Biol 211 Midterm 1

Comprehensive vocabulary flashcards covering basic taxonomy, cellular biology, thermodynamics, enzyme kinetics, and membrane transport as outlined in the Biol 211 midterm 1 notes.

Carolus Linnaeus

The first taxonomist during the 1700s.

5-kingdom taxonomic hierarchy

A classification system based on anatomy and nutrition (macroscopic) characteristics

5 kingdoms classification system

The distinct groups including Monera, Protista, Fungi, Plantae, and Animalia.

Monera

Unicellular organisms, no nucleus,

Protista

Unicellular, has nucleus

Fungi

Unicellular or multicellular, has nucleus, saprotropic

Plantae

Multicellular, has nucleus, phototropic

Animalia

Multicellular, has nucleus, heterotrophic

Ribosomes

Structures made from DNA and translated by DNA that are essential to all life.

Nucleotides

used to compare species. similar sequences more closely related species, while different sequences indicate a longer time since divergence.

3 domain classification system

Bacteria, Archaea, and Eukarya based on differences and similarities in molecular information (ribosomal gene specifically)

LUCA

The Last Universal Common Ancestor from which all life originates.

Eukaryotes

Have multiple linear DNA, 80s ribosomes, have a complex endomembrane system

Prokaryotes

Have a single circular DNA, 70s ribosomes, no membrane bound organelles

Bacteria

Unicellular prokaryotes, cell walls of peptidoglycan, small length/radius of 1-5 micrometers

Archaea

Unicellular prokaryotes, cell walls made of pseudopeptidoglycan, small length 1-5 micrometers

Eukarya

Unicellular or multicellular eukaryotes with cell walls made of cellulose, pectin, or chitin, 10x times larger than prokaryotes.

Similarities of Eukaryotes and Prokaryotes

Both cell types possess DNA, ribosomes, plasma membranes, and a cytosome.

Prokaryotic DNA

A single circular DNA molecule present in the nucleoid without a nucleus.

Eukaryotic DNA

Multiple linear DNA molecules that become visible during cell division.

Every time a cell doubles in size

SA increases 4x and volume increases 8x

Endomembrane system

A complex system of membrane-bound structures found in eukaryotes but lacking in prokaryotes.

Doubling a cells size causes the Sa:v ratio to?

decrease by half

Prokaryotic Size Constraints

Prokaryotic cells remain small to maintain an efficient surface area to volume ratio;

Eukaryotic Size Advantage

Eukaryotes can be larger because organelles with their own membranes help increase surface area

Horizontal Gene Transfer

The process where genes are transferred from one species to another by mixing together.

Endosymbiotic theory

The theory that eukaryotic cells formed from a symbiosis among several different prokaryotic organisms, specifically mitochondria and chloroplasts.

Endosymbiosis process

A large prokaryotic host Archaeatook in an anaerobic bacterial endosymbiont. host received energy/ATP while the bacteria received nutrients and protection

Evidence for Endosymbiotic Theory

Mitochondria and chloroplasts are the same size as modern prokaryotes, possess circular double-stranded DNA, and divide by binary fission, have 70s ribosomes

Plant-specific organelles

Structures unique to plant cells including chloroplasts, a central vacuole, and a cell wall made of cellulose.

Phototroph

An organism that obtains its energy from light.

Chemotroph

An organism that obtains its energy from chemicals.

Chemoorganotroph

An organism that obtains its energy from organic sources.

Chemolithotroph

An organism that obtains its energy from inorganic sources.

Autotroph

An organism that obtains its carbon from inorganic sources.

Heterotroph

An organism that obtains its carbon from organic sources.

Chemoorganoheterotroph

An organism that obtains its energy from a organic chemical. It also obtains its carbon from organic sources

Chemoorganoautotroph

An organism that obtains its energy from a organic chemical. It also obtains its carbon from inorganic sources

Chemolithohetrotroph

An organism that obtains its energy from a inorganic chemical. It also obtains its carbon from organic sources

Chemolithoautotroph

An organism that obtains its energy from a inorganic chemical. It also obtains its carbon from inorganic sources

Photoheterotroph

An organism that obtains its energy from light. It also obtains its carbon from organic sources

Photoautotroph

An organism that obtains its energy from light. It also obtains its carbon from inorganic sources

A system is…

Anything of interest

Everything outside the system is the?

Surroundings

Open Systems

Systems exchanges BOTH energy and matter with its surroundings

Isolated system

System that does NOT exchange MATTER or ENERGY with the surroundings

Closed system

A system that exchanges energy with its surroundings but not matter.

Work

Changes that require energy

Energy

Is the ability to cause change

First Law of Thermodynamics

Energy is neither created nor destroyed; it can only change location or form.

Potential Energy

Stored energy, increases the further the e- is from the nucleus.

Kinetic Energy

Energy of change. Energy doing work

Does non polar or polar bonds have more energy and why?

Non polar bonds have more energy because the electron is further from the nucleus.

Non polar covalent bonds

More potential energy, less then 0.4 is non polar. c-c, c-h, h-h

Polar covalent bonds

less potential energy, c-o, h-o

Enthalpy (H)

The sum of all potential and kinetic energy in a system; measured as heat released (-H) heat absorbed (+H)

Exothermic

A reaction where energy is released as heat, the products have less enthalpy than the reactants. with units in kj/mol

Endothermic

A reaction where energy is absorbed as heat, the products have more enthalpy than the reactants. with units in kj/mol

Spontaneous reactions

Reactions that can occur under current conditions; identified by a positive S

Important Current conditions

temperature, pH, atmospheric pressure, and the concentration of reactants and products.

Entropy (S)

A measure of how dispersed the energy of a system and its surroundings are. Energy more dispersed +S, energy less dispersed -S. Units are J/molK

Second Law of Thermodynamics

The total entropy of the universe is always increasing; every energy transfer must increase total entropy.

Total Entropy

Considers both the system and the surrounding entropy. Means that the entropy of the system can decrease if entropy of the surroundings increases to a greater degree

Free energy (G)

A measure of energy in a system that is available to do work. If energy is available-G, if energy is not available +G

In order for work to occur….

The reactants must have more free energy than the products

Exergonic reaction

spontaneous, enough energy available -G, and increased the total entropy of the universe +S. Products have less free energy then the reactants

Endergonic reaction

Nonspontaneous, not enough energy available +G, and not increasing the total entropy of the universe -S. Products have more free energy than the reactants.

Chemical Equilibrium

A state where the rate of the forward and reverse reactions are equal

Standard free energy change (triangle Go)

Free energy measurements determined in a lab under standard conditions, 25•c, 1 atm, concentrations of products and reactants are equal

Metabolic Reactions

Sum of all reactions in a cell

Catabolism

Metabolic reactions that break down complex molecules.

Anabolism

Metabolic reactions that build up complex molecules.

Connected reactions

The product of the first reaction serves as the reactant for the second reaction.

Coupled reactions

A process where the energy released by an exergonic reaction is used to drive an endergonic reaction.

What type of energy do ATP molecules in a cell have

Potential energy and kinetic

How do cells carry out endergonic processes?

Through a series of Exergonic reactions

Proteins

Polymers of amino acids linked into peptides and polypeptides, bonded into 3D structures.

Hydrophobic

Nonpolar covalent bonds, mostly c-c-h

Hydrophilic

Polar covalent bonds, c-o, o-h, n-h, c-n

Amino acids are linked together into…

Peptides

Peptides

Molecules made from amino acids

Polypeptide

A polymer made from 10 or more amino acids

Primary structure

The literal order of amino acids in the polypeptide

Secondary structure

Coiled helices or sheets stabilized by hydrogen bonds along the backbone

Tertiary structure

The overall 3D shape of a protein resulting from interactions between R-groups.

Quaternary structure

A functional protein formed by the combination of two or more polypeptides, such as homotrimers or heterotrimers.

Most biological reactions are slow because…

The bonds in the reactants are stable, we need to destabilize these bonds

Activation Energy (Ea triangle Gstar)

The energy required to destabilize bonds in reactants to start a chemical reaction. Energy needed to get reactants to transition state

Transition State

Bonds are both breaking and forming

Ways to speed up a chemical reaction

Add a caytalyst

Biological Catalysts

Molecules that assists getting reactants to transition state, and decrease Ea to speed up reactions.

How do enzymes reduce Ea?

When the substrate enters an active site the enzyme changes shape and forms a enzyme substrate complex

Induced fit model

the enzyme-substrate complex changes structure to force reactants into the transition state.

The rate of an enzyme reaction depends on…

The concentration of the enzyme and substrate

How do cells control/regulate enzyme kinetics?

The concentration of inhibitors and activators

pH can alter the enzyme function…

Protein changes shape and becomes less active, eventually denatured

Temperature can alter Enzyme function…

Low temp reduces reaction rate, high temp denatures proteins

Reversible Competitive Inhibitor

chemically like substrate, binds to the enzymes active site. Molecule with highest concentration will win the competition

Reversible Noncompetitive Inhibitor

Not chemically like substrate, binds on enzyme NOT ON active site, high concentrations of substrate do not affect the inhibitor from binding to enzyme

Allosteric Activators

Bind to enzyme, changes shape to a more active form