Biology 1110 Exam 2 Study Questions
What is the source of energy during cellular respiration
ATP
How do we get back to ATP?
ATP goes in, releases energy, ADP exits and will travel to the mitochondria where cellular respiration occurs and ATP is converted back
What is the name of the last protein in the membrane that makes the ATP
ATP synthase
What are the input items of the Calvin cycle
ATP, NAPDH, CO2
Neurons contain a high concentration of potassium ions. How could a neuron acquire even more potassium?
Active transport
What happens in checkpoint G1
Apoptosis can occur if DNA is damaged beyond repair Checks DNA suitability
How do you get rid of the remnants of glucose during cellular respiration
CO2
What are the inputs of photosynthesis?
CO2 and H2O with light
What is the fixation of carbon dioxide stage in the calvin cycle
CO2 is attached to a sugar (ribulose biphosphate RuBP), produces a 6-C intermediate which is unstable and immediately splits into two 3-C molecules
Briefly describe what happens in the Calvin cycle reactions
CO2 is taken up from the atmosphere, using ATP and NADPH (from photo reactions) glucose is produced
Prior to enetering the Krebs cycle, pyruvate loses a _____ and is converted to _______
CO2, acetyl-coA
Carbon fixation is part of which process
Calvin cycle
What are two things true regarding carrier proteins?
Carrier proteins are specific to a single type of molecules, and carrier proteins aid in facilitated transport
What is an example of potential energy?
Chemical energy
Briefly describe what happens in the light reactions
Chlorophyll in the thylakoid membranes capture light energy, water is split, ATP produced and NADPH is produced and moves on
An unduplicated chromsomes has ______ chromatid while a duplicated chromosome has ______ chromatids
1,2
How many chromosomes are present in anaphase
12 UNreplicated chromosomes
Consider a bacterial cell that performs anaerobic respiration. If that bacterial cell had access to 6 molecules of glucose to use, how many ATPs would it be able to produce?
12ATPs
What is the total ATP produced in anaerobic respiration per glucose molecule
2
What is the net ATP gain from glycolysis
2 ATP, 2 NADH, and 2 pyruvates
ALL organisms perform glycolysis which essentially chops a glucose molecule in half to create what
2 molecules of pyruvate
CO2 is removed from a pyruvate to create what
2-C acetyl molecules
If starting with a cell that has a haploid of 10, during mitosis there will be ______ chromosomes at metaphase, _______ chromosomes at anaphase, and ______ chromosomes per daughter cell at telophase.
20, 40, 20
What is the net gain from the ETC
32-34 ATP per glucose molecule
What is the total net of ATP from aerobic respiration
36-38 ATP per glucose molecule
A human cell undergoes mitosis. The resulting cells have ______ chromosomes each
46
A normal human cell that is not dividing will contain _____ chromosomes. These chromosomes will each consist of _______ chromatids
46, 1
All human cells have _______ chromosomes. ______ came from mom and ________ came from dad. Each parent provides _______ unique chromosomes. The other parents gives their version of the same set.
46,23,23,23
What is the net ATP gain from fermentation
4ATP
From the citric acid cycle what moves onto the ETC
6 NADH, 2 FADH2
How many chromosomes are present in metaphase
6 replicated chromosomes
How many chromosomes are present in prophase
6 replicated chromosomes
What is the photosynthesis equation
6CO2 + 12H2O = C6H12O6 +6O2 +6H2O
What are the outputs of the citric acid cycle
6CO2, 2ATP, 6NADH and 2 FADH2
Once ATP is used, what are we left with?
ADP
Light hits the water-splitting photosystem which causes electrons to be excited to a high energy level. That electrons are picked up by an electron acceptor and passed through an electron transport chain where what is made
ATP
What are the two different fermentation options
Lactate and alcohol
What three things do we use ATP for?
Mechanical work (movement), chemical work (reactions such as the synthesis of polymers, and transport work (pumping substances across membranes
What are the two types of cell division for eukaryotic cells
Mitosis and Meiosis
What happens in checkpoint G2
Mitosis will not occur until DNA has replicated Makes sure DNA was accurately replicated Checking sequence- replication is completed
NAD+ is a carrier molecule that removes H+ and e- from molecules to become _____ which transports H+ and e- to the ETC. After the H+ and the e- are dropped off at the ETC, it is recycled to _________
NADH, NAD+
What is the reduction of CO2 and potential for sugar creation stage in the Calvin cycle
NADPH & ATP are used to rearrange each 3-C molecule, produces six G3P molecules and 1 is used by the plant and 5 continue in the cycle
What is Photosystem I
NADPH producing photosystem- electrons from CHL passed to electron acceptor, electron need to be replaced so taken from the ETC, and electron acceptor passes electron NAPP+ who also accepts H+ coming from water
Is the number of chromosomes related to an organisms complexity
NOT AT ALL
What are the three primary categories of ways in which substances can enter cells?
Passive transport, active transport and bulk transport
When is active transport performed?
Performed when cells need to maintain a higher concentration as compared to the outside solution. an example would be the iodine in thyroid cells, solutes and urine formation
What are the three forms of endocytosis?
Phagocytosis, Pinocytosis, and Receptor-mediated endocytosis
Coenzyme A is attached to each acetyl. What does this result in
acetyl-CoA
Which os these statements best explains why your body prefers to perform aerobic respiration as opposed to anaerobic respiration
aerobic respiration produces far more ATP than anaerobic respiration
Who does the process of cellular respiration?
all organisms
Stage of cycle- G1
also known as 1st growth- they physically grow in size and duplicating organelles
Stage of cycle- M
also known as mitotic phase, divide all components into 2 piles and seprate to form 2 daughter cells
Stage of cycle- G0
also known as resting phase, cells do not divide
Stage of cycle- S
also known as synthesis- DNA replication/synthesis
Osmosis always moves water from
an area of low solute concentration to an area of high solute concentration
Why is the aerobic pathway more efficient
anaerobic makes less ATP per glucose molecule
When can the calvin cycle happen
any time of the day
Who performs alcohol fermentation
bacteria and fungi (yeast)
Why does the cirtic acid cycle turn twice
because we have 2 pyruvates
What does glycolysis do
being the breakdown of glucose
Where are the high energy bonds in ATP?
between the 3 phosphates
What are some examples of alcohol fermentation
bread rising, beer/wine
What does the build up of lactic acid contribute to
burning sensations and muscle fatigue and it is also toxic
How is ATP regenerated
by attaching a P to ADP
Now that the plant has made glucose what does it do with it?
can be broken down for energy (cellular respiration), can be stockpiled as starch, or can be made into cellulose and used to maintain/build the cell wall
What happens if checkpoints fail
can result in mutation or disease
What happens in anaphase
cell elongates spindle fibers shorten and pull the sister chromatids apart chromosomes move toward opposite poles
Stage of cycle- G2
cell finishes growing and prepares to divide
During interphase our DNA is in the form of what
chromatin
What happens in telophase
chromosomes arrive at poles spindle fibers breakdown nuclear envelope reappears two daughter nuclei form (during cytokinesis)
What happens in prophase
chromosomes condense and sister chromatids are visible nuclear envelope breaks down and disappears centrosomes produce spindle fibers which attach/capture the chromosomes
What happens in metaphase
chromosomes line up along the metaphase plate (equator of cell) pulled by spindle fibers
what does the preparatory reaction/citric acid cycle do
completes the breakdown of glucose
Where does glycolysis take place
ctyosol/cytoplasm of the cell
Where does anaerobic respiration take place
cytoplasm
How are enzymes inhibited?
decrease substrate, feedback inhibition, competitive inhibition (blocks the action site), and non-competitive inhibition (changes the shape of the active site so the substrate cant bind)
A telomere is involved with what
determining how many times a cell can divide
The difference between diffusion and osmosis is that
diffusion moves small substance from high to low concentration while osmosis moves water from high to low concentration
When are carotenoids visible in a plant?
during the fall, day light shortens and temps decrease then chlorophyll breaks down or stored and then you can see them
How do telomeres relate to cellular aging
each time a cell divides, a little bit of telomere is lost when they are to short- the cell is old and will stop dividing and apoptosis will occur
What is the only part of aerobic respiration that utilizes oxygen
electron transport chain
What is potential energy?
energy an object possesses due to location or spatial arrangement (stored energy)
What is the 2nd law of conservation?
energy cannot be changed from one form to another wihtout a loss of usable energy
What is the 1st law of conservation?
energy cannot be created or destroyed, but it can only be changed from one form to another
What is kinetic energy?
energy of relative motion
How are proteins converted to be used for cellular respiration
excess amino acids deamination ammonia produced and placed into urine and excreted remainder of amino acids enters into glycolysis, preparatory reaction or citric acid cycle
What type of transport across cell membranes involves the use of carrier proteins
facilitated diffusion
How are fats converted to be used for cellular respiration
fats are broken down into the glycerol and fatty acid groups glycerol enters into glycolysis fatty acids are broken down into fragments which enter citric acid cycle as acetyl CoA
What does cytokinesis look like for plant cells
form a cell plate to build a new cell wall which then divides the daughter cells No pinch for plants because of the cell wall
What do you need to start the process of glycolysis
gluce, ATP, NAD+
A cell contains 5% glucose, 20% starch, and 10% protein. The solution surrounding the cell contains 15% glucose, 5% starch, and 5% protein. ___________ will move by diffusion ________ the cell, while water will move _________ the cell due to the effects of osmosis.
glucose, into, into
What are the steps to the aerobic cellular respiration
glycolosis, preparatory reaction/citric acid cycle, electron transport chain
What are the steps to anaerobic cellular respiration
glycolysis, fermentation
When a person receives a blood transfusion, the blood type must be matched for substances that identify the red blood cells. These identifiers on the cell membrane of the cells would be
glycoproteins
Chromatin wrapped around special proteins called what
histomes
The nitrogenous bases of two DNA strands are held together by what kind of bonds
hydrogen
What is apoptosis
if a cell is worn out or the DNA is damaged, instead of replicating it will go into apoptosis (cell death)
Where does recycling occur as long as oxygen is present?
in the ETC
When is the anaerobic pathway used
in the absence of oxygen
where is the concentration of H+ ions the greatest
intermembrane space as compared to the matrix
What does it convery pyruvate to
into ethyl alcohol (drinking alcohol)
Glucose is not directly made in the photo or synthesis reactions of photosynthesis. Where does it come from
is is made from joining 2 G3P molecules that are made during the Calvin cycle
What does selectively permeable mean?
it allows some substances to cross more easily than others, small molecules and ions can freely cross the membrane in both directions, larger molecules or hydrophilic molecules cannot pass freely
Where is there no genetic diversity with binary fission
it essentially involves copying the circular loop of DNA in a parent cell and splitting in half to form two daughter cells
What are three possible reactions when chlorophyll is hit by a photon of light?
it is either absorbed, transmitted or reflected it also excited the electrons to either pass on to an electron acceptor or return to ground state
What happens to the CO2
it is exhaled
What happens every time the electron is passed down the transport chain
it lets off little bits of energy
The splitting of water in photosynthesis is critical to us as animals because
it produces oxygen
Turgor pressure is created by the force of the cell pushing against what
its cell wall
What does lactate fermentation convert pyruvate to
lactic acid
Lactate fermentation is what
lactic acid, our cells perform this during strenous exercise when blood oxygen levels are depleted.
What must be present for light reactions to occur?
light
Describe what happens in the photosystems
light capturing units- what absorbs solar energy
Eukaryotic cells contain DNA in the form of what
linear chromosomes
What function do phospholipids supply?
main component of the membrane, similar in structure to fats
Imagine that you are looking at a cell in the microscope. When you examine the cell, you see that the nucleus is not present and that the chromosomes are condensed and lined up in the center of the cell. What are the possible stages of division in which this cell might be?
metaphase
What is diffusion?
molecules move along a concentration gradient in order to reach equilibrium (high to low)
What is active transport?
movement of a solute against the concentration gradient
Where do the NADH from glycolysis move on to
moves on to the ETC and has the potential to make more energy
When we measure diffusion, we are actually measuring
net molecular movement
What cells are always in the G0 cycle
neurons, skeletal muscle and some white blood cells
Mitosis is done by all cells except
neurons, skeletal muscle, and some white blood cells
How much diversity if achieved in binary fission
none
What is secondary active transport?
one of the two substances is transported in the direction of its concentration gradients, using the energy derived from the transport of such substance down its concentration gradient
What are the plasma membrane malfunctions and applications?
organisms may acquire changes to the structure of their cell membrane via evolutionary adaptation, changes in structure results in change in properties
what are the output items of light reactions
oxygen, ATP (which moves on to the calvin cycle) and NADPH
Suppose an experiment is performed in which plant #1 is supplied with normal CO2 but with water that is labeled with radioactive oxygen atoms so that we can trace their location. Plant #2 is supplied with normal water but with CO2 that contains radioactive oxygen atoms. Each plant is allowed to perform photosynthesis and the oxygen gas and G3P molecules are analyzed for the presence of radioactive oxygen. Which plant will produce radioactive oxygen gas and which plant will produce radioactive G3P?
plant 1 and plant 2
What has both chloroplasts and mitochondria
plant cells
Binary fission is the method of cell division for who
prokaryotes and single-celled eukaryotes (protists)
Mitosis is subdivided into 4 phases, what are they
prophase, metaphase, anaphase, and telophase
What does a telomere do
protects your genetic information
What do you need to start the process of anaerobic respiration
pyruvate
What is the citric acid cycle
rearrangement and breakdown of the remnants of glucose.
Plants can only harvest certain wavelengths of solar energy. The wavelengths that plants can use correspond to what colors
red and blue
What is entropy?
refers to the relative amount of disorganization
What is mitosis used for
reproduction for some organisms (single cell eukaryotes) growth and development and repair- build and maintain our tissues
What does active transport require?
requires transport proteins and the expenditure of energy
Mitosis starts with a ____________ cell and ends with two _________ daughter cells
single parent, identical
Who performs lactate fermentation
some bacteria, fungi and animals
Before the cirtic acid cycle can begin what must happen
some modifications to pyruvate
What does glycolysis mean
sugar splitting
When does osmosis take place?
takes place when the solute molecules are to large to pass through the membrane
A living plant is exposed to water labeled with O18 (a radioactive isotope of oxygen that allows us to trace where it goes) and exposed to sunlight. The O18 will end up in where at the end of photosynthesis?
In released oxygen gas
what is fermentation
the partial degradation of sugars without the use of oxygen
The sodium-potassium pump acts alternately to move sodium and potassium in and out of animal cells by what means
the pump undergoes a change in shape
What is deamination
the removal of the amino group
The primary determining factor as to whether a substance can move across the cell membrane is
the size of the substance
How do enzymes work?
they are specific to their substrate, when they bind to their substrate they make it unstable, once unstable they rearrange chemical bonds
What does a plant do with the glucose they make?
Stockpile it until its needed for energy for cellular activities.
Give an example of a specific sitation where an organism might not be able to perform aerobic respiration
Strenuous exercise, CO poisoning, bacteria without mitochondria whos alternative is fermentation
The most important part of the first three steps of aerobic cellular respiration is
That NAD+ and FAD collect electrons and hydrogen ions for the ETC
The CO2 animals exhale is produced in
The Krebs cycle
What happens to the cell when it is placed in a hypotonic solution?
The cell will gain water and could lyse
What happens to the cell when it is placed in a hypertonic solution?
The cell will lose water or crenate
How do receptor-mediated endocytosis and pinocytosis differ?
Unlike pinocytosis, receptor-mediated endocytosis requires a specific receptor protein to recognize a specific molecule and unlike pinocytosis, receptor-mediated endocytosis allows cells to take in a specific molecule
What kind of light powers photosynthesis?
Visible light
What are the characteristics of an isotonic solution?
What the concentration of dissolved substances in the solution is the same as the concentration of dissolved substances inside the cell
CHL B
Yellow green in color
What does plasmolysis mean
a cell membrane that pulled away from a cell wall due to water loss
What is a chromosome
a cellular structure carrying genetic material
what is the electron transport chain composed of
a collection of molecules embedded within the inner membrane of the mitochondria
What is a chromatid
a copy of a chromosome
What is a photon
a discrete particle with a specific qunatity of energy
What is cytokinesis
a process that physically separates two daughter cells
What is a telomere
a repeating DNA sequence at the ends of a chromosome
What does cytokinesis look like for animal cells
a set of proteins at the equator pinch the cell into two daughter cells
What is mitosis
a single parent cell copies all components and splits to produce 2 daughter cell produces somatic cells- body cells cells are identical- no diversity
What do your cells perfer as fuel for cellular respiration
they prefer glucose as fuel
Your friends are trying their luck at making wine. They have added yeast and glucose to grape juice. A week later they notice that the sugar has been used up by the yeast but there is no alcohol in the mixture. The best explanation is
they should have lowered the oxygen supply to stimulate ethanol production
Cells cant progress from one stage of the cell cucle to the next without passing through special checkpoints. Why is this
this regulation ensures that only needed cells are produced , this can stop/continue based on internal signals
What is a hypotonic solution?
this solution has less solute relative to what it is being compared to. This means it has MORE water relative to what it is being compared to.
What is a hypertonic solution?
this solution has more solute relative to what is is being compared to. This means it has LESS water relateive to what it is being compared to
What is the function of these pigments
to absorb and reflect
A leaf on a plant is phtosynthesizing rapidly, capturing sunlight to perform the photo reactions. Why will this plant also need to perform the synthesis reactions?
to make glucose for the plant
Mitosis is a highly regulated process. Why would it be important to regulate this type of cell division
to prevent over production of cells to not get tumors- any cell that divides uncontrollably is cancerous
Why do plants split water molecules during the photo reactions of photosynthesis?
to provide electrons for the synthesis reactions
Why do our cells go through cellular respiration?
to release energy from the food we consume
What is the purpose of the Krebs cycle
to utilize NAD+ and FAD as much as possible so that there is potential to make ATP in the ETC
What is the function of protein?
transport, enzymatic activity, signal transduction, cell-cell recognition, intercellular joining and attachment of the cytoskeleton to the ECM
What is meiosis
used for reproduction a type of division that reduces the chromosome set of the daughter cells produces gamates- egg and sperm cells creates genetic variation
When do we use bulk transport?
used when items are too big to cross the plasma membrane by other means.
what does the electron transport chain do
uses e- carriers to produce ATP
What is primary active transport?
uses energy in the form of ATP to transport molecules across a membrane against their concentration gradient
Molecules that undergo exocytosis from a cell are enclosed in what
vesicles
What is exocytosis?
vesicles fuse with the plasma membrane in order to release contents outside the cell- molecules EXIT
NAD+ and FAD are essential to the process of cellular respiration. They are formed within our cells from what
B Vitamins
CHL A is what
Biggest proportion and blue green in color
What does the term coupled reaction mean?
Energy required by 1 process is supplied by another process
What happens in checkpoint M
Ensure chromosomes are properly aligned- mitosis stops until they are
Who does photosynthesis benefit?
Every organism on earth
FAD picks up H+ and e- to become ___________ which carried H+ and e- to the ETC; this is a different molecule from _________ but basically has the same job.
FADH2, NAD+
If oxygen is absent what will take the place of recycling
Fermentation
Brain cells and muscle cell lose the ability to perform mitosis at maturity. This means that these cells must be in the ____phase of the cell cycle?
G0
What are the output items of the Calvin cycle
Glucose
What is the end product of photosynthesis?
Glucose
What is needed to perform cellular respiration
Glucose and Oxygen (usually)
What are the products of photosynthesis?
Glucose, Oxygen, Water
What else is creates as a byproduct of this reaction
H2O
How many cell divisions occur for a typical cell
Human cells divide approximately 50-70 times before they enter senescence (old age/ not reproducing)
What happens to the cell when it is placed in an isotonic solution?
Nothing
What happens to oxygen during aerobic cellular respiration?
O2 is used in the ETC to accept elecgtrons and hydrogens to make H2O
At the end of the electron transport chain, the final acceptor of the electrons is ______, which will then produce a molecule of __________
O2, H2O
What is chlorophyll
Primary pigment- majority of the pigment
What are the steps of the preparatory reaction
Pyruvate is oxidized
People who have chronic swelling sometimes use baths with Epsom salts to reduce the swelling. In this case, they use pure water for the bath but then add large amounts of the Epsom salt to the bath water. Explain how this might reduce their swelling. Would the bath water by hypotonic, hypertonic or isotonic to the person?
The high concentration of salts in the bath water would lead to a higher concentration of solutes (and a lower concentration of water) outside the person as compared to inside the person. This would cause water to flow out of the person and into the bath water, reducing swelling. The bath water with Epsom salt is a hypertonic solution.
What is the unique property of phospholipids that makes them well suited to forming the cell membrane?
They contain polar and nonpolar regoins
What is the point of why organisms have to do cellular respiration?
To make ATP
Where do the pyruvates move on
the Citric acid cycle
What is the most important thing that must be copied before a cell divides
the DNA but everything must be copied
A geneticist allows a cell to replicate in the presence of radioactive nucleotides. What will occur?
the DNA in each of the daughter cells would be radioactive
What role do concentration gradients play?
the ETC is powered by a H+ gradient
What is a calorie?
the amount of heat required to raise the temperature of 1 gram of water by 1 degrees Celsius
What is endocytosis?
the cell takes in a substance by forming new vesicles from the plasma membrane- molecules ENTER
The drug DNP destroys the H+ gradient that forms in the ETC. The most likely consequence would be
the cells will be forced to perform fermentation
What is an isotonic solution?
the concentration of solute and water on each side of the membrane is equal
What is facilitated diffusion?
the diffusion of molecules across the membrane with help of transport proteins (channel or carrier proteins)
What is the regeneration of RuBP stage in the Calvin cycle
the five G3P molecules are rearranged into three molecules of RuBP, RuBP can then accept CO2 OR continue on the metabolic pathway to become glucose
What is phagocytosis
the ingestion of bacteria or other material by phagocytes and ameoboid protozoans
What is pinocytosis
the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane
what is receptor-mediated endocytosis
the inward budding of plasma membrane vesicles containing proteins with receptor sites specific to the molecules being absorbed
What is happening in the light that we see
the light we see is reflected, everything else is absorbed
What is ADP
the low energy result when a P is removed from ATP
Where does CoA come from
the matrix of the mitochondria
What is binary fission
the method of asexual reproduction in which the cell divides in half
What is osmosis?
the movement of water molecules across a selectively permeable membrane
What are the input items of light reactions
water and access to sunlight
When two solutions that differ in solute concentration are placed on either side of a semi=permeable membrane and osmosis is allowed to occur, what will happen?
water will move from an area of low solute concentration to an area of high solute concentration
What is Photosystem II
water-splitting photosystem- electrons from CHL passed to electron acceptor, electrons need to be replaced so taken from H2O (water splits) and then electron acceptor passes electrons to the ETC
What function does cholesterol supply?
wedged between phosopholipids, stabilizes position of phospholipids, and maintain optimum fluidity at different temperatures
Where does citric acid cycle take place
within the mitochondrial matrix
What is carotonoid
yellow orange or red in color
