Key Concepts: Cell Theory, Cell Structure & Function, Prokaryotic vs. Eukaryotic, Cell Membrane, Microscopes, Passive vs. Active Transport, Diffusion, Osmosis, Energy (Potential vs. Kinetic), Photosynthesis & Cell Respiration (Aerobic vs. Anaerobic), Fermentation (Lactic Acid & Alcoholic) 1. Describe one similarity and one difference between the two terms in each of the following pairs: a. Eukaryote, prokaryote Eukaryote: Has a membrane-bound nucleus in the cell Prokaryote: No nucleus, DNA free-floating in the cell, can have flagellum Both: have cell membranes, have DNA, have ribosomes b. Cell wall, cell membrane Cell wall: rigid, not as flexible, more selective (harder for things to pass through) Cell membrane: fluid, flexible, selectively permeable Both: enclose cell, facilitate what goes in/out of cell c. Diffusion, facilitated diffusion Diffusion: movement of particles from high to low concentration Facilitated diffusion: movement of particles through channel proteins Both: are passive transport (no energy required), particles move from HIGH to LOW 2. Describe the structure of a phospholipid bilayer. There are 2 layers of phospholipids (consisting of hydrophilic heads and hydrophobic tails) 3. Explain the following diagram using the terms: diffusion, cell membrane, low concentration, energy, high concentration. The water molecules are moving across the cell membrane to reach a state of equilibrium. The molecules move from HIGH to LOW concentration, so they move downwards across the membrane. This is an example of diffusion, or passive transport - this does not require energy because it is fueled by the difference in concentrations. 4a. What is the microscope magnification of the eye piece? scanning? low power? high power? ● Eye piece = 10x ● Scanning = 4x ● Low power = 10x ● High power = 40x b. If you were looking at an onion cell using the high power lens, what is the TOTAL MAGNIFICATION at which you are looking at the cell? High power = 40x Eye piece = 10x 40 x 10 = 400x Your total magnification would be 400x using the higher power objective lens. 5. Identify the difference between hypertonic, isotonic, and hypotonic solutions: A = isotonic B = hypotonic C = hypertonic 6. How is active transport different from diffusion and facilitated diffusion? ● Active Transport = requires energy, molecules are forced AGAINST the gradient from LOW to HIGH concentration ● Diffusion = does not require energy, molecules move from HIGH to low concentration ● Facilitated diffusion = does not require energy, molecules move from HIGH to low concentration, but it requires the help of channel proteins (typically larger molecules) 7. Explain what is happening in the following picture. This is an example of ENDOCYTOSIS (Active Transport) - there is a chemical/nutrients being taken into the cell when it’s engulfed by the cell membrane (becomes a vesicle). 8. What is the difference between potential and kinetic energy? Give an example of each. a. Poyential energy - stored energy; e.g,glucose, a ball at the topof ahill b. Kinetic energy - energy of motion e.g., a car onthe freeway 9. Write out the full chemical reaction for PHOTOSYNTHESIS. What organelle is responsible for this? Chloroplast 10. Write out the full chemical reaction for CELL RESPIRATION. What organelle is responsible for this? Mitochondria 11. If we are at 400X magnification (field diameter is 450 micrometers), and there are 10 cells that fit across the diameter of what we’re seeing, what is the estimated size of ONE cell? 450 nanometers / 10 cells = 45 nanometers per cell 12. What is the role of the stomata? What is the role of the guard cells? Stomata role isgas exchange to let oxygen and carbondioxide pass through, as needed for key processes such as photosynthesis and cellular respiration. Guard cells arepairs of cells that surround the stomata and controlgas exchange by regulatingthe openingand closure of stomata. 13. What would cause guard cells to swell and open stomata? What would cause guard cells to shrink and close stomata? → Whentheplanthas anexcess of water, theguard cells swell and create anopeningfor the exchange ofgas → Whentheplanthas a lack of water, theguard cells shrink and close the openingfor the exchange ofgas 14. In fermentation, what relationship exists between the amount of available sugar and amount of carbon dioxide produced? → As more sugar is available, there will be more fermentationthathappens, and more carbondioxideproduced → There is a direct relationshipbetweenthose two factors 15. List the # of ATP produced by each of the following: Glycolysis = 2 ATP Krebs = 2 ATP ElectronTransport = 34 ATP 16. Explain one example of lactic acid fermentation. Explain one example of alcoholic fermentation. a. Lactic acid fermentation- heating milk and combiningit withtwo live bacteria cultures, resultinginthe bacteria breakingdownthe sugars in milk and releasinglactic acid (distinct tart/sour taste) b. Alcoholic fermentation- yeast and bacteria beingadded to tea and fruit (sugar), resultinginkombucha withethanol and carbondioxide bubbles

Photosynthesis

The process by which green plants and some organisms use sunlight to synthesize foods with the help of chlorophyll.

Cellular Respiration

A set of metabolic reactions that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP).

Ecosystem

A biological community of interacting organisms and their physical environment.

Biodiversity

The variety of life in the world or in a particular habitat or ecosystem.

Homeostasis

The ability of an organism or cell to maintain internal equilibrium by adjusting its physiological processes.

Food Chain

A linear sequence of organisms through which nutrients and energy pass as one organism eats another.

Producer

An organism, typically a plant, that can make its own food through photosynthesis.

Consumer

An organism that relies on other organisms for food, divided into primary, secondary, and tertiary consumers.

Decomposer

An organism that breaks down dead or decaying organisms, thereby recycling nutrients back into the ecosystem.

Niche

The role or function of an organism or species within an ecosystem, including its habitat, resource use, and interactions with other organisms.