BIOLOGY A LEVEl
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BIOLOGY A LEVEl - Details
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199 questions
| 🇬🇧 | 🇬🇧 |
| What is the liquid part of the cytoplasm called? | Cytosal, where the enzymes catalysed reactions happen in the cell |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What is the cell membrane made up of? | Phospholipid bilayer |
| What is the liquid part of the cytoplasm called? | Cytosal, where the enzymes catalysed reactions happen in the cell |
| What is the outside of the double membrane nucleus called | Nuclear envolope |
| What are the holes in the nuclear envolope called? | Nucleur pores, allows larger molecules to leave the nucleus |
| If we want to release protein what do we need | We need to use the genetic code in dna, to do this, we need to make a messenger RNA, as the actually dna is too big to go out |
| The rough endoplasmic reticulum is connected to what? | Nucleur envolope, it has many ribosomes on them named 80s |
| Where are the ribosomes made? | In the grey area of the nucleolos |
| Describe the journey of the messenger RNA in the RER | The MRNA travels in the sacs of the RER called cisternae, as it goes through it connects with a ribosome as a sight of protein synthesis |
| What do the ribosomes do to the messenger RNA | The MRNA uses the code from the DNA, the ribosomes take that code and turn it into a polypeptide chain |
| Where will protein get modified and proccessed | The golgi apparatus |
| What is the SER | The SER has no ribosomes, they are contiunous with the RER |
| What is the function of the SER | Synthesise lipids (including cholestorel), once the lipids are synthesised they will also go into a vesicle and travel and merge with the golgi |
| How do the polipepties travel in the golgi apparatus | They travel from left to right through every one of the sausage looking organelles, until it reaches the end where it will now be proccessed and modified |
| What happens after modification. | The proccessed vesicale can go where it needs to go |
| What can the vesicle do when it is processed. | Can fuse out the cell membrane, if the vesicle is an enzyme we would call it a lysosome, it can go anywhere in the cell |
| What are centrioles made out of | Microtubes, they come in 9 sets of of 3 |
| What is the cytoplasm structure | Scaffolding that spreads around the cell, the vesicle can use this to get where it wants |
| What is the mitochondria | Another double membrane, inside the mitochondria is ribosomes but smaller (these are called 70s) |
| What is the mitochondria used for? | DNA in the mitochondria is used to code for enzymes, ATP is made in mitochondria. allows for exocytosis and endocytosis |
| What do the cell wall contain? | Other polysaccharides |
| What is the cell membrane surrounding the vacuole | The tonoplast |
| If we draw 2 cells together? what is the middle part called | The middle lamella |
| What are the holes between the 2 cells | Plasmodona so the cell membrane is continous. |
| What are the structures sticking out of the bacteria cells | Pillai, help the cell stick to surfaces |
| What is the cell wall made out of in a bacteria cell | Peptidoglycan (murein), made out of peptides and sugar |
| What do some bacteria cells have | Have an outside protection named a capsule, prevents dehydration and toxins |
| These bacterias need nutrition, how are they going to get the nutrient from the food molecule. | The bacteria cells need enzymes to break down (which are made in ribosomes) |
| What do we need to tell the ribosomes what amino acids need to be study together, | We need to get a code, we get this from DNA |
| What do bacteria cells NOT have but the animal and plant cells have. | There are no membrane bound organelles. |
| We need to _____ the DNA | Transcribe the DNA to the Messenger RNA (mRNA) |
| At the ribosomes, what happens to the mRNA | Translation will take place to produce a protein, which will self assemble and end up with a little tiny enzyme, it would make hundreds of enzyme molecules |
| What was the hundreds of tiny enzymes do after? | They will go out of the bacteria cell to digest this food molecule |
| What is the yoyo like structure in the nucleus | Chromatin - and is what the chromosomes are made out of chromosomes |
| What does the RER and the SER do in relation to the nucleus | It surrounds the nucleus |
| What is another function of the golgi apparatus | Extracellular transport |
| What does the SER produce. (vesicle) | Secretary vesicles that fuse with the cell surface membrane and releases contents via exocytosis |
| How large is the mitochondria | 3rd largest organelle |
| What hdoes the inner membrane do in the mitochondria | The innermembrane is folded --> increasing the surface area |
| What is cristae | The interfolding of the innermbranes |
| What does lysosomes contain | Contains hydrolytic enzymers --> catalyses hydrolysis |
| What is the function of the lysosomes | Apoplyosis --> cell suicide and it digests cells |
| How large is the chloroplasts | 2nd largest organelles, it contains a double membrane |
| Explain the inner membrane of the chloroplasts | The inner membrane is folded forming granum which are made up of thylakoids --> increases surface area |
| What is the function of the plasodesmata | Allows substances to pass from cell to cell without having to go through the cell wall or the cell membrane |
| How big is the prokaryote cell | Generally 1 -5 micro metres in diameter, contains 70s ribosomes |
| What are the gaps used for in between the phospholipid bi - layer. | Carrier proteins and transport proteins or just normal protein - these are examples of transmembrane proteins. |
| If they imbedded into the membrane, what is it called? | Integral proteins |
| What must these proteins have? | Hydrophobic and hydrophilic parts. |
| What can be attatched to these proteins? | Carbohydrates |
| What are glycoproteins and glycolipids used for | They are both receptors can be involved in singaling they might recognize hormones or neurotransmitters, can be antigen in recognizing other cells |
| What do the glycoproteins do also? | Help determine the shape of the cell |
| What can the channel proteins do | For ions (such as sodium ions) to safely pass through, they have to go through the channel because they can't go through the phospholipid as its hydrophobic |
| What happens if the phospholipids are spread out? | The ions can pass through the layer, this is what happens when a membrane is more FLUID than it should be (you end up with gaps), so the membrane will be too permeable but you also dont want it to be too rigid |
| What happens if the phospholipids are too rigid? | They wont be fluid enough the glycoproteins cannot move around and the membrane might stop working |
| What affects the fluidity of membrane pt 1? | Unsatured fatty acids in the phospholipids, the tail will be spread out so the next phospholipid will not be as close to it, as a result they are further apart making them more fluid |
| What affects the fluidity of the membrane pt 2? | The temprature, like butter at hotter tempratures it will become a fluid, just like the phospholipid, and when cooled down it will become harder and more RIGID. |
| How do we keep the fluidity normal in the phospholipid bi - layer. | They add a molecule between the phospholipids called cholesterol into the bi layer |
| What happens when the temprature goes up (with cholesterol involved) | The cholesterol interacsts with the fatty acid to reduce the fluidity of the cell membrane |
| What would an increased magnification do to the resolution. | It will stay the same, it will not increase the resolution. |
| Definitions of resolution | Its the ability to distinguish between 2 seperate points |
| Whats the difference between higher resolution and low resolution | If the 2 points are viewed as 2 seperate points its called resolved, if the 2 points are viewed as blurred together, its called not resolved |
| What should the light need to do? | Hit a point to interfene with the light wave. |
| If the wavelength is 400nm (wavelength of light, used in light microscope), what is the smallest object you will be able to see | 200nm, half the wavelength of light |
| So what is the limit of wavelength | Half of the wavelength of the light source we are using. we won't be able to resolve things smaller than 200nm |
| What does the electron microscope have over the light microscope | It has a higher resolution |
| What is different in the source of the electron microscope | We use a beam of electrons, so its not really based on the limit of wavelength, however its still has a wavelength, its just really tiny |
| What is the wavelength in the electron microscope. | Only 1 nano metre |
| So what's the limit of wavelenght in an electron microscope | So we can see things down to 0.5 nano metres, we are going to see way more detail. |
| What would an increased magnification do to the resolution. | It will stay the same, it will not increase the resolution. |
| What is simple diffusion? | Net movement of molecules from high conc to low conc down the conc gradient |
| Where can diffusion happen | Through the cell membrane (phospholipid bi-layer) |
| How is simple diffusion limited though cell membranes | If it is too big it cant move into or out of the cell, also the phospholipid bi layer has hydrophobic parts (fatty acids) meaning that hydrophilic molecules cannot passthrough. |
| Why else might molecules not be able to pass through the cell membrane through simple diffusion | If it is a charged ion, it cannot move through. |
| So how do charged, polar or large particles pass through the hydrophobic bi layer? | Through facilitated diffusion. |
| Why can't h20 pass through the cell membrane | Because it has a dipole (charged) |
| So how can we let h20 pass through. | Through a protein channel |
| How can h2o pas through aquaporin | As it is protected by the hydrophobic parts of the bi layer |
| What do we do if we need to transport sodium ions and what not | We use transport proteins |
| What do transport proteins normally have | A gate so that it can open and close to let the ions through |
| What is the niche of the transport protein | They are always specific |
| What happens as the ions like Na+ travels through the transport protein. | It moves down the concentration gradient. |
| What is a carrier protien | It is a type of transport protein |
| What happens when a molecule binds with the carrier protein. | It will change shape to allow the molecule inside it to move through. It CARRIES across the molecule |
| What are tranport proteins and carrier proteins all examples of? | They are all examples of facillitated diffusion. meaning that the substances move down the concentration gradient, passive and not using ATP and they use transport proteins |