Quizzes from Biology
Glucose is an example of a -lipid -nucleic acid -polysaccharide -monosaccharide -amino acid
monosaccharide
A single proton has what charge
+1
Some characteristics of lipids include: A) They are usually hydrophobic B) They are usually Hydrophilic C) They have a lot of C-H bonds D) A & C E) B & C
A & C
Why is formation of ATP by ATP synthase in the mitochondria known as oxidative phosphorylation? -Oxygen is used to provide the mechanical energy that drives ATP synthase in the mitochondria -ADP combines with oxygen to form ATP -A proton gradient created by the redox reactions of the ETC is used to drive the synthesis of ATP -A phosphate is transferred form an oxygen to ADP to form ATP
A proton gradient created by the redox reactions of the ETC is used to drive the synthesis of ATP
Define Solute
A substance that is dissolved in a solution.
How and where it ATP made in a eukaryotic cell? -ATP is made by an enzyme complex that uses the energy of protons moving down their concentration gradient from the mitochondrial matrix to the cytoplasm to make the ATP -ATP is made in all compartments of the cell in response to endergonic reactions and is used to drive exergonic reactions in the cell. -ATP is only made in the mitochondria in response to chemiosmosis -ATP can be made by direct phosphorylation of ADP in the cytoplasm, and by an enzyme complex that uses the energy from a proton gradient to drive ATP synthesis in the mitochondria. It can also be made in other locations in the cell, depending on the cell type.
ATP can be made by direct phosphorylation of ADP in the cytoplasm, and by an enzyme complex that uses the energy from a proton gradient to drive ATP synthesis in the mitochondria. It can also be made in other locations in the cell, depending on the cell type.
If the inner membrane were leaky (e.g. brown fat) which of the following would decrease? Metabolic Heat ATP yield per glucose molecule Rate of oxygen consumption Rate of CO2 production All of the Above
ATP yield per glucose molecule
In the absence of oxygen, NADH & FADH2 are unable to "unload" electrons at the electron transport chain. How will this affect the other components of cellular respiration? A. This will have no effect on the krebs cycle B. This will have no effect on glycolysis C. the cell will undergo fermentation to make ATP D. krebs cycle will halt due to shortage of NAD+ & FAD E. Both C & D are correct
Both C & D are correct
Water interacts with polar substances like -OH groups but not with nonpolar substances like methyl (-CH3) or ethyl groups (-CH2). Using this information, select the molecules that will easily dissolve in water based on polarity not on size. Check all that apply. CH4 CH3OH CH3 CH3 CH3 CH2 CH2 OH CH3 CH2 CH2 CH2 CH2 CH3
CH3OH & CH3 CH2 CH2 OH
Carbon Dioxide (Co2) is produced during aerobic respiration. Which statement is true? -CO2 brings high energy electrons to the ETC -NADH is used to reduce CO2 to make high energy carbohydrates -The oxygen we breath is a reactant in the formation of CO2 -CO2 is often the product when when organic molecule is oxidized
CO2 is often the product when an organic molecule is oxidized
During oxidative phosphorylation, H+ move down their concentration gradient through the ATP-synthase complex. The movement of H+ during this process can cost accurately be described as Osmosis Simple Diffusion Active Transport Facilitated Diffusion Exocytosis
Facilitated Diffusion
What type of energy is driving the ATP-synthase complex to carry out this reaction: ADP + P --> ATP? -Energy released by electrons -Kinetic energy from the sun -H+ gradient -Active transport -ATP
H+ gradient
What happens to NADH & FADH2 the moment they donate the electron to the electron transport chain? -Immediately reduced to form NAD+ and FAD -Immediately oxidized to form NAD+ and FAD -Immediately degraded (destroyed) -Immediately converted to CO2 -Immediately converted into an amino acid
Immediately oxidized to form NAD+ and FAD
If you awoke and looked out your window and saw a ferret shaking, what might be true about the temperature outside? -Temperatures are moderate and the ferret may be trying to attract a mate. -It is hot and dry, causing the ferret to have decrease its surface are to volume ratio. -It is very hot and the ferret it trying to increase perspiration -It is very cold, and the ferret is shivering to help thermoregulate
It is very cold and the ferret is shivering to help thermoregulate
In the reaction: C3H7O6P + NAD+ ---> C3H8O10P2 + NADH, what happened to the NAD+? -It was reduced -It was lost due to oxidative phosphorylation -It was fermented -It was decarboxylated -It was oxidized
It was reduced
Electrons are brought to the electron transport system by the oxidation of -oxygen -NADH -NADH & FADH2 -ATP -FADH2
NADH & FADH2
One glucose molecule is oxidized by one round of glycolysis & two rounds of the Krebs cycle. Before any ETC activity, most of the energy is contained as -ATP -a H+ gradient -heat -CO2 -NADH & FADH2
NADH & FADH2
Autotrophs produce____ and _____ while, heterotrophs produce _______ and _______ -CO2 & H2O; O2 & Glucose -O2 & H2O; CO2 & Glucose -O2 & Glucose; CO2 & H2O -CO2 & Glucose; O2 & H2O -O2 & H2O; H2O and Glucose
O2 & Glucose; CO2 & H2O
Where do NAD+ and FAD go after they have been oxidized by the electron transport chain? -Return to the krebs cycle to get reduced again -Combine with O2 to become more oxidized -Return to the cytoplasm for exocytosis -They are immediately degraded -Converted into CO2
Return to the krebs cycle to get reduced again
What levels of protein structure would be affected if all hydrogen bonding interactions were prevented? Check all that apply -Primary -Secondary -Tertiary -Quaternary
Secondary, Tertiary, Quaternary
Rate of diffusion is affected by different factors. Of the situations below, predict which one would have the fastest rate of diffusion. -Small molecules that are highly concentrated in cool temperatures. -Small molecules that are highly concentrated in warm temperatures. -Large molecules that are highly concentrated in warm temperatures. -Large molecules that are highly concentrated in cool temperatures.
Small molecules that are highly concentrated in warm temperatures
As electrons move along the electron transport chain, they lose potential energy. How is the energy that is released used by the cell? -The energy is used to pump NAD+ into the cytoplasm so it can be used in glycolysis -The energy is used to pump electrons along the electron transport chain -The energy is used to transport protons agains their concentration gradient -The energy is converted directly into ATP
The energy is used to transport protons agains their concentration gradient
How do membranes form spontaneously? -Enzymes can synthesize lipids directly into a membrane. -Enzymes release energy that is used to link phospholipids together -The hydrophobic polar groups on phospholipids are attracted to each other. -The hydrophobic fatty acid tails on phospholipids are repelled by water. -Lipids bind to each other through hydrophobic bonds.
The hydrophobic fatty acid tails on phospholipids are repelled by water.
What is common to all of the oxidation reduction reactions in the krebs cycle? -They lead to the generation of NADH -They are all decarboxylation reactions -They lead to substrate level phosphorylation of ADP to generate ATP -They are all characterized by a loss of electrons from an organic molecule coupled to the reduction of an electron acceptor
They are all characterized by a loss of electrons from an organic molecule coupled to the reduction of an electron acceptor
A covalent bond forms when -electrons are present in a valence shell -a valence electron is removed from one atom and added to another -a pair of valence electrons is shared between two atoms -one atom attracts electrons more strongly than another atom
a pair of valence electrons is shared between two atoms
Before entering the Krebs cycle, pyruvate is converted to -acetic acid -oxaloacetate -glucose -H20 & CO2 -acetyl CoA
acetyl Co A
Motion ex:
actin and myosin in muscles and some proteins of the cytoskeleton
The electron transport chain is powered by high energy electrons to pump H+ across the inner membrane of the mitochondria (from the matrix to the intermembrane space) the pumping of H+ during this process can most accurately be described as osmosis simple diffusion active transport facilitate diffusion exocytosis
active transport
Pesticides may contain porto uncouplers that allow H+ to freely pass through the mitochondrial membranes. You correctly hypothesize that the ___ -affected mitochondrion will maintain a stronger H+ gradient across the inner-membrane -affected cells will generate significantly less heat -intermembrane space of the affected mitochondrion would become more acidic (pH) -affected cells will yield fewer ATP molecules for every glucose molecule that is completely oxidized -none of the above
affected cells will yield fewer ATP molecules for every glucose molecule that is completely oxidized
If a molecule is moving from an area of low concentration to an area of high concentration it is moving _____ its concentration which is _____ transport
against; active
A sugar is an example of a _________, whereas DNA is a _________. protein; nucleic acid lipid; protein carbohydrate; nucleic acid nucleic acid; lipid
carbohydrate; nucleic acid
A cell using protein-mediated facilitated diffusion is treated with a toxin that prevents conformation change in the membrane protein. What is the most likely outcome? -Carrier protein dysfunction will increase the gradient. -ATP consumption will increase to compensate. -Molecular interference will prevent diffusion. -Only hydrophobic molecules will diffuse.
carrier protein dysfunction will increase the gradient
what type of chemical bond forms during the dehydration synthesis reaction? -covalent -hydrogen -ionic -polymer
covalent
When proteins are denatured, which type of bond is not disturbed? -hydrophobic interactions -covalent bonds -hydrogen bonds -ionic interactions
covalent bonds
Imagine that you place a drop of red food coloring in a glass of water. At first, the red molecules remain concentrated where you placed the drop, but the color eventually spreads throughout the water. This example illustrates -hydrolysis -dehydration synthesis -osmosis -diffusion
diffusion
A hydrophilic substances one that can: -form covalent bonds with hydrogen -dissolve in water -buffer a solution -mix with nonpolar solvents
dissolve in water
A protein that has many hydrophobic R-groups pointing to the outside of the protein would be found -in the lumen of the rough endoplasmic reticulum. -embedded within a membrane. -in the extracellular matrix. -in the cytosol.
embedded within a membrane
The transmembrane protein complexes of the electron transport chain can be found_____ -embedded within the outer-membrane of the mitochondria -embedded within the inner-membrane of the mitochondria -floating around in the inter-membrane space of the mitochondria -floating around in the mitochondrial matrix -embedded within the plasma membrane of the cell
embedded within the inner membrane of the mitochondria
Glucose is taken up by red blood cells by binding to a specific pocket in a membrane protein that then allows it to cross the membrane and move down its concentration gradient. What would be the best explanation of this process? -active transport using a transporter -facilitated diffusion using a transporter -facilitated diffusion using a channel -active transport using a channel
facilitated diffusion using a transporter
If a sequence of amino acids is changed, that will change the ____ of a protein which will change its _______ - structure; bonding -pH; function -pH; folding -folding;function -function;folding
folding; function
Water dissolves salts because it: -is hydrophobic, and salts are also hydrophobic -forms covalent bonds with the atoms of the salt crystal -has partial positive and negative charges -evaporates quickly at room temperature
has partial positive and negative charges
Transport ex:
hemoglobin in red blood cells and protein channels in cell membranes
Define solution
homogeneous mixture
How does ATP participate in coupled reactions? a. Hydrolysis of ATP fuels energy-requiring reactions. b. Synthesis of ATP fuels energy-requiring reactions. c. Hydrolysis of ADP fuels energy-requiring reactions. d. Synthesis of ADP fuels energy-requiring reactions.
hydrolysis of ATP fuels energy requiring reactions
Where in a molecule of ATP is the stored energy that is used by the cell? -within the nitrogenous base, adenine -within the five carbon ribose sugar -in the covalent bonds between the phosphate groups -in the bond between adenine and ribose
in the covalent bonds between the phosphate groups
The movement of protons through ATP synthase occurs from the -Matrix to the inter membrane space -Cytoplasm to the inter membrane space -Intermembrane space to the cytoplasm -Matrix to the cytoplasm -Intermembrane space to the matrix
inter membrane space to the matrix
The H+ gradient is a form of potential energy that drives ATP synthesis in mitochondria. During oxidative phosphorylation, H+ move down their concentration gradient through the ATP-synthase complex from the ______ TO THE ______- - cytoplasm;matrix -matrix;intermembrane space -cytosplasm;intermembrane space -intermembrane space; matrix -intermambrane space; cytoplasm
intermembrane space; matrix
If a bond formed between Na and Cl it would be a ______ bond because the electrons would be ________ -nonpolar covalent; equally shared -nonpolar covalent; unequally shared -polar covalent; unequally shared -ionic; transferred between the atoms hydrogen; equally shared
ionic; transferred between the atoms
A hydrogen bond is distinct from ionic and covalent bonds that it: -is a weak attraction between two molecules -forms only between two hydrogen atoms -is considerably stronger than the other two types of bonds -occurs more commonly in lipids than another types of molecules
is a weak attraction between two molecules
A "naked egg" is a chicken egg surrounded only by a semipermeable membrane. Supposed you placed a naked egg in pure water for 24 hours. what will happen to the egg? -there will be no change -it will swell -it will exert tumor pressure agains the cell wall -it will shrink
it will swell
Under anaerobic conditions, the end product of glycolysis is converted to? -amino acids -lactic acid -hydrochloric acid -CO2 & H20 -acetic acid
lactic acid
The pH in the inter membrane space should be ______ compared to the matrix -more acidic -less acidic -the same
more acidic
_____ are monomers that form polymers called______ nucleotides; nucleic acids amino acids; nucleic acids monoglycerides; triglycerides carbohydrates; monosaccharides
nucleotides; nucleic acids
Example of Adhesion
paper towels readily absorb water water dissolves tables salt (NACL) water dissolves other polar molecules
A concentration gradient is an example of - oxidation-reduction -potential energy -hydrolysis -condensation
potential energy
Defense ex:
proteins in the blood that recognize parasites
An element is determined by the number of
protons
The nucleus of an atom consists of
protons and neutrons
The atomic number of an atom is the number of
protons in the nucleus
The three basic components of an atom are
protons, neutrons, electrons
Regulation ex:
receptors in the pancreas that sense blood glucose levels
Hydrolysis is a chemical reaction where a water molecule is ______ the reaction to ______ a chemical bond. -released from; break -put into; break -released from; form -put into; form
released from; break
The electrons in a non polar covalent bond are: -exchanged between the two molecules -exchanged between the two atoms -shared equally between the two molecules -shared equally between the two atoms -shared unequally between the two atoms
shared equally between the two atoms
Enzyme catalysis ex:
speeds up the reaction: Glucose + ATP → Glucose-6-phosphate + ADP
Support ex:
structural proteins such as keratin and collagen
Example of Cohesion
surface tension water droplets water is liquid rather than gas at room temp
Cytochromes contain a heme group similar to that in hemoglobin. The iron atom (Fe) in the center of the group can be oxidized and reduced. If someone was suffering from iron deficiency anemia, what stage of cellular respiration would be most affected? -The Krebs Cycle -Glycolysis -The electron transport chain -Fermentation
the electron transport chain
As a forensic pathologist, you have just completed an autopsy of a poisoning victim. After a thorough examination, you conclude that the victim died of cyanide poisoning. You know that cyanide binds to the cytochrome oxidase complex, and therefore list the official cause of death as suffocation due to cyanide exposure. However, if you wanted to provide a more technical explanation as to the cause of death, what process was specifically inhibited directly by cyanide? -The formation of water from oxygen -The reduction of NAD+ -ATP synthesis -All proton pumping into the inter membrane space
the formation of water from oxygen
Define Solvent
the substance that dissolves the solute
The nucleotides Adenine, Guanin and Cytosine are found both in DNA & RNA. ______ is found in DNA and _____ is found in RNA -Uracil; Thymine -Thymine; Uracil -Phosphate; Citrate -Amino Acids; Monosaccharides -none of the above
thymine; uracil
What is the purpose of the pumping H+ across the inner membrane into the inter membrane space? -To make more NADH -to lower the acidity in the intermembrane space -to generate a H+ gradient -To make ATP by combining electrons H+ and O2
to generate a H+ gradient
Blood pH is controlled by negative feedback. When your blood pH level becomes too low then____________ -you should crave sour (acidic) beverages -your pancreases will secrete OH- into your intestine -your kidney should remove H+ from the blood -your heart rate should decrease -you will start doing jumping jacks
your kidney should remove H+ from the blood