6. What is a similarity between osmosis and diffusion? Both involve movement of particles from higher concentration to lower concentration and both occur in both living and non living things

7. Explain what happens to a cell when placed in isotonic, hypotonic and hypertonic solutions. When a cell is placed in an isotonic solution the cell remains its normal size, when place in a hypotonic solution the cell it expands and gets larger and when placed in a hypertonic solution it gets smaller or shrinks.

8. Identify a similarity and difference between facilitated transport and active transport. The differences is that in facilitated transport molecules are transported from higher to a side of lower concentration and in active transport the molecules move from lower to higher. The similarities are that they both involve the transport of molecules.

9. What is the function of a lysosome, Golgi apparatus and mitochondrion? Lysosome transports undigested material to cell membrane for removal, Golgi apparatus is involved in processing, packaging and secretion and mitochondrion recycles and decomposes proteins, fats, and carbohydrates, and forms urea

10. What structures are associated with cell movement? Microtubules and actin filaments are the structures associated with cell movement.

11. What is the difference between rough and smooth ER? What type of macromolecule do each produce? The difference between rough ER and smooth ER is that rough ER is studded with ribosomes (the molecules where proteins are made) and smooth ER- termed smooth because it does not have any ribosomes and its smooth appearance under a microscope

12. What three fibers are associated with the cytoskeleton? Microtubules, actin filaments, and intermediate filaments

13. What is the function of cellular respiration? The function of cellular respiration is to break down molecules and generate or produce ATP.

14. What vital function does oxygen serve in the human body? Oxygen helps metabolize food, and is used as fuel to burn glucose which helps our body produce energy. Cells also use oxygen to produce ATP.

15. List and describe the three major steps in cellular respiration. The three major steps are glycolysis which involves the breaking down of glucose molecules from carbohydrates into molecules of pyruvate, the citric acid cycle which completes the