U1 U2 U3 Flashcards
What are the 13 General Guidelines?
- No Horseplay.2. Only perform experiments that are authorized by your teacher. Follow all instructions. Read all instructions before beginning work and ask for help if you don’t understand.3. Don’t waste materials by using more than instructed. Ask What are the teacher before, if you think you need more.4. When you enter the room, never touch any equipment or other lab materials until you are instructed to.5. No food or gum on lab days. Water allowed away from lab and only with washed hands.6. Keep all work areas clean and tidy, other materials under tables, push in chairs.7. Know where all the safety equipment is, where the fire alarms are and exits are located in relation to the classroom and know what to do in case of an emergency.8. Be aware of surroundings and tell teacher if anything is unsafe.9. Dispose of all waste properly10. Only use lab equipment directed by your teacher, read all labels and instructions provided before using lab equipment.11. Wash hands after all lab activities, hands away from face, mouth and belongings.12. Do not wander, distract other students, or transport lab equipment around the classroom(unless instructed).13. carry tips away and pointed down and grasp by handles when using sharp tools. Always cut away from your body and belongings
What are the 4 Clothing Guidelines?
- Goggles and gloves must be worn any time chemicals, heat or glassware are used.2. No loose items (hair, clothes, jewelry).3. Close toed shoes.4. Make sure you are weaaring the correct clothes when it is lab day.
What are the 9 Dissection Safety Guidelines?
- Treat all specimens with respect and care.2. Handle all instruments with extreme care.3. Always cut away from your body and away from others.4. Avoid contact with preservative chemicals.5. Never remove preserved specimens or tissues from the lab.6. Store specimens between lab periods as directed by your instructor.7. Dispose of dissected materials in the appropriate waste container as indicated by your instructor.8. Clean up your work area, wash and dry dissecting tools and return all supplies to the correct place.9. Wash your hands thoroughly with soap and water after cleanup.
What are the 2 Accidents and Injuries Guidelines?
1.Report all accidents and injuries immediately. If a chemical gets in the eye, wash it out.2. All chemicals in the laboratory should be considered dangerous, don’t touch,taste, or smell unless instructed.
What are the 4 Glassware and Equipment Guidelines?
- Don’t touch glass or throw it in the trash can. Tell the teacher imminently when glass breaks.2. Don’t use chipped or cracked glass and don’t place hot glass in cold water (or Vise Versa).3. Grasp plug, not cord, when unplugging charger.4. Report any damaged electrical equipment to your teacher immediately. Don’t used damaged or wet electrical equipment
What are the 2 Heating Substances Guidelines
- Never leave a hot plate unattended. Turn off when not in use.2. Never look into a container that is being heated. Never point the open end of a heated test tube at yourself or others.
What are the Guideline headlines and how many within them?
- General Guidelines 132. Dissection Safety Guidelines 93. Heating Substances Guidelines 24. Glassware and Equipment Guidelines 45. Clothing Guidelines 46. Accidents and Injuries 2
What does Biology mean?
Study of Living Things
What does Biology mean?
Study of Living Things
What are some examples of Biology?
Human BodyMolecularMicroorganismsPlants and Animals
What are the Characteristics of Living Things?
- Organized in one or more cells- Universal Genetic code(DNA)- Respond to Environment(Stimuli)- Reproduce- Grow and Develop- Maintaining Homeostasis(Regulate, Stability)- Obtain and Use Energy- Evolve(as group, over time)
What is the Scientific Method Steps?
Question Research Hypothesis ——- Become Background Troubleshoot ————- Test within Experiment info l Procedure Working? l ———————–no yes l Analyze Data l Conclusion l align with hypo not align ————- Comm Results
Goggles
protects eyes
Bunsen Burner
used to heat substances
Graduated Cylinder
accurately measures liquid volumes
Spot Plate
a flat plate with multiple “wells” used as small test tubes
Pipet Bulb
used to pull liquid up into a pipet
Stirring Rod
used for stirring
Evaporating Dish
liquids are heated over a flame so that they evaporate, leaving a solid residue
Crucible Tongs
to hold hot crucibles
Forceps
used to pick up or hold small items
Watch Glass
to hold solids while being weighed, or as a cover for a beaker
Beaker
used to hold liquids
Thermometer
measures temperature
Crucible and Cover
used to hold small amounts of chemicals during heating at high temperatures
Test Tube Clamp
clamp used to hold hot test-tube
Buret
dispensing and transferring known volumes of fluids
Balance
an instrument for determining weight
Dropper Pipet or Disposable Pipet
for drawing in a liquid and expelling it in drops
Volumetric Flask
for making up solutions to a known volume
Funnel
for pouring liquid or other substance through a small opening
Utility Clamp
used to hold laboratory glassware
Mortar and Pestle
used to grind up materials
Volumetric Pipet
measures small amounts of liquids accurately
Striker
used to light bunsen burner
Rubber Stopper
used to cover ends of test tubes and flasks
Spatula
small scoop used to transfer powder and crystal chemicals
Wire Gauze
used to support a container (such as a beaker or flask) during heating
Test Tube Rack
holds 5-6 test-tubes in a row
Wash Bottle
used to rinse various pieces of laboratory glassware used to rinse various pieces of laboratory glassware
Ring Stand
holds funnels, wire gauze above table
Erlenmeyer Flask
used to hold liquids, has narrow neck to prevent splashes
Ring Clamp
used with ring stand to hold a glass container
Clay Triangle
used to hold a crucible while the crucible is heated
Test Tube
open tube used to hold liquids
Weighing Paper
used for weighing and transferring powers and crystals
Filter Paper
special paper used to separate solids from liquids
Fume Hood
used to prevent a person from exposure to hazardous fumes from chemicals
Hot Plate/ Stir Plate
used to heat and stir substances
What are the expectations and norms as listed in the syllabus?
- Be in your assigned seat, ready to begin when the class period starts.2. Always bring all required materials with you to class, and put away all non-class materials before class begins.3. Show respect to your classmates, teacher, classroom, and yourself, in both your words and actions.4. Do not disrupt the classroom learning environment for your fellow students and teacher. Follow your teacher’s procedures to ask questions or ask for help (ex. raising your hand and waiting to be called on).5. Cell phones, computers, and other electronic devices must be put away in a location designated by the teacher, unless specifically directed otherwise for a class activity.6. If an issue arises or you have a question, communicate with your teacher about it as soon as possible.
What is the lasa honor code
On my honor, I have neither given nor received unauthorized aid on my work, nor do I tolerate academic dishonesty in others.
What is a hypothesis?
A testable explanation or prediction based on the observation and the scientist’s prior knowledge
What is a null hypothesis?
A prediction that there is no relationship between two variables.
What is an independent variable?
The factor or condition being changed“the cause”X-axis
What is a dependent variable?
The factor or condition being measured“the effect”Y-axis
What is a control variable?
A factor or condition that is keptconstant throughout the experiment
What is a control group?
This group experiences the sameconditions as the experimental group,except for the single independentvariable being studied
What is a controlled experiment?
done in lab
What is a natural experiment?
observing andanalyzing something happeningnaturally, out of control of the scientist
What is quantitative data?
Based on numbers
What is Qualitative data?
Based on Observation
What is an atom?
the basic unit of matter.
What is an element?
a pure substancethat consists of one type ofatom.
What is an atom composed of?
Atoms are composed of threesubatomic particles:
What is a Proton?
Positively charged subatomic particle, found inthe nucleus.
What is a Neutron?
Subatomic particle with no charge, found inthe nucleus.
What is an electron?
Negatively charged subatomic particle, foundoutside of the nucleus.
What are the first 3 layers of electron shells made of?
1st Orbital: Maximum 2 electrons2nd Orbital: Maximum 8 electrons3rd Orbital: Maximum 18 electrons
What is an atomic number?
the number of protons in the atom.
What is a mass number?
the total number of protons and neutrons inthe nucleus of an atom.
What is atomic weight?
the weighted average of the masses of anelement’s isotopes.
What is an isotope?
Atoms off the same element that differ in the numbers of neutrons they contain. Identified by mass number.
What is a valence shell?
the outer orbital/electron shell.
What is a cell?
basic unit of life
What is a compound?
a substance formed by the chemical combination of two or more elements in definite proportions.
What is a molecule?
made when two or more atoms are chemically bonded together?
What are the two types of chemical bonds?
Ionic and Covalent
What are ionic bonds?
Chemical bond formed when one or moreelectrons are transferred from one atom to another.
What is an ion?
An atom that either gains electrons or loses electrons.As such, it is either positively or negatively charged.
What are covalent bonds ?
Chemical bond formed when the electronsare shared between atoms.
What do carbons four valence electrons allow them to do?
bond with many otheratoms. As such, chains of carbon often formthe backbone of macromolecules.
What are macromolecules?
Macromolecules are largemolecules made frommany smaller molecules.
What are Monomers and Polymers?
Monomers: the small units.* Polymers: the large units.
What is polarity in a hydrogen molecule?
a water moleculeis polar because there isan uneven distribution ofelectrons between thehydrogen atoms andoxygen atoms. Thenegative pole is near theoxygen atom and thepositive pole is near thehydrogen atoms
What are Intramolecular forces?
forces that holdatoms together withina molecule.
What are Intermolecular forces?
forces that existbetween molecules.
what is a hydrogen bond?
attraction between ahydrogen atom andanother atom.
What is cohesion and adhesion?
attraction of molecules of the same substance.attraction between molecules of different substances.
What is Capillary Action?
tendency of water to rise in a thin tube.
What is a mixture?
a material composed of two or more elements orcompounds that are physically mixed together but not chemicallycombined.
What is a suspension?
mixture of water and nondissolved material
What is a solution?
type of mixture in which all components are evenlydistributed
What are solutes and solvents?
Solute: substance that is dissolved in solution. Ex: sugar,saltSolvent: dissolving substance in a solution. Ex: water
What is hydrophobic?
nonpolarmolecules that repel watermolecules. “Water fearing”
What is hydrophilic?
molecules formingionic or a hydrogen bond withwater molecules. “Waterloving”
What is surface tension?
The surface becomes stronger because they exert more force horizontally when they cant exert it up(happens to water)
What is Dehydration Synthesis?
A chemical reaction that builds upmolecules by losing watermolecules.
What is hydrolysis?
The process of splitting acompound into fragments with theaddition of water; a kind of reactionthat is used to break down polymersinto simpler units, e.g. starch intoglucose.
What is Anabolism?
The process ofcreating large molecules fromsmaller molecules, utilizingenergy.
What is Catabolism
The process ofbreaking large molecules downinto smaller molecules,releasing energy.
How many types of biomolecule classes are there and what are they?
There are fourtypes:* Carbohydrates (sugars)* Carbon, Hydrogen, and Oxygen* Lipids (fats)* Carbon, Hydrogen, and Oxygen* Proteins* Carbon, Hydrogen, Oxygen, andNitrogen* Nucleic Acids (DNA/RNA)* Carbon, Hydrogen, Oxygen,Nitrogen, and Phosphorous
What is a carbohydrate and functions?
Organic compounds made of carbon,hydrogen and oxygen atoms. Functionsinclude:■ Most carbohydrates are brokendown into glucose which istaken up by cells to make ATP● Chemical formula forglucose is C6H12O6ATP uses phosphate in a process of catabolism when giving energy.■ ATP is used as a source ofenergy for a variety ofmetabolic processesmono,di,polysaccharides?!?!?!?!?
What is a Monosaccharides?
building block* Glucose: one of the body’s primary energy sources* Fructose:naturally occuring sugar common infruits
What is a Disaccharides?
Disaccharides: 2 monosaccharides combines* Sucrose (glucose + fructose), table sugar* Lactose (glucose + galactose), milk sugar
What is a Polysaccharides?
Polysaccharides: 2+ monosaccharides* Starch (chain of glucose); Used byplants to store sugar* Glycogen (chain of glucose); Used byanimals to store sugar* Cellulose (chain of glucose); Tough andflexible fiber that gives plants strengthand flexibility
+What are Lipids and Functions?
Organic compounds made mostly fromcarbon and hydrogen atoms and aregenerally not soluble in water.Non-polar and hydrophillicFunctions:* Store energy* Biological membranes* Steroids, such as hormones,act as chemical messengers* Waterproof coverings (plants)
What is a saturated fatty acid?
A fattyacid that contains carbonsonly joined by single bonds.* Maximum number of hydrogens* Examples: Fats, waxes
What is an unsaturated fatty acid?
A fatty acid that contains atleast one double bondbetween carbon atoms.* Fewer hydrogens* Examples: cooking oils
What are trans fats?
Trans Fats are unsaturated fatswhich are uncommon in nature, butcan be created artificially (chemicallyaltered vegetable oil)..Trans fats are edible,but have been known toraise the risk ofcoronary heart disease.Has been found that people that consume transfats experience a significant increase in LDL(bad) cholesterol) without a corresponding rise inHDL (good cholesterol).
What are proteins and functions?
Macromolecules that contain nitrogen as well as carbon,hydrogen, and oxygen.Functions:* Control the rate of reactions (enzymes)* Regulate cell processes (transport substances, help fight diseases)* Form cellular structures* The building block (monomer) of a protein is the amino acid* Amino acids: Organic compounds with an amino group (-NH2) onone end and a carboxyl group (-COOH) on the other end.* Multiple amino acids linked together (via covalent peptide bonds) formpolypeptides (polymer).* A protein is a function molecule built from one or morepolypeptides.
How many types of amino acids are there and what must they contain?
There are over 20 differentkinds of amino acids. Allamino acids consist of:* Central carbon atom* Carboxyl group* Amino group* Hydrogen atom* Variable “R” group
Whats the difference in the different types of amino acids?What are R groups?
The only difference in the 20kinds of amino acids is the “R”group.* R groups vary in size, can be polar or nonpolar,acid or basic* The shape and function of a protein is determinedby the “R” group.
How are amino acids assembled?
Amino acids are assembled intopolypeptide chains according toinstructions coded in DNA.Scientists describe protein ashaving four levels of structurewhich enables a protein tocarry out a specific job. .
What is the first level of folding for proteins?
Primary Structure: The sequence ofamino acids.Sequence is defined by genes withinmolecules of DNA.
What is the second level of folding for proteins?
Secondary Structure: Coilsand folding of the aminoacid chain.* Hydrogen bonding between aminoacids can form helix or pleated sheet.
What is the third level of folding for proteins?
Tertiary Structure: The three-dimensional shape of theprotein that is stabilized by interactions betweenR-groups(side chains).
What is the fourth level of folding for proteins?
Quaternary Structure: Association between two or moredifferent polypeptide chains (protein subunits)found inonly some proteins.
What is the Secondary Structure: Alpha Helix?
Keratin in hair and the subunits ofhemoglobin have a helix secondarystructure.Coiled structure due to hydrogenbonding between Oxygens ofcarboxylic acid group of one aminoacid and hydrogens of the aminogroup of another amino acid.
What is the Secondary Structure: Beta Pleated Sheet?
Silk, is a natural protein fiber, thatconsists of polypeptide chains thatrepeat back and forth uponthemselves. Hydrogen bonds holdadjacent segments of thepolypeptide together.* Where does silk come from?* From the cocoons of the larvae ofmoth caterpillars.
What is a nucleic acid?
Macromolecules containing hydrogen, oxygen,nitrogen, carbon, and phosphorus.* Monomer: nucleotide* Polymer: nucleic acidsNucleotides have three parts:* A 5-carbon sugar* A phosphate group* A Nitrogenous baseNucleoside has the same parts except no nitrogenous baseNucleic acids store and transmit hereditary or geneticinformation.* Examples: DNA, RNANitrogenous Base DNA: A,C,G,TRNA: A,C,G,UThe sugars and phosphates lie onthe outside of the helix, formingthe backbone of the DNA○ This portion of the moleculeis sometimes calledthe sugar-phosphate backbone.● The two strands of the helix run inopposite directions○ Meaning that the 5′ end ofone strand is paired up withthe 3′ end of its matchingstrand.○ This is referred toas antiparallel orientationand is important for thecopying of DNA.
What are the Essential and non essential amino acids?
Essential amino acids(9) you cant produce them, you must get from natureNon-Essential amino acids(11) you can produce them using essential amino acids
What are ex of physical and chemical changes and what is equilibrium/homeostasis?
2H2+O2 —> 2H2O H2O(l) —> H2O(g)Chemical PhysicalEquilibrium is when a reaction goes both ways( <—->)
Chemical vs Physical Reaction?
Chemical reactions involve the breaking and/or forming of bonds. This is DIFFERENT from a physical change, like something changing state or being cut into pieces. One common misconception is that something melting/boiling/freezing/etc is a chemical reaction. It is NOT. In order for something to be a chemical change/reaction, the chemical itself must be changing in some way. So for example, if you have an ice cube that melts, it is still water. If you boil water, it is STILL H2O, it just happens to now be a gas versus a liquid. So, those would both be physical changes. If you were to take water and break it apart into hydrogen and oxygen gas, though, that would then be a chemical change, because it is no longer H2O.
What is a coefficient in terms of a reaction?
When looking at a chemical reaction, the number in front of a substance is called the coefficient, and it tells you how many of that particular substance is needed for the reaction to occur. In this example with water, you need 2 molecules of H2 and only 1 molecule of O2, in order to form 2 molecules of H2O.
What are the letters to know the states of matter?
Some chemical reactions will have a letter in parentheses after each substance. The letter tells you what state of matter that substance is in. For example, if this reaction said O2 (g), that would tell you that it is oxygen gas specifically. “g” for gas, “l” for liquid, “s” for solid, “aq” for aqueous (dissolved)
Exothermic Reaction?
An exothermic reaction releases energy from the system in the form of heat.. Exothermic reactions can happen on their own (“spontaneously”)- The reaction is colder than surroundings
Endothermic Reaction?
An endothermic reaction absorbs energy from its surrounding in the form of heat.endothermic reaction cannot happen unless there is an input of energy.- The reaction is hotter than surroundings
Know the potential energy diagram?(how do you determine if its endo or exothermic based off the graph?)
We call these types of graphs “potential energy diagrams”. You can determine if a reaction is endothermic or exothermic by looking at the energy level of the products versus the reactants.
Explain the example reaction of the formation of water?
2H2(g)+O2 —> 2H2O(g) + Energythis reaction releases energy, and happens spontaneouslyin order to reverse this reaction, you have to input energy, it doesn’t occur on its own!EX. You have to run an electric current through water to decompose it into hydrogen and oxygen gas!
What is activation energy(Ea)? and their relation to exo/endothermic reactions?
Energy needed to start a reactionIn the case of an exothermic reaction, the reactants are at a higher energy level as compared to the products, as shown below in the energy diagrams. In other words, the products are more stable than the reactants. Overall ΔH for the reaction is negative, i.e., energy is released in the form of heat.In the case of an endothermic reaction, the reactants are at a lower energy level compared to the products—as shown in the energy diagram below. In other words, the products are less stable than the reactants. Since we are forcing the reaction in the forward direction towards more unstable entities, overall ΔH for the reaction is positive, i.e., energy is absorbed from the surroundings.
What is a catalyst?
speeds up chemical reaction by lowering activation energyReusable!
What is an enzyme?
a biological catalyst (protein!)Reusable!
what does the enzyme actually do to the substrate to make the activation energy lower?
The answer depends on the enzyme. Some enzymes speed up chemical reactions by bringing two substrates together in the right orientation. Others create an environment inside the active site that’s favorable to the reaction (for instance, one that’s slightly acidic or non-polar). The enzyme-substrate complex can also lower activation energy by bending substrate molecules in a way that facilitates bond-breaking, helping to reach the transition state.
Factors that may affect the active site and enzyme function include:
Temperature. A higher temperature generally makes for higher rates of reaction, enzyme-catalyzed or otherwise. However, either increasing or decreasing the temperature outside of a tolerable range can affect chemical bonds in the active site, making them less well-suited to bind substrates. Very high temperatures (for animal enzymes, above 40∘C or 104∘F) may cause an enzyme to denature, losing its shape and activity.pH. pH can also affect enzyme function. Active site amino acid residues often have acidic or basic properties that are important for catalysis. Changes in pH can affect these residues and make it hard for substrates to bind. Enzymes work best within a certain pH range, and, as with temperature, extreme pH values (acidic or basic) can make enzymes denature.
What is Denature?
Breaking of enzyme down
What are substrates?
Reactants
What is the slowest known biological reaction without an enzyme catalyst(what is that reaction with a catalyst)?
Protein phosphatase enzyme, helps regulate communication between human cells, including communication related to health/diseases1 trillion years w/ out10 milliseconds with
Would there be life w/ out catalysts?
no
What are enzymes structure and what are their names usually derived from?
Pictures shows TERTIARY-remember enzymes are proteins, they will have tertiary structure. Some quaternary. Enzyme names are usually derived from the reaction it catalyzes.
What is specificity in an enzyme?
Shape determines function - an enzyme is specific for a substrate!They only act on a specific substrate.
Understand the difference between Enzyme/Substrate complex and Enzyme/Products complex?
Enzyme changes shape slightly as substrate binds.
What is a pH level?
The pH level measures how acidic or basic a solution is, by measuring the concentration of H+ ions that are present!
Acid and Base(pH)?
AcidCompound that releases H+ ions in a solutEX -> HCl (hydrochloric acid), H2SO4 (sulphuric acid)BaseCompound that releases OH- ions in a solutionEX -> sodium hydroxide (NaOH), calcium hydroxide (Ca(OH)2)
What are properties of more acidic and more basic/alkaline pH’s?
More AcidicLower pHMore H+ ionsLess OH- ionsMore Basic/AlkalineHigher pHLess H+ ionsMore OH- ions
What happens to acids and bases in an aqueous solution?
(a) In aqueous (watery) solution, an acid dissociates into hydrogen ions (H+) and anions(negative). Every molecule of a strong acid dissociates, producing a high concentration of H+. (b) In aqueous solution, a base dissociates into hydroxyl ions (OH–) and cations(Positive). Every molecule of a strong base dissociates, producing a high concentration of OH–.
What is a buffer?
A buffer is a weak acid (only some of the substance dissociates completely into H+ ions) or base (only some of the substance dissociates completely into OH- ions) that can react with strong acids or bases to prevent sharp, sudden changes in pH.
What is an example of a buffer(hint:blood)?
Blood contains large amounts of carbonic acid (weak acid) & bicarbonate (weak base). Together they help maintain blood pH at 7.4. If blood pH falls below 6.8 or rises above 7.8, one can become sick or die. The bicarbonate neutralizes excess acids in the blood while the carbonic acid neutralizes excess bases.
What is the lock and key model?
Lock-and-Key Model. In this model, we describe the substrate as a “key” that fits intothe enzyme’s “lock”, or its active site. Since the active site is the exact shape thatmatches up with the substrate’s shape in order for it to fit, it’s similar to how a lock isthe same shape as a key, allowing it to unlock if only that specific key is used on it.
What is the induced fit model?
This model was suggested in 1958, by Daniel Koshland. Itsuggests that the correct substrate is able to induce the active site to change shapeinto the proper alignment that enables the enzyme to perform its catalytic function. So,an active site on an enzyme is flexible and continues to change until the substrate isbound in the active site, at which point the final shape and charge is determined as theactive site conforms to the substrate’s shape, allowing the reaction to be catalyzed.
What is an inhibator?
An inhibitor is something that prevents an enzyme fromdoing its job to catalyze a reaction.
What does a light microscope do?
Uses lenses to magnify the image of an object by focusing light after it passes through the specimen
What are the pros of a light microscope?
Great for viewing living organismsEasy to use, common in schoolsCheaper, smaller, and simpler than other types of microscopesNo need for other special machinery or techniques (ie. vacuum, radiation) to operateObject being viewed retains its natural/authentic color
What are the cons of a light microscope?
Components may not be visible (most cells are transparent) unless using special stains (usually kills the cell)Lower resolution than other types A microscope can only show an image of something that is smaller than the wavelength of light used. Since visible light has a (relatively) long wavelength, and the light is diffracted/scattered as it passes through the matter and lenses, this makes the image blurry at higher magnifications.Maximum useful magnification - 1000xOnly shows a 2D image at higher magnifications
What are the two types of light microscopes?
Compound MicroscopeDissecting (or Stereo) Microscope
What is a compound microscope?
Typically 40x-400x, can view individual cells, 2-D image
What is a dissecting(stereo) microscope?
Typically 7-20x, can only view larger objects, 3-D image
What does an electron microscope do?
Uses a beam of electrons, instead of light, which are focused using magnetic fields
What are the pros of an electron microscope?
Higher resolution images (due to shorter wavelength of electrons vs. visible light)Good for viewing whole cells or individual components Can be used at higher magnifications, up to 1,000,000x
What are the cons of an electron microscope?
Requires sample to go through a special chemical fixation process and then viewed in a vacuumCannot view living cellsMuch more expensive, complicated, larger, and difficult to operate Requires a lot of specialized equipment to work properly and is very sensitive/easy to damage
What are the two types of electron microscopes?
Transmission Electron Microscopy (TEM)Scanning Electron Microscopy (SEM)
What is a TEM microscope?
Transmission Electron Microscopy (TEM)Beams pass through thin samples, creates flat/2D imagesGood for viewing cellular structures and larger proteins
What is a SEM microscope?
Scanning Electron Microscopy (SEM)Beam scans the surface, producing high resolution 3D imagesGood for viewing surfaces of cells
What main thing did Robert Hooke discover?
He described the cork as having box-shaped, pore-like structures, which he called “cells” In 1665, Robert Hooke published observations he made using a microscope, in the book Micrographia.
What did Antonie van Leeuwenhoek discover?
He developed hundreds of simple single lens microscopes with an increased magnification! This allowed him to view organisms in more detailObserved many biological specimens using his single lens microscopes, and sent his findings to the Royal SocietySaw tiny creatures he called them animalcules(Micromolecules)
What did theodor schwann and schleiden discover?
Studied cells along with Matthias Schleiden, compared their studies of animal and plant cellsIn 1839, proposed classical cell theory:All living organisms are made of cellsCells are the basic unit of lifeBoth Schwann and Schleiden were mistaken about the origins of those cells, though, which was correctly identified by another scientist…
What did Rudolf Virchow add to the cell theory?
In 1855, he added a third conclusion to classical cell theory:All cells come from preexisting cells
What is the classical cell theory and what does the modern cell theory add to that?
Classical Cell Theory:- All living things are made up of cells- Cells are the basic units of structure and function in living things- All cells are produced from existing cellsModern Cell Theory adds:- DNA contains hereditary information that is passed from cell to cell during division- All cells are basically the same in chemical composition and metabolic activities- Energy flow occurs within cells
What do all cells(most) have?
Contain DNA (molecule that carries genetic information)Are surrounded by a cell membrane (plasma membrane)Have cytoplasmHave ribosomesOn average range from 5 to 50 micrometers in diameter
What are traits of prokaryotes?
NO nucleusNO membrane-bound organellesThey are simple & unicellular
What are the two types of prokaryotes?
Bacteria vs. Archaea
What is bacteria?
Domain of prokaryotes that contain peptidoglycan in their cell wallsLive almost everywhere (fresh/salt water, land, within and on human bodies, etc)Some a “good” some are “bad” (ie. some “help” other organisms and some cause disease, etc)
What is archaea?
Domain of prokaryotes without peptidoglycan in their cell wallsMost live in extremely harsh environments (acidic, hot, salty, etc.)
What is peptidoglycan?
Polymer of sugars and amino acids that can surround the cell membrane
How do prokaryotes reproduce?
Binary fissionConjugation
What is Binary fission?
type of asexual reproduction in which an organism replicates its DNA and divides in half, producing 2 identical daughter cells.
What is Conjugation?
Process in which some prokaryotes exchange genetic information by moving a cell through a hollow bridge from one cell to another
How do favorable conditions affect asexual reproduction?
In favorable conditions, can grow and divide quickly! As fast as once every 20 minutes!In unfavorable conditions, many form an endospore (a thick internal wall that encloses DNA and a portion of the cytoplasm) that can remain dormant for months or years!
What is an endospore?
a thick internal wall that encloses DNA and a portion of the cytoplasm
What are prokaryotes two categories of their modes of nutrition?
AutotrophsHeterotrophs
How can you further split up auto trophs and heterotrophs?
Photo-AutotrophChemo-AutotrophPhoto-HeterotrophChemo-Heterotroph
What does a Photo-Autotroph do?
-Light as energy source-CO2 as C source
What does a Chemo-Autotroph do?
-Chemicals as energy source-CO2 as C source
What does a Photo-Heterotroph do?
-Light as energy source-Organic compounds as C source
What does a Chemo-Heterotroph do?
-Chemicals as energy source-Organic compounds as C source
Explain good prokaryotes?
Essential in maintaining ecological balance of the living world!Decomposers, Producers, Nitrogen fixers, Human uses
Explain bad prokaryotes?
Bacteria can be pathogensCan damage host tissues and cells, or cause tissue damage when they provoke an immune response (ex. tuberculosis)Can release toxins that act as poison, interfering or killing the host (ex. diptheria)
What are decomposers?
break down dead organisms, supply raw materials
What are producers?
conduct photosynthesis
What are nitrogen fixers?
provide 90% of nitrogen used by other organisms
What are Human uses?
used in wide variety of foods and other commercial products
What are Pathogens?
agents that cause diseases (bacteria and virus can be pathogenic, there are currently no known pathogenic archaea)
What are characteristics of eukaryotes?
Generally larger and more complex than prokaryotes, can be unicellular or multicellularDNA found in nucleus, have dozens of internal structures (organelles)Includes Animals, Plants, Protists, and Fungi
What is the Endosymbiotic theory?
The endosymbiotic theory states that some of the organelles in today’s eukaryotic cells were once prokaryotic microbes
What is some evidence for the endosymbiotic theory?
Mitochondria and chloroplasts are both similar in size to bacteria and contain their own DNA, ribosomes, and double membrane. This single stranded DNA is found exclusively in prokaryotes.Chloroplast membranes closely resemble the membranes of photosynthetic prokaryotesSome cells today contain bacteria and algae living in an endosymbiotic relationship
What is Asexual Reproduction?
a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes.
What is Mitosis?
Eukaryotes reproduce asexually in the process of mitosis.A part of the cell cycle in which replicated chromosomes are seperated into two new nuclei.
What is the microscope term resolution?
Shortest distance btwn two places on one specimen that can be identified as different
What is the microscope term field of view?
what you can see through the microscope lens
What is the microscope term Depth of field?
the range in which the object can still be clearly seen
What is the microscope term magnification?
when a microscope creates an image a differnt size to the actual object it is looking at.
What are the important structures in prokaryotes?
DNARibosomesCell Walls Cell MembranePiliFlagella
What is DNA? In prokaryotes
free-floating in cytoplasm, contain genetic information
What are Ribosomes? In prokaryotes
Synthesize proteins
What are Cell Walls? In prokaryotes
Shapes, supports, and protects cell
What is a Cell Membrane? In prokaryotes
Regulates materials entering and leaving cell
What is Pili? In prokaryotes
Short, hair-like structures on cell surface, usually involved in adherence to surfaces
What is Flagella? In prokaryotes
Primarily used for cell movement
What does cocci and bacilli mean?
Cocci - sphericalBacilla - rod shaped
What do diplo, strepto and staphylo mean?
Diplo - = two cellsStrepto - = chain of cellsStaphylo - = cluster of cells
What do Spirillum and spirochete look like?
spirillum is short spaghet and spirochete is long spaghet
What is a gram stain?
A common way to distinguish between types of bacteria, All bacteria (but not archaea!) have peptidoglycan in their cell walls.
What is a gram-negative bacteria?
Gram-negative bacteria have a thin layer of peptidoglycan
What is a gram-positive bacteria?
Gram-positive bacteria have a thick layer of peptidoglycan
What are the main compartments of a eukaryote?
Main compartments = nucleus + cytoplasm
What is the cytoplasm?
semifluid substance, contains everything not in a nucleusMedium for chemical reactions, allows movement through the cell, suspends organelles
What is the nucleus?
Surrounded by nuclear envelope (double-membrane)Nuclear pores in envelope Chromatin is found hereThe Nucleolus
What are nuclear pores?
allow materials to move in and out of nucleus
What is chromatin?
(the spread out form of chromosomes, which are made of DNA)
What is the Nucleolus?
is a small dense region where ribosomes are produced and assembled
What is the endoplasmic reticulum?
Intricate membrane system Has SER and RER
What is SER?
Smooth endoplasmic reticulum (SER) makes and transports lipids, phospholipids, and steroids
What is RER?
Rough endoplasmic reticulum (RER) makes proteins and other membrane parts. Also modifies, sorts, and transports proteins!
What is the ribosome?
Site of protein synthesisMade of rRNA and proteins( and polypeptides)2 subunits: Large(puts amino acids together to form polypeptides) and Small(decode the RNA)Eukaryotes have bigger ribosomes then prokaryotes
What is the Golgi Apparatus?
Processes, sorts, and transports membrane proteins and other secreted proteinsCis face receives, trans face “ships” out(check notes for better explanation)Transport vesicles bud off the trans face to take the protein to the next organelle or to the membrane to be exported
What are Vacuoles?
Stores materials (water, salts, proteins, waste, carbohydrates, etc)Many plant cells have one central vacuole, unlike animal cells
What is the Cytoskeleton?
Network of protein filaments in eukaryotes Helps give shape to cell, provide structure/organization, transport materials along the filaments, and can help the cell moveMicrofilaments and Microtubules
What are Microfilaments?
made of actin(proteins),small, threadlike
What are Microtubules?
made of tubulins(proteins),bigger, hollow, important in cell division
What is Myosin?
Myosin is a motor protein that can “walk” along actin to help move things inside the cell.
What are Vesicles?
Surrounded by membrane, transport materials from one place to another (or out of the cell)Formed by pinching off other organelle (ex. Cell membrane, Golgi apparatus, etc)Fuse with target organelleSome store enzymes that need to be stored at different pH than cytoplasm
What are Lysosomes?
Surrounded by membrane, contain hydrolytic enzymes Break down macromolecules or old organelles into small molecules that the cell can reuse (“recycling”)Common in animal cells, rare in plant cells (central vacuole does this instead)Example:Old protein can be broken down into its individual amino acids, which the cell could then use to make other new proteins!
What is the Mitochondria?
Breaks down food (glucose) to generate useable energy (ATP) for the cellContains its own DNA and ribosomesDouble membrane (inner + outer)Both plants and animals have theseSpace between inner and outer is the inter matrix
What is the Chloroplast?
Captures energy from sunlight and converts it into stored chemical energy (glucose)Contains chlorophyllDouble membrane (inner + outer)Has its own DNA and ribosomesAnimals do NOT have these
What is the Fluid Mosaic Model?
The membrane is a “mosaic” of many different things (phospholipids, proteins, cholesterol, etc) that can move around fluidly within the membrane.
What is the Plasma Membrane?
Thin, flexible barrier around all cellsSelectively permeableRegulates what enters or leaves the cell
What are the Plasma Membrane Components?
Phospholipid, Membrane Protein, Cholesterol, Carbohydrates,
What are the Plasma Membrane Components(Phospholipid)?
Main component of the membraneLipid made of two fatty acid, a phosphate group, and a glycerol moleculeAmphipathicHydrophilic headHydrophobic tail
What are the Plasma Membrane Components(Membrane Protein)?
Membrane ProteinsProteins within the membraneCan be partially within, all the way through, or just loosely attachedMany roles, including signaling, transport, attachment, etc.
What are the Plasma Membrane Components(Cholesterol)?
Lipid made of four fused carbon ringsHelps maintain correct fluidity and stability
What are the Plasma Membrane Components(Carbohydrates)?
Attached to proteins or lipids, on outer surfacePlay role in cell recognition, etc.GlycoproteinsGlycolipids
What is the Cell Wall?
Strong supporting layer around cell membraneMaintains shapeProtects against mechanical stressMost prokaryotes and eukaryotes (ex. plants, fungi) have them, but animals do notPorous, typically allow water, oxygen, carbon dioxide, etc, to pass through
What is Cilia?
Cilia = tiny, hair-like, MANY, many rolesONLY in eukaryotic cells
What is a missle cell?
Single layer of phospholipids
What is a concentration gradient?
Substances will naturally move from HIGH to LOW concentration.Eventually, an equilibrium would be reached (no gradient remaining).
What is Passive Transport?
No energy required!High to low (concentration)Easy peasy :)
What is Active Transport?
Energy is required!Low to high (concentration)Not easy peasy :(
What are the types of Passive Transport?
Diffusion, Facilitated Diffusion, Osmosis
What is Diffusion?
Particles move from high to low until reaches equilibrium
What is Facilitated Diffusion?
When molecules can’t go directly across a membrane, so they pass through special protein channels
What is Osmosis?
Diffusion of water through a selectively permeable membrane Through the membrane directly and in larger quantities through aquaporins Water will move across a membrane until the concentration of solute is the same on both sides!Solute vs. SolventSugar can’t move across the membrane by itself, it’s too large
What is Dynamic Equilibrium?
The substances will continue to move, but there is no net change in concentration on either side! Movement doesn’t stop entirely!
What are the different types of solutions?
Hypotonic Solution, Hypertonic Solution, Isotonic Solution
What is a Hypotonic Solution?
Water diffuses INTO cellCell expands
What is a Hypertonic Solution?
Water diffuses OUT OF cellCell shrinks
What is a Isotonic Solution?
Water moves in and out equallyCell stays the same
What is Lysed?
Bursts
What is Turgid?
Bloated
What is Flaccid?
Droopy
What is the optimal solution for an animal cell?
Isotonic Solution
What is the optimal solution for a plant cell?
Hypotonic Solution
What are the types of active transport?
Selective and Bulk Transport
What is Selective Transport?
Small molecules, ionsProteins in membrane are used
What is Bulk Transport?
Large molecules, clumps of materialsMovements of the cell membrane itself
What are the types of bulk transport?
Endocytosis and Exocytosis
What is Endocytosis?
“endo” = withinMaterial is taken into cell by infolding of the cell membranePhagocytosis and Pinocytosis
What is Phagocytosis?
taking up particles and packing within food vacuole“cell eating”
What is Pinocytosis?
= taking up liquid from surrounding environment“cell drinking”
What is Exocytosis?
“exo” = out ofMaterial is released from the cell by vesicle fusing with membraneSignaling molecules, waste, toxins, etc.
What is the Primary Active Transport?
Uses ATP as the energy source. A very common example is the sodium-potassium pump!
What is the Secondary Active Transport?
Uses the energy stored in electrochemical gradients Ions have charges, and when there’s an imbalance in charges on either side of the membrane, there is a membrane potentialThe combination of concentration and membrane potential = electrochemical gradient!BOTH will affect which way things move across the membraneSo, a primary active transport protein can set up this electrochemical gradient, which the secondary active transport protein can then use!
What is Uniport?
Passive transport or primary active transport1 direction of travel, 1 thing traveling
What is Symport?
1 direction of travel, 2 things traveling
What is Antiport?
2 directions of travel, 2 things traveling
What do Symport and Antiport have in common?
Cotransport
What do cells need to be able to do?
Get information from their surroundings and other cellsSend information out for other cells to receiveIn multicellular organisms, be able to coordinate complex functions that involve many different cellsCommunicate within themselves! (ex. organelle to organelle)
What is a ligand?
Signaling molecule that binds to a certain receptor
What is a receptor?
A protein that “receives” the ligand and causes some effect
What is a target cell?
A cell that has the receptor for a particular ligand
What is a non-target cell?
A cell that does NOT have the receptor for a particular ligand
What are the three stages of cell communication?
Reception, Transduction, and Response
What are the types of receptors?
Internal receptorsCell-surface receptors
What are internal receptors?
In cytoplasmLigand has to enter cell to bind
What are cell-surface receptors?
In cell membraneThree main types:Ion-channel linked receptorsG-protein coupled receptorsEnzyme-linked receptors
What is a ion-channel linked?
When the ligand binds, the transmembrane channel opens, allowing ions to move through it.
What is a G-protein coupled?
When the ligand binds, the receptor interacts with a G-protein which starts the signal transduction chain of events.The receptor has seven transmembrane regions.GTP to GDP
What is an enzyme-linked?
When the ligand binds, the receptor activates an enzyme, which starts the signal transduction chain of events.
What is a signal transduction?
IntracellularSeries of signaling events, like a chain reaction
What are the responses to cell signaling?
Depends on the particular signal! But, often:Changes in gene regulationTurning expression of certain genes on/offRegulates another protein’s activity
What are examples of responses to cell signaling?
A growth factor binding to a cell causes an increase in the expression of genes that allow the cell to grow and divide!When adrenaline binds to a muscle cell, it inactive the enzyme responsible for storing glucose and activates the enzyme responsible for producing glucose!
What is bacterial communication?
At a certain density, the cells “decide” to change what they are doing. This works by the bacteria cell producing a ligand. When there is a low density of cells, there are less receptors for the ligand to bind to which results in no cellular response. When there is a higher concentration, there are more ligands and receptors. Once the ligands bind, they activate specific genes in the chromosomes of bacterial cells.
What is bacterial communication examples?
Biofilm. The biofilm creates optimal conditions for the further growth of the organisms living within it.
What is direct contact?
Signaling between cells that are touching one another. This allows substances to move from one cytoplasm to the next
What is paracrine?
Paracrine signals move by diffusion through the extracellular matrix. This causes a quick response that lasts a short amount of time. The ligands are quickly degraded by enzymes to keep the concentration gradient.
What is autocrine?
The cell releases a ligand that binds to a receptor on the cell that released it.
What is endocrine?
The Cell releases ligands that travel through the circulatory system slowly. They connect to the receptor of the target cell and are active for a very long time(since there is a low concentration of them). These ligands are called hormones.
What is direct contact examples?
Gap junctions, like cardiac muscles within the heart. It’s important for the muscles to communicate quickly so that their contractions happen simultaneously, allowing the heart to beat properly.
What is paracrine examples?
An example of this is between nerve cells. To allow signal transmission between cells to be fast, they use Paracrine. This enables an immediate response.
What is autocrine examples?
An example is in the early development of an organism to ensure that cells develop into the correct tissues and take on the proper function.
What is endocrine examples?
An example of this is the pancreas, one of the endocrine glands that regulates the body’s blood glucose levels. Produces Insulin that travels through the bloodstream and connects to a liver cell receptor. This produces glycogen that can store glucose for later.
What is cellular respiration?
Process that cells use to release energy by breaking down glucose and other food molecules Composed of three main partsMost parts of cellular respiration require oxygen (which is why we need to breathe!)“Respiration”ALL cells must carry out some version of cellular respiration to have energy to live!Cells that live in anaerobic environments can only do the anaerobic parts!
What is aerobic?
requires oxygen
What is anaerobic?
does not require oxygen
What are the three stages of cellular respiration and are they anaerobic or aerobic?
GlycolysisAnaerobicKrebs CycleAerobicElectron Transport ChainAerobic
What is glycolysis?
“Sugar-breaking”Molecule of glucose is broken down into two molecules of pyruvic acidGlucose = 6 carbonsPyruvic acid (also called pyruvate) = 3 carbonsNeeds 2 ATP for the process to begin, and produces 4 ATPNET GAIN OF 2 ATP PER GLUCOSE MOLECULEAlso produces 2 NADH moleculesPasses 4 high energy electrons to NAD+NADH is used later in the electron transport chainOccurs in the cytoplasmAnaerobicDoes NOT require oxygen
What is glucose broken into
Molecule of glucose is broken down into two molecules of pyruvic acid
Does glycolysis require oxygen?
Does NOT require oxygenAnaerobic
Where does glycolysis occur
Occurs in the cytoplasm
How much ATP does glycolysis produce?
Needs 2 ATP for the process to begin, and produces 4 ATPNet 2 ATP
How much NADH molecules does glycolysis produce?
Also produces 2 NADH moleculesPasses 4 high energy electrons to NAD+NADH is used later in the electron transport chain
What are electron carriers?
Allow a cell to move electrons around as needed
What are the electron carriers involved in cellular respiration?
Ex. in cellular respiration: NADH and FADH2
Where is the mitochondria found?
Found in cytosol of the cell
What is a cristae?
Inner membrane has cristae (many inward protrusions)Increases surface area!
What is intermembrane space?
space between double membranes
What is the mitochondrial matrix?
compartment within inner membrane
Why is the multi-compartment structure important for the mitochondria?
helps keep reactions separate and maintain different molecule concentrations in certain areas
What is the Krebs Cycle(Citric Acid Cycle)
Pyruvate enters the mitochondriaPyruvate is first converted to acetyl-CoA in order to prepare for the cycleThis conversion produces 1 NADH and 1 molecule of CO2Occurs in mitochondrial matrixAcetyl-CoA (generated from pyruvic acid) is broken down into carbon dioxide in a series of energy-extracting reactionsCycle turns twice per original glucose molecule1 glucose = 2 pyruvateEach turn of cycle = 1 ATP producedPer glucose = 2 ATP producedAerobic, occurs in matrix
What is pyruvate turned into before krebs cycle?
Pyruvate is first converted to acetyl-CoA in order to prepare for the cycle
Where does the krebs cycle occur?
Occurs in mitochondrial matrix
How much NADH does the krebs cycle produce?
6 NADH
How much CO2 does the krebs cycle produce?
4 CO2
How much ATP does the krebs cycle produce?
2ATP
How much FADH does the krebs cycle produce?
2 FADH
What is the Electron Transport Chain(ETC)?
Series of electron carrier proteins that shuttle high-energy electrons during ATP-generating reactionsOxidative PhosphorylationElectron carriers were made in glycolysis & Krebs cycleNADH and FADH2ATP Synthase = generates ATP from ADPOccurs in inner mitochondrial membraneRegenerates electron carriersGenerates electrochemical gradient
What does ETC produce? How Much?
Produces water and ~32 ATP
What is ATP Synthase?
generates ATP from ADPWorks similarly to a water turbine in a power plantH+ ions instead of waterProcess is called chemiosmosis
Where does ETC occur?
Occurs in inner mitochondrial membrane
Where are electron carriers made that are used in ETC?
Electron carriers were made in glycolysis & Krebs cycle
What is chemiosmosis?
Energy stored in proton gradient used to do work
What is the chemical equation for cellular respiration?
C6H12O6 + 6O2 —> 6CO2 + 6H2O + ATP
What is anaerobic respiration?
Anaerobic Steps:GlycolysisFermentationLactic AcidEthanol/Alcohol
Where does anaerobic respiration occur?
Cytoplasm
What is the goal of fermentation?
Allows you to continue to conduct glycolysis to generate those 2 ATP over and over again!Steady supply of ATPNowhere near as much energy as aerobic respiration, but better than nothing!
What are the types of fermentation?
Alcohol Fermentation and Lactic Acid Fermentation
What is Alcoholic Fermentation?
Produces CO2 and Ethanol/Alcohol and NADHPyruvic acid + NADH —> Alcohol + CO2 + NAD+
what is Lactic Acid Fermentation?
Produces Lactate and NADHPyruvic acid + NADH —> Lactic acid + NAD+
What are common uses for alcoholic fermentation?
Used to produce alcoholic drinks and biofuelProcess that causes bread to rise
What are common uses for Lactic Acid fermentation?
Food processing and preservation, such as pickles, sauerkraut, kimchi, yogurt, cured fish/meatsQuick bursts of energy for humans! (<90 s)
Why is photosynthesis important?
Not only does it capture energy from outer space (the Sun) and convert it into compounds that all life on Earth can use…… but it also produces oxygen, for aerobic organisms to breathe/use!
What is photosynthesis?
Uses energy from sunlight to convert water and carbon dioxide (low energy reactants) into sugar and oxygen (high-energy products)These sugars can then be used to produce complex carbohydrates (like starch) or provide energy for their cells to do work(sunlight) + 6CO2 + 6H2O —> C6H12O6 + 6O2
What organisms conduct photosynthesis?
Plants, algae, and cyanobacteria
What is the chloroplast?
Where photosynthesis takes placeFound in plants and other organisms (not animals)Contain chlorophyll
What is stroma?
Fluid inside of chloroplast(kinda like cytoplasm)
What is granum?
Stack of thylakoids
What are thlakoids?
Where light-dependent reaction happens
What is chlorophyll?
A pigment that absorbs certain wavelengths and reflects others
What are the types of chlorophyll found in plants? What light do they reflect/absorb?
Two types found in plants, chlorophyll a and bThese REFLECT green light, which is why plants look green!Thus, they ABSORB light that isn’t green, especially blue/violet and red light
What are the phases of photosythesis?
Light-dependent reactions and Calvin Cycle
Where does the light-dependent reaction occur?
In thylakoid
What is the light dependent reaction?
Sunlight absorbed, energy produced converts NADP+ and ADP into NADPH and ATPWater is required (source of electrons and hydrogen atoms)Oxygen is released
What is a photosystem?
clusters of chlorophyll (light absorbing pigments ) and proteins in the thylakoid
What is photosystem II
Absorbs light, excites electrons, those electrons get passed to an electron transport chain
What is photosystem I
After electrons pass through ETC, this photosystem uses light energy to reenergize the electrons, which are picked up by NADP+ and H+
What are the Reactants of the light-dependent reaction?
Light + H2O + NADP + ADP
What are the Products of the light-dependent reactions?
O2 + NADPH + ATP
What is the light independent reaction?
In stromaATP and NADPH from light dependent reaction are used to produce glucose from CO2Carbon dioxide required, absorbed from atmosphere
Where does the light independent reaction occur?
In stroma
What are the reactants of the light independent reaction?
CO2 + NADPH + ATP
What are the reactions of the light independent reaction?
Glucose + NADP+ + ADP
What is carbon fixation?
CO2 molecule enters the cycle and combines with other carbon compounds
What is reduction in the calvin cycle?
ATP and NADPH are used to make G3P, which goes off to make glucose
What is regeneration in the calvin cycle?
Some G3P molecules stay to be recycled, so the cycle can continue!
What is genetics?
The study of heredity
What is fertilization?
The joining of male and female gametes to produce a new cell
What is true-breeding?
self-pollinating plants that produce offspring identical to themselves
What did Gregor Mendel do?
Mendel used cross-pollination of true-breeding plants to produce new combinations and study the results.Gregor Mendel was the father of geneticsHe also used peas BECAUSE they were self-pollinating which can lead to true-breeding plants.
What are genes and alleles IN GENERAL?
An individual’s characteristics are determined by factors that are passed from one generation to the next.
What is a gene?
sequence of DNA that codes for a protein and thus determines a trait; factor that is passed from parent to offspringExample: There is a gene that determines the trait for hair color
What is an allele?
Different forms of a gene. Example: The possible alleles for the gene for hair color include brown, black, blonde, red, etc.
What is a dominant trait?
An organism with one dominant allele will exhibit the dominant form of the trait.
What is a recessive trait?
An organism must have two copies of the recessive allele to exhibit the recessive form of the trait.
In Mendel’s experiments, what is the P Generation?
Parental generation; true-breeding
In Mendel’s experiments, what is the F^1 Generation?
First filial generation; offspring of the P cross
In Mendel’s experiments, what is the F^2 Generation?
Second filial generation; offspring of the F1 cross
In Mendel’s experiments, what happened in the F^1 Cross?
All offspring looked like one parent from the P generation.
In Mendel’s experiments, what happened in the F^2 Cross?
Most offspring look like the F1 generation but approximately ¼ look like the second parent from the P generation.
What is the Law of Segregation?
During gamete formation, alleles segregate from each other so that each gamete carries only a single copy of each gene. Each F1 plant produces two kinds of gametes: those with the tall allele and those with the short allele. The alleles separate during gamete formation and then pair up again in the F2 generation (fertilization), with the capital letter representing the dominant allele and the lowercase letter representing the recessive allele. The F2 generation had new combinations of alleles!
What is probability?
The likelihood that a particular event will occur. Example: When you flip a coin, there are two possible outcomes. The probability of either outcome is theoretically equal, so the probability that a single coin flip will land heads up is 1 out of 2, ½, or 50%.
What is monohybrid?
crossing of one trait
What is dihybrid?
crossing of two traits
How do you express PHENOTYPIC RATIO in a MONOHYBRID cross?
Dominant : Recessive3:1
How do you express PHENOTYPIC RATIO in a DIHYBRID cross?
dominant for both traits : # dominant for first trait but recessive for second : # recessive for first trait but dominant for second : # recessive for both traits9: 3: 3: 1
How do you express GENOTYPIC RATIO in a MONOHYBRID cross?
Homozygous dominant (HH) : heterozygous (Hh) : homozygous recessive (hh)1 : 2 : 1
How do you express GENOTYPIC RATIO in a DIHYBRID cross?
RRYY:RRYy:RrYY:RrYy:RRyy:Rryy:rrYy:rrYy: rryyDom,Dom: Dom,Het: Het,Dom: Het,Het: Dom,Rec: Het,Rec: Rec,Dom: Rec,Het: Rec,Rec1:2:2:1:4:1:2:2:1
If you had two traits, how would you go from genotype to gametes?
Foil to get something likeAaBb to —-> AB Ab aB ab
What is incomplete dominance?
One allele is not completely dominant over another Result = a different phenotype, a sort of “blend”RWC^RC^WRR’
What is Codominance?
BOTH phenotypes are clearly expressed(human blood types demonstrate codominance!)Result = both traits clearly visible together, stripes/spots/multiple proteins/etc.RWC^RC^WRR’
What is multiple alleles? Ex
A gene that has more than just two allelesEx. There are three alleles for human blood type (A, B, & O)So, human blood type exhibits codominance and multiple alleles!
Explain Human Blood Type and how the Antigens Work?
Red blood cells carry antigens which trigger an immune response. There are two types of antigens, A and B. People with type A blood have the A antigen, type B people have the B antigen, type AB have both, and type O have neither. Both A antigens and B antigens are clearly expressed and are written IA and IB while having no antigens is written i.
What is the + and - on blood types?
There are also “+” vs. “-” blood types!Rh is just another antigen on RBCs!
What is Sex-Linked Inheritance?
A gene for a trait is found on the X or Y chromosomesGenes on Y - only found in malesRecessive alleles found only on X - trait is more likely in males*assuming XX vs XY chromosomes, and not any other combinations!**
What is a polygenic trait?
A trait is controlled by two or more genes.Often results in a range/spectrum of phenotypes!!Ex: height, skin color, eye color
What is mitochondrial inheritance?
In humans all (or nearly all) of our mitochondria come from the cytoplasm of the ovum (egg cell)!Thus, offspring typically have identical mitochondrial DNA to their mother!
What are the things that effect your genotype? EX
Environmental conditions can affect gene expression!Phenotype depends on genes + environmentSIAMESE CAT WITH TEMPERATUR SENSITIVE
Prokaryote chromosomes vs Eukaryotes chromosomes?
Pro:singular, circularin cytoplasmEu:multiple, linearmorein nucleus
What is DNA coiled around and what does that form?
DNA is tightly coiled around histones, which form nucleosomes
What is X-Shape?
duplicated chromosome with supercoiled chromatin
What are the main roles of DNA?
Storing information:Genetic infoCopying information:Prior to division (during S phase) it has to be copied!Transmitting information:Genes are inherited from one gen to the next
What are the monomers of DNA
Nucleotides
What is the DNA structure?
Double-strandedDouble helix (linear in euk, circular in pro)Monomers = nucleotides5’ to 3’ directionality 5’ = phosphate end3’ = OH endAntiparallelHydrogen bonds between bases
What is Chargaffs Rule?
“Chargaff’s Rule”# of A=T# of C=G# of purines = # of pyrimidines
What are the Base-Pairing Rules DNA
Adenine with thymine (2 H bonds)Guanine with cytosine (3 H bonds)
Describe the Contents of Nucleotides?
Monomers of DNAComposed of three chemical groups:5 Carbon Deoxyribose SugarCarbons are numbered for biochemical identification purposes Phosphate Attached to the 5’ deoxyribose carbon1 of 4 Nitrogenous bases
Base Pairs?
A-T/UG-C
What are Euk Telomere?
Eukaryotic DNA has ends Prokaryotic doesn’t because it is stored as a circular chromosome. These ends can be degraded over time, leading to gene loss.Eukaryotes have “caps” of long nonsense DNA sequences called telomeres to protect against DNA degradation. Many scientists speculate that telomere loss is associated with aging in eukaryotes.
What is the central dogma?
Describes the flow of information in a cellDNA–>RNA–>ProteinProteins carry out cell functions, which is expressed as a physical trait*.
What is Semi-Conservative Replication?
Each copy of the DNA will have one template (old) strand and one newly synthesized strand.
3 steps to DNA Replication?
Initiation, Elongation, Termination
What is Initiation in DNA Replication?
Topoisomerase (A) relaxes the supercoiled DNA near the origin of replication. DNA Helicase (B) breaks the hydrogen bonds between the template strands. Strands are kept from re-annealing (fancy word for binding) by single stranded binding proteins (C).
What is Elongation in DNA Replication?
Primase puts down RNA primers to help DNA polymerase actually bind to the template DNA StrandDNA Polymerase binds and synthesizes the new strands from 5’ to 3’.Replication on the leading template strand is continuous. Replication on the lagging template strand is discontinuous
What is Termination in DNA Replication?
RNA primers are removedDNA ligase fills in the gaps from the primer removal and between the Okazaki Fragments.End result: Two Identical Copies of the DNA
What is a gene?
sequence of DNA that codes for a particular protein
DNA vs RNA
Sugar usedT vs UDouble vs single stranded
Types of RNA
tRNAmRNArRNA
tRNA
T-shaped structure made of RNA nucleotides. Amino acids are attached on the top, and the anticodon is on the bottom loop.Transfer RNA (tRNA) is responsible for carrying amino acids to the ribosome during translation and transferring them on to the growing polypeptide (amino acid) chain.
mRNA
Single stranded sequence of RNA nucleotides.Messenger RNA (mRNA) is an RNA copy of a gene that carries the instructions for producing a specific protein from the nucleus to the ribosome.
rRNA
Sequence of RNA nucleotides that bind to ribosomal proteins in order to form the whole ribosome. Ribosomal RNA (rRNA) is a structural component of ribosomes that assists with translation of messenger RNA .
Transcription in Prokaryotes vs. Eukaryotes
PROKARYOTESOccurs in the cytoplasmNo processing requiredEUKARYOTESOccurs in the nucleusProcessing required before leaving nucleus
What is a promoter?
Certain DNA sequences right before genes, where proteins bind to initiate transcriptionTFs = regulateTranscription factors
What is RNA polyamerase?
puts RNA nucleotides together in a growing chain using DNA strand as a templatealso unzips DNA like Helicase!makes RNA strand in 5’ to 3’ direction!
What is a 5’ Cap?
Specially modified guanine nucleotide that is added to the 5’ end of the transcript. It protects the mRNA from degradation in the cytoplasm and also helps the ribosome to bind at the the mRNA start codon to initiate translation.
What is a exons?
Sequences of mRNA that actually code for part of the protein.
What is a introns?
Sequences of mRNA that exist between exons and allow for alternative splicing.
What is a Poly A Tail?
A series of A nucleotides added to the 3’ end of the transcript. It aids in nuclear export ,protects the mRNA from degradation in the cytoplasm, and also helps the ribosome to bind at the the mRNA start codon to initiate translation.
Purpose of 5’ cap?
modified guanine nucleotide
Purpose of Poly A Tail?
aids in nuclear export
Purpose of of 5’ Cap and Poly A Tail?
protects from degradation, help ribosome to bind
What is alternative splicing?
Alternative splicing, or alternative RNA splicing, or differential splicing, is an alternative splicing process during gene expression that allows a single gene to code for multiple proteins. In this process, particular exons of a gene may be included within or excluded from the final, processed messenger RNA (mRNA) produced from that gene.[1] This means the exons are joined in different combinations, leading to different (alternative) mRNA strands. Consequently, the proteins translated from alternatively spliced mRNAs will contain differences in their amino acid sequence and, often, in their biological functions
Where does Eukaryotic Translation occur?
Eukaryotic translation occurs on ribosomes attached to the rough endoplasmic reticulum or those found free-floating in the cytoplasm.
What is a codon?
three bases in mRNA that code for a particular amino acid
What are the processes of Translation?
Initiation, Elongation, Termination
What is Initiation in Translation?
Large and small subunit of the ribosome bind to the start codon. The small ribosomal subunit binds to the mRNA (aided by interaction with rRNA) The tRNA that matches the start codon (AUG) base pairs, followed by the large ribosomal subunit binding.
What is Elongation in Translation?
The ribosome reads the mRNA in sequences of 3 nucleotides called codons.Ribosome translocates from codon. At each codon the matching tRNA binds to the mRNA, transfers its specific amino acid to the growing polypeptide chain
What is Termination in Translation?
Ribosome continues translating until it reaches the stop codon. Translation of the stop codon results in a release factor protein binding to the ribosome, causing it to release both the mRNA and the newly synthesized polypeptide
What is gene linkage?
Genes on the same chromosomes can “break” the law of independent assortment The closer together they are, the most likely they are to be “linked”Unlikely to be split apart during crossing over in Meiosis I
What is the law of independent assortment?
Alleles get independently assorted
How are gene map units created and used?
Crossover frequencies can be converted into map units.We can use the frequency of crossing-over to determine the relative distance between genes on the same chromosome.
What is the purpose of Human Pedigrees?
Shows presence or absence of a trait according to relationships within a family across generations
Autosomal Inheritance Dominant Traits? EX
every individual with the trait must have a parent with itwithout any other context, shading = AA or AaExample = Huntington’s disease
Autosomal Inheritance Recessive Traits? EX
individual with the trait may or may not have a parent with itwithout any other context, shading = aaNon-shaded could be AA or Aa!Example = Sickle Cell Anemia
X-Linked Dominant Traits? EX
females are more likely to show dominant traitsshading = XAXA, XAXa, XAYExample = X-linked hypophosphatemia (XLH)
X-Linked Recessive Traits? EX
males are more likely to show recessive traitsshading = XaXa, XaYNon-shaded could be XAXA, XAXa, or XAYExample = Red-green colorblindness
What is a mutation?
A change in the genetic material
What are two main types of mutation?
Gene mutationChromosomal mutation
What is Locus?
Location of gene or DNA sequence
What is Germ-line mutation?
From gametes
What is Somatic Mutations?
Not gametes
What is wild type protein?
normal protein
What is point mutation?
a change in one base pair of the sequence
What are the types of point mutations?
Silent, Missense, Nonsense
What is Silent Mutations?
Has no effect on the protein sequence
What is Missense Mutations?
Results in an amino acid substitution
What is Nonsense Mutations?
substitutes a stop codon for an amino acid
What is Frameshift Mutations?
A deletion or insertion of bases can cause a frameshift
What can Cause Mutations?
Spontaneous Mutationserrors in DNA replication, etc.Induced Mutationscaused by mutagens
What are some examples of disorders caused by mutations?
Sickle Cell Disease, Huntington’s Disease
What is Sickle Cell Disease?
Single gene mutation (point - substitution)Hemoglobin-Beta gene on chromosome 11Autosomal recessive“Heterozygous advantage”
What is Huntington’s Disease?
Insertion of “CAG” repeats in gene for a protein in brain neuronsChromosome 4Autosomal dominant
What is a human karyotype?
A human karyotype shows 22 pairs of autosomes and 1 pair of sex chromosomes.
When does non-disjunction happen and also what is it?
Could happen in M1 or M2If in M1 then no normal cellsIf in M2 then half normal cellsIs improper splitting of chromosomes
What is Monosomy?
1 copy
What is Trisomy?
3 copies
What is Aneuploidy?
An abnormal number of chromosomes
What is Polyploidy?
Having more than two complete sets of chromosomes Relatively common in plants, but rare in animals!
What is X-Chromosome Inactivation
In females, one X chromosomes is “switched off” and forms a Barr Body
What are lethal traits?
A trait in which a homozygous dominant individual does not survive.This affects probability estimates!
