Unit 1 Cell Biology

• Explain the process of focusing on a specimen with a microscope.

  1. raise stage with coarse adjustment knob

  2. move stage so that specimen is in view

  3. use coarse, then fine adjustment knob to focus

  4. change objective but don't touch adjustments

  5. use fine adjustment knob to focus
• Explain the process of making a wet mount

  1. Drop liquid onto slide and specimen

  2. Slowly place cover slip on top, lowering it at a 45 degree angle

  3. Lightly tap the cover slip to get rid of any bubbles
• What are the rules for a biological drawing?

  - use a sharp pencil

  - don't use shading

  -use clear, continuous lines

  -draw what you see

  - label all relevant structures

  -use a ruler for label lines
• What is the formula for calculating magnification?

  Magnification= Image Size / Actual Size
• List the rules of the cell theory

  1. All living things are made of cells

  2. cells are the smallest units of life

  3. cells only come from existing cells
• How does striated muscle challenge the cell theory?

  consists of muscle fibers as building blocks, much larger than most animal cells
• How does aseptate fungal hyphae challenge the cell theory?

  contain no septa (cross walls that divide organisms into cell-like sections). each hzpha is a tube-like structure with many nuclei
• How does giant algae challenge the cell theory?


  algae are single-celled, even giant algae. Can be up to 100 mm in length and still have only one nucleus.
• What are the functions of life that all cells carry out?

  metabolism, response, homeostasis, growth, reproduction, nutrition, defense
• Cell function of life: Metabolism


  chemical reactions inside the cell, including cell respiration to release energy
• Cell function of life: Response

  perceiving and responding to change in environment
• Cell function of life: Homeostasis


  keeping conditions inside the organism within reasonable limits
• Cell function of life: Growth


  an irreversible increase in size
• Cell function of life: Reproduction

  producing offspring sexually or asexually
• Cell function of life: Nutrition


  obtaining food to provide energy and the materials needed for growth
• Cell function of life: Defense


  protection against enemies
• Chlamydomonas: Homeostasis


  contractile vacuoles will with water, expel through membrane (maintains water levels)
• Chlamydomonas: Reproduction


  asexual reproduction and sexual reproduction
• Chlamydomonas: Metabolism


  contains enzymes catalyzing chemical reactions
• Chlamydomonas: Response


  eyespot is able to detect light, cell moves toward light
• Chlamydomonas: Growth


  able to grow through absorption of materials and photosynthesis
• Chlamydomonas: Nutrition


  contains a chloroplast, produces its own food through photosynthesis
• Paramecium: Reproduction


  asexual and sexual reproduction
• Paramecium: Metabolism


  enzymes in cytoplasm catalyze chemical reactions
• Paramecium: Homeostasis


  contractile vacuoles fill with water, expel it through plasma membrane (maintains water levels)
• Paramecium: Response


  cilia help cell to move around, cell moves toward or away from external stimuli
• Paramecium: Growth


  nutrients from digestion use for energy and materials for growth
• Paramecium: Nutrition


  ingests small organisms, digests through endocytosis
• What part of the cell is represented by the surface area?

  the plasma membrane
• The rate at which materials cross the plasma membrane depends on the cell's ________________________________

  surface area
• the metabolic rate of a cell is proportional to its ___________________________

  volume
• As the cell gets larger, the surface area to volume ratio gets ________________________

  smaller
• When the cell gets larger, the exchange processes of the cell get _____________________

  less efficient
• What happens when a cell gets too big, how does it maintain efficiency of exchange processes?

  the cell divides and makes more cells
• What are the pros and cons of using a light microscope?

  Pros: 0.2 micrometer resolution, reveals the structure of cells, shows in color

  Cons: resolution limited by the wavelength of light
• What are the pros and cons of using an electron microscope?

  Pros: much higher resolution than light microscope, electron beams have much shorter wavelengths, 0.001 micrometer resolution, reveals the ULTRAstructure of cells

  Cons: only shows in black and white
• How would our knowledge of cells be different if electron microscopes hadn't been invented?

  we would not know about the ultrastructure of the cell. We wouldn't know about ribosomes, lysosomes, and rough ER
• plasma membrane


  The membrane at the boundary of every cell that acts as a selective barrier, thereby regulating the cell's chemical composition.
• cell wall


  A rigid structure that surrounds the cell membrane and provides support and shape to the cell
• fimbrae


  structures on the surface of bacteria used for adhesion