Difference between revisions of "Unit 2: The Cell"
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== Nucleus: Stores DNA for the cell. == | == Nucleus: Stores DNA for the cell. == | ||
| − | Eukaryotic cell: Has a nucleus. | + | Eukaryotic cell: Has a nucleus. |
Prokaryotic cell: No nucleus. | Prokaryotic cell: No nucleus. | ||
| + | |||
| + | '''OTHER DIFFERENCE BETWEEN EUKARYOTIC AND PROKARYOTIC...INNER MEMBRANES...SIZE''' | ||
Light microscope: uses lenses for focus. | Light microscope: uses lenses for focus. | ||
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Cell fractionation: Taking a cell apart to study it. | Cell fractionation: Taking a cell apart to study it. | ||
| − | Organelle: Organ for a cell. | + | '''CONSIDER LINKING THE ABOVE 3 TOPICS TO THE LAB TECHNIQUES''' |
| + | |||
| + | |||
| + | Organelle: Organ for a cell. '''NOT A GREAT DEFINITION''' | ||
| − | Mitochondrion: A organelle that makes ATP (a kind of chemical energy) for the cell. Has | + | Mitochondrion: A organelle that makes ATP (a kind of chemical energy) for the cell. Has its own DNA. |
| − | Chloroplast: organelle in plant cells. Used for photosynthesis. Has | + | Chloroplast: organelle in plant cells. Used for photosynthesis. Has its own DNA. |
| − | Rough endoplasmic reticulum: Organelle in a cell. Has lots of ribosomes on | + | Rough endoplasmic reticulum: Organelle in a cell. Has lots of ribosomes on its surface, so it appears rough when looking at it through a microscope. Creates secretory proteins and membranes. |
| − | Smooth endoplasmic reticulum: Organelle in a cell. Does not have ribosomes on | + | Smooth endoplasmic reticulum: Organelle in a cell. Does not have ribosomes on its surface, so it appears smooth when looking at it through a microscope. Used for metabolic processes. |
| − | Lysosome: Used to hydrolyse macromolecules. | + | Lysosome: Used to hydrolyse macromolecules. '''WHAT HAPPENS IF IT BREAKS OPEN INSIDE A CELL? IT HAS A DIFFERENT pH RIGHT?''' |
Vesicle: Transporter in the cell. | Vesicle: Transporter in the cell. | ||
| − | peroxisomes: Creates toxic hydrogen peroxide away from the rest of the cell. Fortunately it can also turn hydrogen peroxide back into water. | + | peroxisomes: Creates toxic hydrogen peroxide away from the rest of the cell. Fortunately it can also turn hydrogen peroxide back into water. |
Cytoskeleton: skeleton for the cell. Also used in cell motility when it interacts with motor proteins. | Cytoskeleton: skeleton for the cell. Also used in cell motility when it interacts with motor proteins. | ||
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Cell wall: Extracellular structure of plant cells. | Cell wall: Extracellular structure of plant cells. | ||
| − | Cytoplasm: Area of cell outside the nucleus. | + | Cytoplasm: Area of cell outside the nucleus. '''CYTOSOL?''' |
| − | Ribosome: Cellular components that carry out protein synthesis. | + | Ribosome: Cellular components that carry out protein synthesis. '''SOMETIMES CALLED AN ORGANELLES, SOMETIMES NOT...CONFUSING...''' |
Golgi apparatus: Ships and stores products of the endoplasmic reticulum out into the cell. | Golgi apparatus: Ships and stores products of the endoplasmic reticulum out into the cell. | ||
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Nucleolus: Mass of densely stained granules and fibres adjoining part of the chromatin. | Nucleolus: Mass of densely stained granules and fibres adjoining part of the chromatin. | ||
| + | |||
| + | '''CONSIDER INCLUDING A PICTURE FROM THE TEXTBOOK. MITOCHONDRIA, CHLOROPLASTS, GOLGI HAVE DISTINCTIVE STRUCTURES THAT YOU MAY BE ASKED TO IDENTIFY''' | ||
== Membrane structure and function == | == Membrane structure and function == | ||
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Concentration gradient: The gradient of the concentration of a substance. | Concentration gradient: The gradient of the concentration of a substance. | ||
| − | Integral proteins: Penetrate the hydrophobic interior of the lipid bilayer. | + | Integral proteins: Penetrate the hydrophobic interior of the lipid bilayer. '''USUALLY SPAN THE ENTIRE WIDTH OF THE MEMBRANE BUT SOME ONLY REACH HALFWAY THROUGH. TRANSPORT PROTEINS, FOR EXAMPLE, MUST SPAN THE ENTIRE WIDTH.''' |
Peripheral proteins: Not embedded in the lipid bilayer. loosely bound to the membrane. | Peripheral proteins: Not embedded in the lipid bilayer. loosely bound to the membrane. | ||
| − | Transport protein: Protein in the membrane that moves substances out of the cell. | + | Transport protein: Protein in the membrane that moves substances out of the cell. '''WHAT ARE THE DIFFERENT TYPES?''' |
Osmosis: When water moves down its concentration gradient. | Osmosis: When water moves down its concentration gradient. | ||
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Electrochemical gradient: A substance's concentration gradient plus some electrical forces control the movement of the substance. | Electrochemical gradient: A substance's concentration gradient plus some electrical forces control the movement of the substance. | ||
| − | Cotransport: A transport protein that uses the diffusion of one substance to power the active transport of another. | + | Cotransport: A transport protein that uses the diffusion of one substance to power the active transport of another. '''COTRANSPORT IS A MECHANISM, NOT A PHYSICAL PROTEIN. INCLUDE A PICTURE PLEASE!''' |
Exocytosis: The bulk transport of a large molecule from in the cell to out of the cell. A vesicle carries the molecule and then merges with the membrane. Releasing the molecule outside of the cell. | Exocytosis: The bulk transport of a large molecule from in the cell to out of the cell. A vesicle carries the molecule and then merges with the membrane. Releasing the molecule outside of the cell. | ||
| − | Endocytosis: When a pocket forms in the membrane to capture a substance and bring it back into the | + | Endocytosis: When a pocket forms in the membrane to capture a substance and bring it back into the cell by turning into a vesicle. There are 3 types of endocytosis. |
| − | |||
| − | |||
| − | |||
| − | |||
| − | Receptor mediated endocytosis: A type of endocytosis. Where a cell "drinks" a specific substance by using receptors by the substance, and then engulfing those receptors. | + | # Phagocytosis: A type of endocytosis. Where a cell "eats" a substance by engulfing it with pseudopodia. |
| + | # Pinocytosis: A type of endocytosis. Where a cell "drinks" substances by engulfing any substance it can capture. | ||
| + | # Receptor mediated endocytosis: A type of endocytosis. Where a cell "drinks" a specific substance by using receptors by the substance, and then engulfing those receptors. | ||
== Metabolism == | == Metabolism == | ||
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Second law of thermodynamics: Every energy transfer or transformation causes an increase of entropy in the universe. | Second law of thermodynamics: Every energy transfer or transformation causes an increase of entropy in the universe. | ||
| + | |||
| + | '''ENTROPY = ?''' | ||
Exergonic reaction: Reaction that releases energy into its surroundings. | Exergonic reaction: Reaction that releases energy into its surroundings. | ||
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Endergonic reaction: Reaction that absorbs energy from its surroundings. | Endergonic reaction: Reaction that absorbs energy from its surroundings. | ||
| − | Enzyme: Macromolecule that acts as a catalyst. | + | Enzyme: Macromolecule that acts as a catalyst. '''USUALLY A PROTEIN''' |
Substrate: The reactant an enzyme acts on. | Substrate: The reactant an enzyme acts on. | ||
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Competitive inhibitor: Reduces an enzyme's function by blocking its active site. | Competitive inhibitor: Reduces an enzyme's function by blocking its active site. | ||
| − | Non-competitive inhibitor: Reduces an enzyme's function by | + | Non-competitive inhibitor: Reduces an enzyme's function by binding to a site that is not an active site. |
Allosteric regulation: When a protein's function at one site is affected by a change at another site. | Allosteric regulation: When a protein's function at one site is affected by a change at another site. | ||
| − | Allosteric activation and inhibition: A protein oscillates between an active and inactive state. And activator molecule | + | Allosteric activation and inhibition: A protein oscillates between an active and inactive state. And activator molecule stabilizes the protein in its active state. Whereas an inhibitor molecule stabilizes the protein in its inactive state. |
Cooperative activation: When the binding of a substrate to a protein makes it easier for future substrates to bind to that protein. | Cooperative activation: When the binding of a substrate to a protein makes it easier for future substrates to bind to that protein. | ||
| + | |||
| + | '''CONSIDER PUTTING IN AN IMAGE FROM THE TEXTBOOK THAT ILLUSTRATES REGULATION, INHIBITION, AND ACTIVATION.''' | ||
== Cellular Respiration == | == Cellular Respiration == | ||
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Reducing agent: Substance that gives another an electron. | Reducing agent: Substance that gives another an electron. | ||
| − | + | Oxidating agent: Substance that receives an electron. | |
| + | |||
| + | '''AEROBIC RESPIRATION =''' | ||
| + | |||
| + | '''ANAEROBIC RESPIRATION =''' | ||
| − | Kreb's cycle: Cycle involved in cellular respiration. Also know as the citric acid cycle. Invented by someone with the last name Krebs. | + | '''PLEASE LIST THE STEPS OF CELLULAR RESPIRATION IN NUMBERED ORDER! INCLUDE STARTING MATERIAL AND THE RELEVANT PRODUCTS AND BYPRODUCTS. INCLUDE LOCATION.''' |
| + | |||
| + | Kreb's cycle: Cycle involved in cellular respiration. Also know as the citric acid cycle. Invented by someone with the last name Krebs. '''WHAT COMES IN, WHAT COMES OUT...''' | ||
[[File:Eb4ab5e6f97866cf9ee0b97dbd5782dd.jpg|thumb]] | [[File:Eb4ab5e6f97866cf9ee0b97dbd5782dd.jpg|thumb]] | ||
| − | Glycolysis: The breakdown of glucose by enzymes. Releases pyruvate. Happens in the cytoplasm. | + | Glycolysis: The breakdown of glucose by enzymes. Releases pyruvate. Happens in the cytoplasm. '''IS 1ST STEP IN BOTH AEROBIC AND ANAEROBIC RESPIRATION.''' |
| + | |||
| + | Pyruvate: Released by glycolysis. Can be broken into 6 NADH, 2 ATP, and 2 FADH. '''NOT TRUE....IT ISN'T BROKEN DOWN INTO THOSE MOLECULES. WHERE DID YOU READ THIS?''' | ||
| + | |||
| + | '''SUBSTRATE-LEVEL PHOSPHORYLATION =''' | ||
| + | |||
| + | Electron transport train: Used in cellular respiration. Turns 2 ATP, and 2 FADH into 36 ATP....'''YOU AREN'T TURNING 2 ATP INTO MORE ATP. PLEASE DESCRIBE THE PROTON GRADIENT HERE. WHAT IS THE FINAL ELECTRON ACCEPTOR?''' | ||
| + | |||
| + | '''CHEMIOSMOSIS =''' | ||
| − | + | '''OXIDATIVE PHOSPHORYLATION =''' | |
| − | + | '''ATP SYNTHASE =''' | |
| − | Fermentation: Used in anaerobic respiration. Produces lactic acid. | + | Fermentation: Used in anaerobic respiration. Produces lactic acid. '''...TWO TYPES OF FERMENTATION: 1. LACTIC ACID FERMENTATION 2. ALCOHOL FERMENTATION. INCLUDE AN IMAGE FROM THE PDF THAT SHOWS THE DIFFERENT BETWEEN THEM.''' |
Lactic acid: produced by fermentation. | Lactic acid: produced by fermentation. | ||
| + | |||
| + | |||
| + | '''TO BE HONEST, THE IMAGE TO THE RIGHT SEEMS WRONG TO ME. PYRUVATE AND KREB'S CYCLE ARE SWITCHED. PLEASE INCLUDE YOUR IMAGE INSTEAD.''' | ||
== Photosynthesis == | == Photosynthesis == | ||
| − | Photosynthesis: Synthesis using light. | + | Photosynthesis: Synthesis using light. '''OCCURS IN WHAT ORGANISMS?''' |
Stroma: Dense fluid inside chloroplast. | Stroma: Dense fluid inside chloroplast. | ||
| − | Pigment: Substance that absorbs visible light. | + | Pigment: Substance that absorbs visible light. '''INCLUDE EXAMPLES OF PIGMENTS WE DISCUSSED''' |
| + | |||
| + | Spectrophotometry: Measurement of the reflection or transmission properties of a material related to its wavelength '''LINK TO LAB TECHNIQUES''' | ||
| + | |||
| + | Absorption spectrum: A graph plotting a pigment’s light absorption compared with its wavelength '''INCLUDE A PICTURE FROM THE PDF OF DIFFERENT PIGMENTS AND THEIR ABSORPTION SPECTRUM''' | ||
| + | |||
| + | '''PLEASE LIST THE STEPS OF PHOTOSYNTHESIS IN NUMBERED ORDER! INCLUDE STARTING MATERIAL AND THE RELEVANT PRODUCTS AND BYPRODUCTS. INCLUDE LOCATION AND PICTURES''' | ||
| + | |||
| + | Light reactions: Process that occurs in chloroplasts. Takes in light and releases o2. '''WHERE IN CHLOROPLAST? OTHER NAMES? PHOTOSYSTEMS AND IN WHAT ORDER? IS ATP PRODUCED?''' | ||
| + | |||
| + | Calvin cycle: Process that occurs in chloroplasts. Takes in co2 and produces sugar. '''WHERE IN CHLOROPLAST? OTHER NAMES? PRODUCT? HOW MANY MOLECULES OF CO2 ARE NEEDED FOR 1 GLUCOSE MOLECULE? WHAT IS THE END RESULT OF 1 TURN OF THE CYCLE?''' | ||
| + | |||
| + | |||
| + | '''CONNECTION BETWEEN WATER LOSS AND PHOTOSYNTHESIS (INCLUDE STOMATA IN YOUR ANSWER)''' | ||
| − | + | '''C3 PLANTS =''' | |
| − | + | '''IF WATER LOSS IS TOO GREAT AND STOMATA HAVE TO CLOSE DURING THE DAY, WHAT HAPPENS IN CALVIN CYCLE?''' | |
| − | + | '''PHOTORESPIRATION =''' | |
| − | + | '''2 MECHANISMS PLANTS HAVE EVOLVED TO DEAL WITH PHOTORESPIRATION?''' | |
Revision as of 11:27, 22 December 2020
Nucleus: Stores DNA for the cell.
Eukaryotic cell: Has a nucleus.
Prokaryotic cell: No nucleus.
OTHER DIFFERENCE BETWEEN EUKARYOTIC AND PROKARYOTIC...INNER MEMBRANES...SIZE
Light microscope: uses lenses for focus.
Electron microscope: Creates beam of electrons for focus. It can be scanning, or transmission.
Cell fractionation: Taking a cell apart to study it.
CONSIDER LINKING THE ABOVE 3 TOPICS TO THE LAB TECHNIQUES
Organelle: Organ for a cell. NOT A GREAT DEFINITION
Mitochondrion: A organelle that makes ATP (a kind of chemical energy) for the cell. Has its own DNA.
Chloroplast: organelle in plant cells. Used for photosynthesis. Has its own DNA.
Rough endoplasmic reticulum: Organelle in a cell. Has lots of ribosomes on its surface, so it appears rough when looking at it through a microscope. Creates secretory proteins and membranes.
Smooth endoplasmic reticulum: Organelle in a cell. Does not have ribosomes on its surface, so it appears smooth when looking at it through a microscope. Used for metabolic processes.
Lysosome: Used to hydrolyse macromolecules. WHAT HAPPENS IF IT BREAKS OPEN INSIDE A CELL? IT HAS A DIFFERENT pH RIGHT?
Vesicle: Transporter in the cell.
peroxisomes: Creates toxic hydrogen peroxide away from the rest of the cell. Fortunately it can also turn hydrogen peroxide back into water.
Cytoskeleton: skeleton for the cell. Also used in cell motility when it interacts with motor proteins.
Cell wall: Extracellular structure of plant cells.
Cytoplasm: Area of cell outside the nucleus. CYTOSOL?
Ribosome: Cellular components that carry out protein synthesis. SOMETIMES CALLED AN ORGANELLES, SOMETIMES NOT...CONFUSING...
Golgi apparatus: Ships and stores products of the endoplasmic reticulum out into the cell.
Cristae: Fold in mitochondria
Nucleolus: Mass of densely stained granules and fibres adjoining part of the chromatin.
CONSIDER INCLUDING A PICTURE FROM THE TEXTBOOK. MITOCHONDRIA, CHLOROPLASTS, GOLGI HAVE DISTINCTIVE STRUCTURES THAT YOU MAY BE ASKED TO IDENTIFY
Membrane structure and function
Diffusion: Substances move to areas with less concentration of itself.
Concentration gradient: The gradient of the concentration of a substance.
Integral proteins: Penetrate the hydrophobic interior of the lipid bilayer. USUALLY SPAN THE ENTIRE WIDTH OF THE MEMBRANE BUT SOME ONLY REACH HALFWAY THROUGH. TRANSPORT PROTEINS, FOR EXAMPLE, MUST SPAN THE ENTIRE WIDTH.
Peripheral proteins: Not embedded in the lipid bilayer. loosely bound to the membrane.
Transport protein: Protein in the membrane that moves substances out of the cell. WHAT ARE THE DIFFERENT TYPES?
Osmosis: When water moves down its concentration gradient.
Osmoregulation: When a cell regulates water flowing in and out of itself.
Facilitated diffusion: when a substance is assisted in moving down its concentration gradient.
Active transport: When a substance is moved against its concentration gradient.
Electrochemical gradient: A substance's concentration gradient plus some electrical forces control the movement of the substance.
Cotransport: A transport protein that uses the diffusion of one substance to power the active transport of another. COTRANSPORT IS A MECHANISM, NOT A PHYSICAL PROTEIN. INCLUDE A PICTURE PLEASE!
Exocytosis: The bulk transport of a large molecule from in the cell to out of the cell. A vesicle carries the molecule and then merges with the membrane. Releasing the molecule outside of the cell.
Endocytosis: When a pocket forms in the membrane to capture a substance and bring it back into the cell by turning into a vesicle. There are 3 types of endocytosis.
- Phagocytosis: A type of endocytosis. Where a cell "eats" a substance by engulfing it with pseudopodia.
- Pinocytosis: A type of endocytosis. Where a cell "drinks" substances by engulfing any substance it can capture.
- Receptor mediated endocytosis: A type of endocytosis. Where a cell "drinks" a specific substance by using receptors by the substance, and then engulfing those receptors.
Metabolism
Metabolic pathway: A series of reactions that turn a starting molecule into an end product.
Catabolic pathway: A metabolic pathway that releases energy by turning a starting molecule into a simpler one.
Anabolic pathway: A metabolic pathway that consumes energy to turn a starting molecule into a more complex one.
Kinetic energy: Energy associated with the relative movement of objects.
Thermal energy: Energy relating to the random movement of atoms and molecules.
Heat: Thermal energy in transport from one object to another.
Potential energy: The potential for energy that matter posses because of its location or structure.
Chemical energy: Type of potential energy that can be released in a chemical reaction.
First law of thermodynamics: Energy can never be created or destroyed.
Second law of thermodynamics: Every energy transfer or transformation causes an increase of entropy in the universe.
ENTROPY = ?
Exergonic reaction: Reaction that releases energy into its surroundings.
Endergonic reaction: Reaction that absorbs energy from its surroundings.
Enzyme: Macromolecule that acts as a catalyst. USUALLY A PROTEIN
Substrate: The reactant an enzyme acts on.
Active site: Site on an enzyme that a substrate binds with.
Competitive inhibitor: Reduces an enzyme's function by blocking its active site.
Non-competitive inhibitor: Reduces an enzyme's function by binding to a site that is not an active site.
Allosteric regulation: When a protein's function at one site is affected by a change at another site.
Allosteric activation and inhibition: A protein oscillates between an active and inactive state. And activator molecule stabilizes the protein in its active state. Whereas an inhibitor molecule stabilizes the protein in its inactive state.
Cooperative activation: When the binding of a substrate to a protein makes it easier for future substrates to bind to that protein.
CONSIDER PUTTING IN AN IMAGE FROM THE TEXTBOOK THAT ILLUSTRATES REGULATION, INHIBITION, AND ACTIVATION.
Cellular Respiration
Oxidation: Loss of electrons.
Reduction: Gaining electrons. Yes, really: gaining.
Reducing agent: Substance that gives another an electron.
Oxidating agent: Substance that receives an electron.
AEROBIC RESPIRATION =
ANAEROBIC RESPIRATION =
PLEASE LIST THE STEPS OF CELLULAR RESPIRATION IN NUMBERED ORDER! INCLUDE STARTING MATERIAL AND THE RELEVANT PRODUCTS AND BYPRODUCTS. INCLUDE LOCATION.
Kreb's cycle: Cycle involved in cellular respiration. Also know as the citric acid cycle. Invented by someone with the last name Krebs. WHAT COMES IN, WHAT COMES OUT...
Glycolysis: The breakdown of glucose by enzymes. Releases pyruvate. Happens in the cytoplasm. IS 1ST STEP IN BOTH AEROBIC AND ANAEROBIC RESPIRATION.
Pyruvate: Released by glycolysis. Can be broken into 6 NADH, 2 ATP, and 2 FADH. NOT TRUE....IT ISN'T BROKEN DOWN INTO THOSE MOLECULES. WHERE DID YOU READ THIS?
SUBSTRATE-LEVEL PHOSPHORYLATION =
Electron transport train: Used in cellular respiration. Turns 2 ATP, and 2 FADH into 36 ATP....YOU AREN'T TURNING 2 ATP INTO MORE ATP. PLEASE DESCRIBE THE PROTON GRADIENT HERE. WHAT IS THE FINAL ELECTRON ACCEPTOR?
CHEMIOSMOSIS =
OXIDATIVE PHOSPHORYLATION =
ATP SYNTHASE =
Fermentation: Used in anaerobic respiration. Produces lactic acid. ...TWO TYPES OF FERMENTATION: 1. LACTIC ACID FERMENTATION 2. ALCOHOL FERMENTATION. INCLUDE AN IMAGE FROM THE PDF THAT SHOWS THE DIFFERENT BETWEEN THEM.
Lactic acid: produced by fermentation.
TO BE HONEST, THE IMAGE TO THE RIGHT SEEMS WRONG TO ME. PYRUVATE AND KREB'S CYCLE ARE SWITCHED. PLEASE INCLUDE YOUR IMAGE INSTEAD.
Photosynthesis
Photosynthesis: Synthesis using light. OCCURS IN WHAT ORGANISMS?
Stroma: Dense fluid inside chloroplast.
Pigment: Substance that absorbs visible light. INCLUDE EXAMPLES OF PIGMENTS WE DISCUSSED
Spectrophotometry: Measurement of the reflection or transmission properties of a material related to its wavelength LINK TO LAB TECHNIQUES
Absorption spectrum: A graph plotting a pigment’s light absorption compared with its wavelength INCLUDE A PICTURE FROM THE PDF OF DIFFERENT PIGMENTS AND THEIR ABSORPTION SPECTRUM
PLEASE LIST THE STEPS OF PHOTOSYNTHESIS IN NUMBERED ORDER! INCLUDE STARTING MATERIAL AND THE RELEVANT PRODUCTS AND BYPRODUCTS. INCLUDE LOCATION AND PICTURES
Light reactions: Process that occurs in chloroplasts. Takes in light and releases o2. WHERE IN CHLOROPLAST? OTHER NAMES? PHOTOSYSTEMS AND IN WHAT ORDER? IS ATP PRODUCED?
Calvin cycle: Process that occurs in chloroplasts. Takes in co2 and produces sugar. WHERE IN CHLOROPLAST? OTHER NAMES? PRODUCT? HOW MANY MOLECULES OF CO2 ARE NEEDED FOR 1 GLUCOSE MOLECULE? WHAT IS THE END RESULT OF 1 TURN OF THE CYCLE?
CONNECTION BETWEEN WATER LOSS AND PHOTOSYNTHESIS (INCLUDE STOMATA IN YOUR ANSWER)
C3 PLANTS =
IF WATER LOSS IS TOO GREAT AND STOMATA HAVE TO CLOSE DURING THE DAY, WHAT HAPPENS IN CALVIN CYCLE?
PHOTORESPIRATION =
2 MECHANISMS PLANTS HAVE EVOLVED TO DEAL WITH PHOTORESPIRATION?