level: Module 2
Questions and Answers List
Week 2
level questions: Module 2
| Question | Answer |
|---|---|
| A scientific discovery that isolates specific cell components so that their function can be studied and learned from... | Cell Fractionation |
| a eukaryotic cell houses it's DNA where?.. | Nucleus -- had a double membrane |
| a prokaryotic cell houses it's DNA where?.. | Nucleoid -- no membrane around |
| what is the purpose of the endomembrane system? | To synthesis proteins and transport them to their respective organelles |
| What does the smooth reticulum do? | makes lipids, metabolizes carbs, detoxifies drugs and poisons as well as phospholipids, oils and steroids |
| What kind of protein is found to be secreted by the rough reticulum that has a carbohydrate component covalently bonded to it? | glycoprotein |
| what does the golgi apparatus do in a cell? | its a center for manufacturing, warehousing, sorting and shipping |
| a sac of hydrolytic enzymes that help an animal go through the digestive process of eating.. | lysosome |
| What does phagocytosis do to a cell? | It opens a food vacuole that fuses with a lysosome enzyme that helps the animal metabolize macromolecules. |
| How can a lysosome be involved in autophagy? | The lysosome will attach to the outer membrane of the vesicle, digesting the macromolecules and returning the organic monomers to the cytosol for RESUSE. this is what autophagy means. REUSE/RECYCLE |
| In what are contractile vacuoles found and what is their function? | to pump excess water out of the cell to maintain the appropriate concentration of ions and molecules inside the cell |
| what does mitochondria do?.. and no.. it's not just the power house of the cell | sites of cellular respiration, using oxygen to generate ATP by extracting energy from sugars, fats, and other fuels |
| What do chloroplasts do? | convert solar energy to chemical energy by absorbing sunshine and using it to synthesize new organic compounds |
| Where can DNA be found other than the nucleus? | mitochondria & chloroplast |
| Where and what are cristae? | Found in the mitochondria and separate the inner and outer membrane from one another |
| Where and what are stroma, thylakoids and grana? | Stroma: fluid filled space in chloroplast where the thylakoids and grana are found Thylakoids: convert light to energy -- very critical Grana: the stalks over thylakoids |
| glyoxysomes.. what are they? | they are specialized peroxisome -- peroxisome are enzymes that have the ability to break down a hydrogen peroxide molecule into just water.-- that change the fatty acids into sugars that can then be used as energy |
| what does the cytoskeleton consist of?.. | The cytoskeleton is a network of fibers extending through the cytoplasm that provides mechanical support and maintains the cell’s shape |
| The cytoskeleton consist of three types of fibers, what are they and what are their purpose? | Microtubules shape and support the cell and serve as tracks to guide motor proteins Microfilaments have an ability to branch, bear tension and resist pulling forces within the cell Intermediate filaments purpose is to bear tension near the nucleus and it's lamina |
| Since animal cells don't have cell walls, what do they have that hosts a variety of proteins that help the cell survive? | the complex extracellular matrix |
| In the ECM, fibronectins are found. What is it that they attach to on the surface membrane of the cytoskeleton? | Integrins |
| What are the three types of intercellular junctions found in animal cells? | Gap junctions, tight junctions, desmosomes -- read about this in 2.6 -- they're important and easy to confuse. don't over think them though. |
| What can be labeled as a fluid mosaic model? | the phospholipid bi-layer that has proteins imbedded into its membrane. -- expand a little more on this one -- 2.7 |
| What does being "amphipathic" mean? | Having hydro-loving (hydrophilic) and hydro-hating (hydrophobic) regions -- this is useful when it comes to the surface membrane of |
| What are the 6 functions of the proteins within the phospholipid bi-layer? | Transport , catalyzing metabolic pathway, Signal transduction - hormonal messaging , Cell-cell recognition, Intercellular joining of adjacent cells with gap or tight junctions, structure support within membrane |
| What facilitates the transport of water into and out of the cell through the bi-layer? | aquaporins |
| what is the difference between osmosis and diffusion? | one is the diffusion of particles from high to low using air as its medium and osmosis is the diffusion of water across a selectively permeable membrane |
| What is tonicity? | concentration of solutes that cannot cross the membrane relative to the concentration of solutes in the cell |
| what are three different situations a cell can be placed in, in regards to setting | isotonic, hypertonic, hypotonic -- learn the difference in 2.8 IMPORTANT TOPIC |
| what is osmoregulation? | the regulation of water in and out of a cell. |
| How are gated channels activated? | depends on the presence or absence of an electrical, chemical, or physical stimulus -- more at the end of 2.8 |
| What does active transport help accomplish? | enables a cell to maintain internal concentrations of small molecules that would otherwise diffuse across the membrane. *hint: enables a cell to maintain internal concentrations of small molecules that would otherwise diffuse across the membrane. |
| what does the sodium potassium pump do -- in a short answer | exchanges sodium ions for potassium ions across the membrane. -- more in 2.9, I will also go over this in the session tomorrow |
| When a cell is running low of a specific product, what does it do in order to solve its problem. | hint answer: buy in bulk -- which is basically what receptor mediated endocytosis is |