Cell Biology Flashcards
All information that was taught to me while attending Vanier College's "Animal Health Technology" Program, located in St-Laurent Montreal.
What is biophilia?
The love of living things
What is biology ?
The science of the study of life
What are Cyanobacteria ?
Bacteria capable of photosynthesis
What is life?
Made up of at least 1 cell. Way of capturing and using energy and raw materials
When did life begin?
3.8 billion years ago with chemical origin of the first living cell
Prokaryotic cells contain :
Plasma membraneCytoplasmDNANucleoidRibosomes
Eukaryotic cells contain
Plasma membraneCytoplasmDNANucleusRibosomes
Cyanobacteria means what
Capable of photosynthesis
What is nature?
Everything in the universe except for what humans have manufactured
What are atoms?
Fundamental building blocks of all substances
What are molecules?
Consisting of two or more atoms
What is a cell?
Smallest unit of life
What is an organism ?
An individual consisting of one of more cells
What is a population?
Individuals of the same species in the same area
What is a community?
Populations of all species in same area
What is an ecosystem?
A community and it’s environment
What is a biosphere?
All regions of the earth where organisms live
What is an emergent property?
A characteristic of a system that does not appear in any of its component parts
What is an animal?
Multicellular consumer, life stages , mobile
What is an archaeon ?
Single celled, no nucleus, closely related to eukaryotes
What is a bacterium?
Single celled, no nucleus
What is biodiversity?
Variation among organisms
What is a prokaryote?
Cell with no nucleus
What is a fungus?
Single celled/multicelled, digests outside body, absorbs released nutrients, decomposer
What is a nucleus?
A sac that encloses DNA
What is a plant?
Multicelled producer by photosynthesis
What is a protist
Part of group of eukaryotes
What is a genus?
A group of species that share unique features
What is a species?
Individuals that share one or more heritable traits and can interbreed.
What are the three domains that organisms are classified into?
Bacteria, archaea, eukarya
What is energy?
The capacity to do work
What is a nutrient?
Atom/molecule that has an essential role in growth and survival that an organism cannot make for itself
What are producers?
Acquire energy and simple raw materials from environmental sources to make their own food
What is photosynthesis?
Sunlight energy to make sugars from carbon dioxide and water
What are consumers?
Cannot make their own food, get energy and nutrients indirectly by eating producers and other organisms
What are decomposers?
Feeds on waste or remains of organisms
What is a receptor?
Molecule or cellular structure that responds to a specific form of stimulation.
What is homeostasis
Adjustment to change allows organisms to keep conditions in their internal environment within a range that favors cell survival
What is DNA?
Nucleic acid and source of each individual’s distinct figures
What is inheritance
Transmission of DNA from parents to offspring
What is reproduction?
Actual mechanisms by which parents transmit DNA to offspring
What is development ?
The orderly transformation of the first cell of a new individual into an adult
What is a species?
A kind of organism
What is a genus?
First part of a two part name for a species
What is a bacteria?
Single celled organism
What does prokaryotic mean?
Bacteria containing no nucleus.
What are archaeons?
They are the same as prokaryotes but evolutionally closer to eukaryotes
What are eukaryotes?
An organism with a nucleus
What are Protists?
Simplest kind of eukaryotes
What are fungi
Multicelled and eukaryotic organisms
What are plants?
Multicelled eukaryotes
What are animals?
Multicelled eukaryotes that ingest tissue or juices of other organisms
What are mutations ?
Small scale changes in DNA
What is an adaptive trait?
Trait that has changed in a way that makes an individual better suited to his environment
What is natural selection?
Differential survival and reproduction of individuals in a population that differ in the details if their heritable traits
What is evolution
Change in the line of decent
What is critical thinking?
Judging information before accepting it
What is science?
The systematic study of nature
What is scientific theory
A hypothesis that has not been disproved after years of tests
What are experiments
Tests that can support or falsify a prediction
What is a variable?
Characteristics that differs among individuals or events
What is an experimental group :
Group of individuals that recieve a certain treatment
What is a control group?
Identical to experimental groups but missing one characteristic
What is a sampling error
What is a sampling error?
What are atoms ?/
Particles that are the building blocks of all substances
What are protons?
Subatomic particles carrying a positive charge
What are neutrons?
Subatomic particles carrying no charge
What are electrons?
Subatomic particles carrying a negative charge
What is a charge?
An electrical property that attracts/repels other subatomic particles
What is an atomic number?
An amount of protons an element contains
What is an element?
Pure substance containing only of atoms with the Same amount of protons
What is a mass number?
Total number of protons/neutrons in a nucleus
What is a periodic table?
All elements known in a table based on their chemical properties
What is a radioisotope ?
Radioactive isotope
What is radioactive decay?
The spontaneous emission of energy when their nucleus breaks down
What is a tracer?
Any molecule with a detectable substance attached
What is a shell model?
Used to check an atom for vacancies
What is an ion?
Atom with a different amount of electrons and protons
What is electro negativity?
Measure of an atoms ability to pull electrons from other atoms
What is a chemical bond?
Attractive force that arises between two atoms when their electrons interact.
What is a molecule?
Formation when two or more atoms of the same or different elements join in chemical bonds
What are compounds?
Molecules that consist of two or more different elements in proportions that do not vary
What is a mixture?
Two or more substances intermingle. Does not bond
What is a covalent bond?
Two atoms sharing a pair of electrons
What is non polar?
Atoms participating in bond share electrons equally
What is polar?
Atoms participating in a bond do not share electrons equally
What is polarity?
Separation of charge into distinct positive and negative regions
What is a hydrogen bond?
Weak attraction between a highly electronegative atom and a hydrogen atom
What is a solvent?
Liquid that can dissolve other substances
What is a solute?
The substance being dissolved
What does hydrophilic mean?
Polar molecules that are water loving
What does hydrophobic mean?
Water dreading substances ie.oils
What is temperature?
Way to measure energy of a molecular motion (vibration)
What is evaporation?
Molecules move faster and individual molecules at the waters surface escape into the air
What is cohesion ?
Molecules resist separating from one another
What is ph?
The measure of the amount of hydrogen ions in a solution
What are acids?
They donate hydrogen ions as they dissolve in water
What do bases do?
They accept hydrogen atoms
What is a salt?
Something that dissolves easily in water and releases ions other than h+ and oh-
What is a buffer system ?
Weak acid or base and it’s salt that can keep the ph of a solution stable
What is a functional group?
A cluster of atoms covalently bonded to a carbon atom of an organic molecule
What is metabolism?
Activities by which cells acquire and use energy as they construct, rearrange, and split organic compounds.
What is condensation ?
Two molecules covalently bonded into a larger one
What is a monomer?
Molecule that is used to build larger molecules that are the structural and functional parts of cells
What is a polymer?
Large chains of monomers
What is cleavage?
When a molecule splits into two smaller ones. Hydrolysis is an example
What is a functional group transfer?
When a functional group is transferred from one molecule to another
What is electron transfer ?
When electrons are transferred from one molecule to another
What is rearrangement?
Juggling of covalent bonds converts one organic compound into another
What are carbohydrates?
Organic compounds that consist of carbon, hydrogen and oxygen in a 1:2:1 ratio
What are lipids?
Fatty, oily, or waxy organic compounds that are insoluble in water
What are fatty acids?
Simple organic compounds that have a carboxyl group joined to a backbone of four to thirty six carbon atoms
What are fats?
Fats are lipids with one, two, or three fatty acids that dangle like tails from a small alcohol called glycerol
What are triglycerides?
Fats with three fatty acid tails linked to the glycerol
What are phospholipids ?
Have a polar head with a phosphate in it and two non polar fatty acid tails
What are waxes?
Complex, varying mixtures of lipids with long fatty acid tails bonded to long chain alcohols or carbon rings
What are steroids?
Lipids with a rigid backbone of four carbon rings and no fatty acid tails
What is a protein?
Organic compound composed of one or more chains of amino acids
What are Polypeptides ?
Bonded amino acids in chains
What is to denature?
To have the shape unravel and to no longer function
What is ATP?
A nucleotide called adenosine triphosphate
What are Nucleic acids?
Polymers - chains of nucleotides in which the sugar of one nucleotide is joined to the phosphate group of the next
What is RNA?
Ribonucleic acid
What is DNA?
Deoxyribonucleic acid
What are monosaccharides?
Simple sugars
What are oligosaccharides?
Short chain carbohydrates
What are polysaccharides?
Complex carbohydrates
What are glycerides?
Glycerol backbone with one,two or three fatty acid tails ie. triglycerides
What are mostly fiberous proteins?
Long strands or sheets of polypeptide chains ; often strong and water insoluble
What are mostly globular proteins?
One or more polypeptide chains folded into globular shapes; many roles in cell activities
What four generalizations make up cell theory?
- Every living organism consists of one or more cells 2. The cell is the structural and functional unit of all organisms. A cell is the smallest unit of life, individually alive even as part of a multicelled organism3. All living cells come from a division of other pre-existing cells 4. Cells contain hereditary material which they pass on to their offspring during division
What is a cell?
A cell is the smallest unit that shows the properties of life
What is a eukaryotic cell?
A cell containing a nucleus
What is a prokaryotic cell?
A cell without a nucleus
What is a plasma membrane?
Cells outer membrane
What is a nucleus?
Double membraned sac holding a eukaryotic cells DNA
In prokaryotic cells where is the DNA found?
In a region of cytoplasm called the nucleoid region
What is a cytoplasm?
A semi fluid mixture of water, sugars, ions, and proteins between the plasma membrane and the region of DNA
What are ribosomes?
Structures on which proteins are built and suspended in cytoplasm
What is surface to volume ratio?
A physical relationship
What is a lipid bilayer?
The structural foundation of all cell membranes
What is a cell wall?
A rigid wall surrounding the plasma membrane of nearly all prokaryotes.
What is flagella?
Slender cellular structures used for motion
What is a pili?
Protein filaments that helps cells cling to or move across surfaces
What are biofilms?
Communial living arrangements in which single celled organisms live in shared mass of slime
What does the endoplasmic reticulum do?
Routes and modifies new polypeptide chains and synthesizes lipids
What does a Golgi body do?
Modifies new polypeptide chains and sorts and ships proteins and lipids
What do vesicles do?
Transport, store and digest substances in a cell
What do mitochondrion do?
Make ATP by sugar breakdown
What do chloroplast do?
Make sugars in plants and some Protists
What does a lysosome do?
Intracellular digestion
What does peroxisome do?
Inactivates toxins
What does a vacuole do?
Stores things
What is an organelle?
Structure that carries out a specialized function in a cell
What does a ribosome do?
Assembles polypeptide chains
What does a centriole do?
Is an anchor for cytoskeleton
What is a nuclear envelope?
The membrane of a nucleus
What is a nucleoplasm?
A viscous fluid similar to cytoplasm
What is a nucleolus?
A dense irregularly shaped region where subunits of ribosomes are assembled from proteins and RNA
What is chromatin?
Name for all of the DNA together with its associate proteins in the nucleus
What is a chromosome?
Each molecule of DNA together with it’s many attached proteins
What is the endomembrane system?
Series of interacting organelles between the nucleus and the plasma membrane
What is endoplasmic reticulum ?
Extension of the nuclear envelope
What are peroxisomes?
Containing enzymes that digest fatty acids and amino acids
What are vacuoles?
They isolate and dispose of waste, debris or toxic materials
What is a Golgi body
Attach phosphate groups or sugars and cleave certain polypeptide chains
What are lysosomes?
Vesicles that contain powerful digestive enzymes
What is a mitochondrion?
Type of organelle that specializes in making ATP
What are plastids ?
Membrane enclosed organelles that function in photosynthesis or storage in plants and algal cells
What are chloroplasts?
Organelles that are specialiZed for photosynthesis
What is a central vacuole?
An area where amino acids, sugars, ions, wastes, and toxins accumulate
What is a primary wall?
Plasma membrane cemented together by pectin and is then covered in cellulose
What is a secondary wall?
The secretion of material onto the primary walls inner surface forms the secondary wall
What is lignin?
A complex polymer of alcohols that makes up as much as 25% of the secondary wall of cells in older stems and roots
What is an extra cellular matrix?
Non living complex mixture of fiberous proteins and polysaccharides is secreted by cells and varies with the type of tissue.
What are cell junctions?
Structures that connect cells to other cells and to the environment
What are microtubules?
Long, hollow cylinders that consist of subunits of the protein tubulin
What are microfilaments?
Fibers that consist primarily of subunits of the globular protein actin
What is a cell cortex?
A reinforcing mesh under the plasma membrane
What are intermediate filaments ?
Stable parts of a cells cytoskeleton that strengthen and maintain cell and tissue structures
What are motor proteins?
Accessory proteins that move cell parts in a sustained direction when they are repeatedly energized by ATP
What are eukaryotic flagella and cilia?
Whiplike structures that propel cells through fluid
What is a centriole?
Barrel shaped organelle which remains below the finished area as a basal body
What are psuedopods?
False feet
What is ATP?
The energy currency of the cell
What does DNA tell organisms to do?
To grow, develop and reproduce using information in their DNA
What molecules are cells composed of?
Carbohydrates - sugarsLipids - fatsProteinsNucleic acids - DNA and RNA
Compare life’s three domains
- Bacteria - single celled , prokaryotic2. Archaea - single celled, prokaryotic. Evolutionarily closer to eukaryotes3. Eukarya - eukaryotic cell. Both single celled and multicelled
Name the six kingdoms
- Bacteria2. Archaea3. Protists4. Plants5. Fungi6. Animals
What happens to adaptive traits over generations?
They tend to become more common in a population and less adaptive forms of traits become less common
Give an example of artificial selection?
Dog breeds
What is a vestigial structures and what is it an example of?
It is a structure that loses it’s original function and becomes something else. Ie hair of a chimp standing up to show fear ➡️ goosebumps on a human
What is science limited to?
Science is limited to that which is observed
Give an example of an observation
People get cancer
Give an example of a hypothesis
Smoking cigarettes may cause cancer
What is probability?
The measure expressed as a percentage of the chance that a particular outcome will occur
What does statistically significant mean?
It refers to a result that is statistically unlikely to have courses by chance
What atoms are life’s chemical basis?
Protons, neutrons , electrons
Why do electrons matter?
Whether an atom will interact with other atoms depends on how many electrons it has
How to electrons move around the nuclei?
They move in orbitals
What are the three most common types of bonds?
Ionic, covalent and hydrogen
What is an ionic bond?
Weak bond. Ions stay together because of mutual attraction of opposite charges, have a large difference in electronegativity
What is a covalent bond?
Two atoms with similar electronegativity and unpaired electrons sharing a pair of electrons. Stronger than ionic bond. Can share one, two or three pairs of electrons
What are the two types of covalent bonds and give a short explanation
- Non polar covalent bond : share electrons equally. Formed between atoms with identical electronegativity2. Polar covalent bond :Atoms with different electronegativity do not share electrons equally. One atom is more neg other is more pos
What is polarity?
Separation of charge into distinct positive and negative regions in a polar covalent molecule
What is a hydrogen bond
A weak attraction between a highly electronegative atom and a hydrogen atom taking part in a seperate polar covalent bond. Not a chemical bond. Not a molecule. Stabilizes structures of proteins and DNA
Where did life originate ?
Life originated in water.
Does water have a charge?
No water does not have a charge
Is a water molecule polar or non polar? And why
Water molecule is polar because oxygen atom is slightly negative and hydrogen atom is slightly positive
Are polar molecules hydrophobic or hydrophilic?
Hydrophilic
Are non polar molecules hydrophilic or hydrophobic?
They’re hydrophobic
Are nonpolar molecules able to be dissolved by water?
No, only polar molecules
What is specific heat?
Heat needed to raise temp by 1 degree
What is cohesion?
When molecules resist separating from each other
Why don’t marine life forms freeze in the winter?
Because ice is less dense than water and freezes ontop of the water
What do trans fats do to the body?
Raise levels of cholesterol in our blood and directly alter blood vessel function
What are trans fats?
Partially hydrogenated vegetable oils formed by a chemical hydrogenation process. Double bond
Bonds can be both…
Cis or trans
What molecules are considered organic molecules?
Carbohydrates, lipids , proteins and Nucleic acids
Give four properties of organic molecules
- Always contain c and h2. Always covalently bonded3. May be quite large4. Often associated with living organisms
Give four properties of inorganic molecules
- Usually contain metals and non metals2. Usually ionic bonds 3. Relatively smaller4. Often associated with non living organisms
What are carbon ring structures represented as and what do they imply?
Represented as polygons and carbon atoms are implied
Describe the hydroxyl group
PolarFound in alcoholsFound in sugars and amino acids
Describe the methyl group
NonpolarFound mainly in fatty acids
Describe the carbonyl group
Found in sugars, amino acids and nucleotide bases
Describe the carboxyl group
Found in amino acids and fatty acidsHighly polarHas ability to donate h+ hence acid
Describe the amine group
Found in amino acidsGives organic molecule ability to absorb h+ hence weak base
Describe the phosphate group
Found in ATP, phospholipids, DNA, RNA Water soluble
Describe sulfhydryl group
Sulphur is highly electronegativeStrong factor in giving shape by forming disulfide bridges
What does the metabolism require?
Enzymes
What are the five categories of reactions
- Functional group transfer2. Electron transfer3. Rearrangement4. Condensation5. Cleavage
What do carbohydrates contain?
A carbonyl functional groupSeveral hydroxyl groupsMany c-h bonds
What are the four types of carbohydrates in living systems?
Monosaccharides DisaccharidesOligosaccharidesPolysaccharides
What is a monosaccharide called if it has 3 carbons?
Trioses : Ex. Glyceraldehyde
What are monosaccharides called if they have 5 carbons?
Pentoses:Ex. Deoxyribose, ribose
What are monosaccharides called if they have 6 carbons?
HexosesEx. Glucose, galactose, fructose
What disaccharide is formed when glucose is bonded with fructose?
Sucrose
What disaccharide is created when glucose is bonded with glucose?
Maltose
What disaccharide is formed when glucose is bonded with galactose?
Lactose
What are the four most common polysaccharides?
Cellulose, starch, glycogen and chitin
What is cellulose used for?
In plant cell walls
What is chitin used for?
Nitrogen containing groups attached to glucose monomers in insects and fungal cell walls
What is a peptidoglycan used for?
Forms a mesh like layer outside the plasma membrane of bacteria, forming the cell wall
What is starch used for?
In plants, branched chains
What is glycogen used for?
In animals is stored in muscle and liver cells
Describe saturated fatty acids
No double bonds between carbons and is saturated with hydrogen atoms
Describe both types of unsaturated fatty acids
Some double bonds in carbon chainMonounsaturated: one double bondPolyunsaturated: more than one
What is eater linkage?
The connection between a head and a fatty acid tail
What does amphipathic mean?
Have both hydrophilic and hydrophobic properties
What is a polypeptide?
Chain of amino acids bonded together by peptide bonds in a condensation reaction between the amine group of one amino acid and the carboxyl group of another amino acid
List the four levels of protein structure
PrimarySecondaryTertiaryQuaternary
What is a primary structure (protein)
Unique amino acid sequence of a protein
What is a secondary structure ?(protein)
The polypeptide chain folds and forms hydrogen bonds between amino acids
What is a tertiary structure (protein)?
Secondary structure is compacted into structurally stable units called domainsForms a functional protein
Describe a quaternary structure(protein)?
Some proteins consist of two or more folded polypeptide Chains in close association
What are prion diseases caused by?
Caused by misfiled proteins
What do nucleotides consist of?
One or more phosphate groupsA pentose sugarA nitrogenous base
In DNA a,t,c,g pairs with what?
A with TG with C
What is the formula for image magnification ?
Objective power x ocular power
What is the ocular lens?
Lenses you look through
What is the objective lens?
The lens that is closest to the object
What is the revolving nose piece?
It holds the objectives
What is the coarse focus knob?
Raises and lowers the stage allowing you to focus the image
What is the fine focus knob?
Raises the stage by tiny amounts and brings the image into sharp focus
What is the stage?
Holds the glass microscope slide containing the specimen
What is the light source
Built into the microscope
What is the arm?
Let’s you carry the microscope with one hand, while the other holds the microscope underneath
What is the iris diaphragm?
Controls the amount of light entering the lens system
What is the substage condenser?
Focuses light on the subject
What objective is the nosepiece supposed to be on when you remove a slide?
4x
What is the objective power of the scanning objective?
4x
What is the objective power of a medium power objective?
10x
What is the objective power for a high power objective?
40x
What is the objective power of an oil immersion objective?
100x
What microscope allows for the largest image magnification?
Compound
What happens to the field of view as you change it from low to high magnification!
The higher magnification the smaller the field of view
What is the body tube
The body tube is the tube part of the oculars
What is the shape of cocci?
Small spheres
What is the bacilli shaped as?
Rod shaped
What is spirilla shaped like?
Corkscrew shaped
What color is gram positive bacteria?
Violet
What color is gram negative bacteria?
Pink/red
What is the formula for Magnification of a drawing?
Drawing size (um)________________Measured cell size (um)
How do you convert from mm to um?
Multiply by 1000. Ex: 2.7mm x 1000 = 2700um
How do you measure the length of something?
Put it on leftmost side and see how much space is takes up and multiply it by how big the field diameter is.
How do you calculate field diameter?
4(x) x 5mm = 10(next objective) x fd10xFd10x = 4 x 5mm /10x = 2mm
How do you calculate grams of solute?
Molecular weight (grams/mole) x volume (litre) x molarity (moles/litre)
What is the formula for preparing dilutions?
M1v1 = m2v2Final m solution x final liter Divided by stock solution
What is the law of diffusion?
Molecules move from areas of higher chemical potential to areas of lower chemical potential
What is chemical potential?
Measure of free energy available to do the work of moving a mole of molecules from one location to another
Give an example of a time chemical potential is used
To move a molecule through a cell membrane
The relationship between concentration of dissolved substance and chemical potential is what?
Proportional
Molecules move from areas of _____ concentration to areas of _____ concentration
High concentration to Low concentration
What is osmosis?
Movement of water molecules from regions if higher water potential to regions of lower water potential across a selectively permeable membrane
What is water potential?
Measure of the chemical potential of water molecules
What is water potential affected by?
Amount of other substances dissolved in water
The ______ the concentration of a dissolved solute in water, the _____ the water potential
Greater, lower
What is the water potential of pure water?
0
When solute is added to pure water, does the water potential become negative or positive
Negative
Water moves across membranes toward areas with ______ concentration of solutes, where the water potential is ______
Higher, lower
Give two examples of passive transport
DiffusionOsmosis
What does passive transport mean?
Molecules are moving down concentration or free energy gradients
What is active transport?
Moving a molecule against a gradient and requiring energy
What movement is exhibited in Brownian movement?
Jiggling
Can you see water molecules in a microscope ?
No
Would an increase in temperature increAse or decrease the rate of Brownian movement?
Increase
Why are molecules in liquids in constant movement?
Due to their kenetic energy
What is the rate of diffusion controlled by? (4 things)
The size of the diffusing particleThe temperatureThe viscosity of the mediumThe concentration gradient
Does the net movement of molecules slow down as equilibrium is reached? Why?
Yes, because the concentration gradient is smaller
What can you say about the chemical potential of pigment molecules at different distances from the center of a spreading pigment spot
At the center the chemical potential is higher, away from the center is lower
How is chemical potential of pigment molecules related to their rate of movement?
As the chemical potential decreases, the rate of movement slows down.
Does net diffusion eventually come to an end? Why?
Yes, because equilibrium was reached
What type of membrane does a cell membrane have?
Semi permeable
What molecules can move freely through the cell membrane?
Hydrophobic solute molecules, water, small polar uncharged molecules
Solutes diffusing through a selectively permeable membrane diffuse from an area of ______ chemical potential to an area of _____ chemical potential
High,Lower
What happens it two solutions diffusing contain equal concentrations of solute?
Their chemical potentials are equal and no net movement of particles occurs
In a laboratory how can molecules of different sizes be separated?
Molecules of different sizes can be separated by dialysis using artificial semipermeable membranes
How do living membranes select molecules of differing sizes to go through them?
They change their pore size by altering lipid and protein content
What can you say about the effects of molecular size on the diffusion of molecules across a semi permeable membrane?
If the molecule is very big then it won’t go through the membrane
What is an isosmotic/isotonic medium?
Medium that has the same concentration of osmotically active particles as are present inside the cell
What is a hyperosmotic/hypertonic medium?
Medium that has higher concentration of osmotically active particles that forces a cell to lose water by osmosis to the medium
What is plasmolysis and what does it occur in?
Plasmolysis is when a cell becomes dehydrated and shrinks and it occurs in plants
What is crenation and what does it occur in?
Crenation is when a cell becomes dehydrated and shrinks. It occurs in red blood cells
What is a hypoosmotic/hypotonic medium?
Medium that has a lower concentration of osmotically active particles.
What is turgidity and in what does it occur?
Turgidity is when a cell gains water by osmosis and swells
What is hemolysis? And in what does it occur?
Hemolysis is when a cell gains water and swells and can continue to gain water until it bursts. It occurs in red blood cells
What does lysed mean?
The cell burst
What is the relationship between the increase in mass and the molarity of sucrose in the dialysis bag?
There’s a proportional relationship
If two solutions are isotonic to each other, how do their solute concentrations compare?
They are the same
What are enzymes?
Proteins that control reactions in cells
What are biological catalysts?
Accelerate metabolic reactions to a biologically useful rate by lowering activation energy.
Enzymes are ______ proteins
Globular
Enzymes folds create the _____ site
Active
Each amino acid has one specific _______
Substrate
What is the alteration of the active site called?
An induced fit
Any structural change in an enzyme will __________ it by altering its ________ and _______ the reaction rate
DenatureActive site Slowing down/stopping
What is an inhibitor?
A molecule that binds to the active site preventing a substrate from bonding and prevents chemical reactions
Enzymes function best at optimal _______ and ______
Temperature pH
What enzyme is found in living tissues?
Catalase
What does the enzyme catalase do?
Breaks down hydrogen peroxide in cells
What is hydrogen peroxide broken down into?
Oxygen and water
The presence/absence of what gas will determine if a reaction is taking place
O2
What is the enzyme responsible for the browning process of fruits?
Catecholase
What is the substrate of catecholase?
Catechol
When does the browning reaction begin?
When the enzyme and substrate are brought together by cell damage in the presence of oxygen.
Why does oxygen start the browning process in fruit? What molecule does it form?
Oxygen promotes the exchange of electrons and pulls electrons from catechole which forms benzoquinone.
What does heat do to an enzymatic reaction?
Denatures the protein and decreases/stops reaction
Explain what happens when a protein is denatured
It loses shape, substrate can no longer go in it, no more active area = no rx
What is solid milk called?
Curd
What is liquid part of milk called?
Whey
What enzyme is required to produce cheese curd?
Rennin
What is the major protein in milk?
Casein
What does rennin do to casein?
Converts it to paracasein
What does para casein do?
Clots or curds the milk.
What is velocity?
Rate of rx
Why is there no increase in reaction rate once the saturation level of the substrate is reached?
All enzymes activation sites are occupied so no further substrate can be used
Does an increase in enzyme concentration influence the mass of curd produced?
Yes the more concentrated the more curd produced
What is an endergonic reaction?
A rx that requires a net energy input to proceed
What is an exergonic reaction?
A reaction that ends with a net release of energy
What are the three key players in a chemical reaction
Reaction, reactant and product
What is the role of etc?
Consists of enzymes and other molecules that accept or give up electrons one after another, at a cell membrane
In the etc: electrons enter at _____ energy level ➡️ leave cycle with ______ energy level
High Low
In terms of etc: what is the role of coenzymes in etc?
They deliver electrons to etc in photosynthesis and aerobic respiration
Energy released during the etc cycle does what?
Drives the synthesis of ATP
What are enzymes?
Proteins, one specific substrate, metabolic catalyst
What is a substrate?
The specific reactant acted upon by an enzyme
What is an active site?
Location on enzyme molecule where substrates bind and reaction proceeds
What is the overall reaction for photosynthesis ?
Co2+h20+sunlight ➡️ c6h12o2 + o2 + h2o
What happens in light dependent reactions ?
Light energy is transferred to ATP and nadph. Water molecules split and release o2
Where do light dependent reactions occur?
In thylakoids
What happens in a light independent reaction?
ATP and nadph (from previous stage) is used to convert co2 to glucose and then to sucrose, starch and cellulose.
Where do light independent reactions occur?
Occur in stroma
What is the role of pigment in photosynthesis?
The pigment captures the light energy necessary for photosynthesis
Who uses the anaerobic metabolic pathway?
Prokaryotes, Protists and muscle cells
Who uses the aerobic metabolic pathway?
Eukaryotic cells
What are the two mitochondrial membranes?
Outer and inner
What is it called to be between two mitochondrial membranes?
Outer compartment
Where does the second stage of aerobic respiration take place?
The inner compartment
What are the two steps that glycolysis is divided into?
ATP requiring steps and ATP generating steps
What does the ATP requiring step of glycolysis involve?
phosphorylation
What does the ATP generating step of glycolysis involve?
1 fructose and 6 bisphosphate is cleaved into 2 pyruvates
What is the net result for glycolysis?
2 net ATP 2 Nadh2 pyruvates
Describe what happens in the Krebs cycle?
Break down 1 acetyl coA into 2 co23 Nadh and 1 fadh2 are formed2 ATP is formed and regenerates acetyl coA
Where does electron transfer happen?
Inner mitochondrial membrane
What happens in the electron transfer phosphorylation?
Attaches phosphate group to ADP to form ATP
How many net ATP does glycolysis yield?
2 ATP
How many net ATP does Krebs cycle yield?
2 ATP
How many net ATP does the electron transfer yield?
32 ATP
What are the two fermentation pathways?
Alcoholic fermentation and lactate fermentation
What happens in alcoholic fermentation?
Pyruvates is split into acetaldehyde and co2. Acetaldehyde receives electrons and hydrogen from Nadh, forming nad+ and ethanol
What happens in lactate fermentation?
Pyruvate receives electrons and hydrogen from Nadh, forming nad+ and lactate
How are fats used for energy?
Enzymes cleave fats into glycerol and fatty acids when glucose levels fall
What metabolic cycle does glycerol enter once cleaved from fat?
Glycolysis
What metabolic cycle do fatty acids enter once cleaved from fat?
Krebs cycle
How are proteins used for energy?
Enzymes split dietary proteins into amino acids which enter the bloodstream and are used to build proteins or other molecules
What is mitosis?
Growth and replacement of dead or worn out cells, tissue repair
Where does mitosis occur ?
Somatic cells
What is meiosis?
The formation of gametes
Where does meiosis occur?
Germ cells
Describe the g1 phase of interphase:
Uncondensed, no sister
Describe the s phase from interphase:
Uncondensed but duplicated
Describe the g2 phase from interphase:
Condensed and duplicated
Describe prophase
Condense, nuclear membrane breaks down, centrioles move to opposite poles
Describe metaphase:
Chromosomes align between poles, chromosomes condensed
Describe anaphase
Sister chromatids seperate to opposite poles, each chromatid is now a seperate chromosome
Describe telophase
Chromosomes decondense. Nuclear envelope reforms around 2 clusters of chromosomes
Describe cytokinesis in plants
Cell plate formation, cellulose accumulates, thickens, forms a wall
Describe cytokinesis in animals
Cleavage furrow formation ➡️ cytoplasm pinches in two
What are the 5 functions of a cell membrane?
SemipermeableHelps vesicles formSeparates contents of cell from surroundings Controls in/out movement through protein channelsInteracts with outside environment
What is a passive transporter?
Allow small molecules through a membrane
What is the function of an active transporter?
goes against a concentration gradient, requires ATP
What is the function of a receptor?
Initiate change in cells activity by responding to an outside signal
What is the function of a cell adhesion molecule?
Helps cell stick to one another
What is the function of recognition proteins?
Identify cells as self
What is the function of an enzyme?
Speed up rx
What is a concentration gradient and from what to what do molecules move to?
Difference in concentration between two adjacent regions. Moves from high ➡️ low
What is diffusion?
A substance diffuses across a lipid bilayer
What is endocytosis
Vesicle movement brings substances in bulk into the cell
What is exocytosis
Vesicle movement ejects substances in bulk from cell
What is osmosis?
High water potential ➡️ low water potential
What does isotonic mean?
Same concentration inside and outside
What does hypertonic mean?
More concentration outside cell
What does hypotonic mean?
More concentration inside cell
What does asexual reproduction produce
Genetically identical copies of a parent
What does sexual reproduction do that doesn’t happen in asexual reproduction ?
Introduces a variation in the combinations of traits among offspring
What are genes
Regions in an organisms DNA that encode information about heritable traits
What are alleles?
Different forms of the same gene
What is meiosis
A cytoplasmic division (sexual reproduction)
What does meiosis result in
4 haploid cells
What is a zygote
First cell of a new individual
What happens in meiosis 1
Homologous chromosomes separate
What happens in meiosis 2
Sister chromatid separate
What is the key stage of meiosis 1 and what happens in it
Prophase 1. Synapsis (homologous chromosomes) to form tetrads and pairing at chiasmata. Crossing over.
What is the name of the process of sperm creation
Spermatogenesis
What is the name of the process of egg creation (females)
Oogenesis
What is the result of Spermatogenesis
4 haploid spermatids are formed
What is the result of oogenesis
1 haploid ovum and 3 haploid polar bodies
Describe how sperm are formed
Diploid male sex cell ➡️ (meiosis 1 and cytoplasmic division) primary spermatocyte [diploid] ➡️ (meiosis 2) secondary spermatocytes [haploid] ➡️(cytoplasmic division) spermatids [haploid] ➡️ 4 sperm
Describe how ovum are formed
Oogonium (female sex cell) [diploid] ➡️ (meiosis and cytoplasmic division) primary oocyte [diploid] ➡️ (meiosis 2) first polar body [haploid] and secondary oocyte [haploid] ➡️ three polar bodies [haploid] and one ovum [haploid]
What is fertilization
The fusion of two haploid gametes to result in a diploid zygote
Where does mitosis occur
Somatic cells
Where does meiosis occur
Germ line cells
Meiosis takes a cell that’s ________ and makes it _________
Diploid, haploid
What is a spermatozoan
A mature sperm.
Describe a spermatozoan
Head with DNA and enzyme cap. Mid piece with mitochondria. Flagellum for movement.
Who did the pea plant experiment
Gregor Mendel
Describe why the garden pea was a good model for genetics studies
True breeding Both self and cross fertilization possible Short generation time Easy to work with
What is a mutation
A permanent change in a gene
What is a true breeding lineage
Offspring inherit identical alleles for a trait
What is a hybrid
Has non identical alleles for a trait
What does heterozygous mean
Non indentical alleles of a gene
What does homozygous mean
Identical alleles of a gene
What does a dominant allele do ?
Masks the effect of a recessive allele paired with it
Capital letters signify what
Homozygous dominant
Lower case letters signify what
Homozygous recessive
What is a gene called if it is Aa
Heterozygous
What is gene expression
The process by which information in a gene is converted to a structural or functional part of a cell or body
What is a genotype
Particular alleles an individual carries ie. Ww
What’s a phenotype?
An individual’s observable traits Ie. widows peak
What does P stand for
Parents
What does F stand for
Filial (offspring)
What does F1 stand for
First generation offspring of parents
What does F2 stand for
Second generation offspring of parents
What are monohybrid experiments
Crosses that check for a dominance relationship between two alleles at a single locus
What is a locus
A location
Give an example of a cross between homozygous individuals
AA x aa
Give an example of a cross between heterozygous individuals
Aa x Aa
What is probability
A measure of the chance that a particular outcome will occur
What is a Punnett square
A grid used to calculate the probability of genotypes and phenotypes in offspring
What is Mendels law of segregation
Two genes of each pair seperate during meiosis and end up in different gametes
What is a test cross
A method of determining if an individual is heterozygous or homozygous dominate
How do you perform a test cross
Individual of an unknown genotype is crossed with one that is homozygous recessive Ie. AA x aa or Aa x aa
How many traits do dihybrid experiments involve
2
What is a dihybrid experiments
Tests for dominance relationships between alleles at two loci
What is Mendels law of independent assortment
Many genes are sorted into gametes independently of other genes
What is an incomplete dominance
Intermediate phenotype (what you see ) ie. red + white = pink
What is codominance
Two non identical alleles of a gene are both fully expressed in heterozygotes so neither is dominant or recessive Ie. abo blood group system
What is pleiotropy
One gene product influences two or more traits
What is continuos variation
Traits with a range of small differences
What is a bell curve
When continuos phenotypes are divided into measurable categories and plotted as a bar chart, they form a bell shaped curve
What sex chromosomes do males have
XY
What sex chromosomes do females have
XX
What are autosomes
Chromosomes that are the same in makes and females
What is a karyotype
Micrograph of all metaphase chromosomes in a cell arranged in pairs by size, shape and length
What stops dividing cells at metaphase
Colchicine
Can a dominant autosomal allele be expressed in homozygotes and heterozygotes
Yes
What is progeria
Genetic disorder that results in accelerated aging
What are some x linked recessive disorders
Hemophilia, red-green color blindness and duchenne muscular dystrophy
What are the 4 types of chromosomes structural changes
DuplicationInversionTranslocationDeletion
What is aneuploidy
Too many or too few copies of one chromosome
What is polyploidy
Three or more copies of each chromosome
What is nondisjunction
When a pair of chromosomes fails to seperate properly during mitosis or meiosis
What is monosomy
N-1 gamete
What is trisomy
N + 1 gamete
What is trisomy 21
Down syndrome
What is a pedigree
A standardized chart of genetic connections
What are the three types of inheritance
Autosomal recessiveAutosomal dominantX- linked recessive inheritance
In autosomal recessive does the trait skip a generation
Typically
What is autosomal dominant
Trait appears in every generation. Allele is expressed even in heterozygotes
In an x linked recessive who is the carrier
Females