HBio5 - Prokaryotes & Eukaryotes by David Smashey https://padlet.com/david_smashey/3c8yu9r4o5dj I don't understand/would like more information about... en-us 2017-09-26 19:52:07 UTC 2025-10-28 12:44:27 UTC hello@padlet.com What exactly are considered "organells" and what are not? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191734482
That's actually kind of confusing. Some people call any structure in a cell an organelle while others only define them as those that are "membrane-bound,", which leaves out ribosomes, centrioles, and nucleolus (which are not bound (surrounded) by a membrane).

]]> 2017-09-27 15:48:31 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191734482 The theory states that all cells are made up of cells, which is the general conclusion. However, the first cell(s) could not have come from another cell because they were non existant. If a cell must have started without another cell to begin with, couldn't a cell be created like that now? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191742515 That's a key question--there is an active area of research into both early prokaryotic cells (how the first cells arose) and into how the first eukaryotic cells came about (endosymbiotic theory). There are aspects of a cell that have often been created in a lab but certainly no self-sustaining or self-replicating true cell has been made.]]> 2017-09-27 16:05:05 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191742515 What are upper and lower bound cells? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191750635 2017-09-27 16:20:42 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191750635 What was the first type of cell found or created? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191752853 Certainly prokaryotic, but there is debate whether it was bacteria or archaea or something ancestral to both.]]> 2017-09-27 16:25:04 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191752853 What else can affect the size of the cell? 20murrayd https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191753117 It's mostly SA/Vol ratio but there may also be practical limits to have fast proteins can be made to service a cell.]]> 2017-09-27 16:25:32 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/191753117 How did we figure out that the surface area and volume mattered to the size of the cell? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192049460 surface area and volume relationships are important in determining the scale of many things including animals at different latitudes (temperatures).]]> 2017-09-28 13:11:42 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192049460 Are cell membranes, Cell walls, and cytoplasm considered "organells"? if not, what would I call them? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192495332 So, I guess one could generically call all of them cell parts. You will almost always see cell walls included in organelle lists (even though they don't really meet the official criteria). The cytoplasm (or sometimes cytosol) is the medium the other organelles are suspended in.]]> 2017-09-29 15:16:15 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192495332 How do the cells divide? Also, if a Eukaryotic cell divides, how do both pieces gain back the organells it loses when it seperated? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192498768 The chromosomes are divided very carefully and precisely followed by a less careful dividing of the cytoplasm. The first part of the cell cycle after divsion is mostly devoted to the new cells gaining size and adding more organelles.]]> 2017-09-29 15:23:17 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192498768 It says that Eukaryotic cells divide by mitosis, isn't that just the splitting of the cell into two? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192499516 Sort of. Mitosis is really just the precise sorting and division of the chromosomes followed by cytokinesis, which is the division of everything else.]]> 2017-09-29 15:24:49 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192499516 We will study cell division in December. david_smashey https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192501705 2017-09-29 15:29:18 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192501705 What does the table mean by "security" as the factory part of an organell? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192503069 There are some very toxic chemicals that end up in the cell. They don't hurt us at very low concentrations but they would be deadly if they built up. Peroxisomes seek out, take in, and break down these chemicals (like peroxide).]]> 2017-09-29 15:32:16 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192503069 What are some of the molecules that are completely safe to be in the nuclear envelope with DNA https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192503337 Certainly the enzymes that work to copy the DNA for replication and transcription. Coming in November!!]]> 2017-09-29 15:32:53 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192503337 Could stem cells be the cure for cancer? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192503974 Certainly they could contribute. Cancer is so tricky because even though the outcome looks to be in common (uncontrolled growth of malformed cells), the causes are many and varied. Curing cancer is like curing 50-100 different diseases. ]]> 2017-09-29 15:34:12 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192503974 How exactly does a cell divide? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192504347 There is a precise lining up of all the chromosomes then separating. It kind of looks like square dancing of some kind of baroque dance. After the chromosomes divide, the rest of the cell either gets pinched in half (animals) or a new thick cell wall grows in the middle (plants).]]> 2017-09-29 15:34:56 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192504347 how do lysosomes get rid of protein? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192506244 They are full of enzymes that hydrolyze (break) up the bonds. Then we can reuse those amino acids to make new proteins.]]> 2017-09-29 15:39:23 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192506244 What is the most complex part of a cell? 20oconnelj https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192506291 Probably...
Nucleus
mitochondria
chloroplasts (in plants)]]> 2017-09-29 15:39:31 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192506291 Since cancer cells duplicate and grow uncontrollably, are there any studies that have been done accelerate the growth of a cancer cell to see if there's a limit to how far a cell will grow before no longer having the capability of duplicating? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192506474 I don't know. They are already dividing at pretty much the absolute max (since they don't really do anything else). ]]> 2017-09-29 15:39:56 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192506474 Whats MRNA https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192507466 messenger RNA -- it's a temporary copy of one gene that can go out of the nucleus to the cytoplasm where the ribosomes live. Then is serves as the recipe for the ribosome to assemble a protein.]]> 2017-09-29 15:42:05 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192507466 Is the nucleolus also an organell? or would we just call it part of the nucleus? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192508052 It doesn't fit the picky definition of an organelle since it is not membrane-bound. ]]> 2017-09-29 15:43:23 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192508052 Do we know why the smooth ER is more tubular than the rough ER? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192508192 I don't know. I looked online and didn't see an obvious answer. The main difference is that RER is often flattened.]]> 2017-09-29 15:43:40 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192508192 What is the difference between transcription and translation? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192540768 We will study these carefully in the next unit. Transcription is the copying of one gene from a chromosome into a form that can escape the nucleus -- messenger RNA. Once the messenger RNA gets out of the cell, it can be read by ribosomes which use it as the recipe for making a protein. That process is called translation]]> 2017-09-29 16:56:30 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192540768 How does the Golgi Apparatus modify proteins? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192611489 2017-09-29 20:29:22 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192611489 Where do carbs go after they are metabolized? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192619159 2017-09-29 21:21:47 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192619159 Does the rough endoplasmic reticulum actually help make the protein, or is it just a place for the ribosomes to stay and do the work? https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192633764 2017-09-30 01:59:33 UTC https://padlet.com/david_smashey/3c8yu9r4o5dj/wish/192633764