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120 terms

Biology 100

Test 2
STUDY
PLAY
In the chemical reaction A+B-->C, why do A and B join to make C? Does this happen inside or outside of the cell?
Because the cell needs C, and inside the cell
Why do all chemical reactions occur?
B/c high energy tends to move to low energy
In A+B--->C, which side has the higher energy?
C has lower energy than A and B
What is one of the laws of thermodynamics?
Moving from a high energy state to a low energy state
Do products or reactants have lower energy?
Products
What is the hump called in all biological reactions?
Energy of activation
The cell makes ______ called ________
molecules, enzymes
T/F: each reaction has its own unique enzyme
True
What is an enzyme?
A protein
What does the enzyme do?
The enzyme will grab the reactants and tweak them so they are able to fly over the energy of activation.
Where does the enzyme come from?
The cell makes it
Who has control over chemical reactions?
the cell
If a cell needs a lot of a certain product, what will the cell do?
Make lots of enzymes
2H202--->2H20+o2
Hydrogen peroxide
What is hydrogen peroxide?
a poisonous compound made by your body that kills bacteria
How much energy does hydrogen peroxide have?
An enormous amount
How much energy do water and oxygen have?
a fairly low amount
What is catalase?
the enzyme that lowers the energy of activation
Why do many genetic diseases occur?
B/c of faulty enzymes or because the enzymes don't exist
What does the enzyme not do for the chemical reaction?
It does not increase the amount of energy, just tweaks the reactants to drop the energy of activation to nothing so the reactants can change into the product
What do most genes in your DNA make?
enzymes
What holds chromosomes?
the nucleus
What are the 2 roles of chromosomes?
1. to pass gene information to the next generation
2. to control cell activity
Why is it impossible for catalase to stimulate the formation of hydrogen peroxide from water and oxygen?
b/c catalase cannot make energy, just reduces the energy of activation
What are the 6 reasons water is so important?
1. Can't use ATP without water b/c water helps break ATP apart
2. Many molecules and membranes can't function without hydration, and if the membranes aren't hydrates they cannot function and may even leak
3. Because every chemical can dissolve and react with each other, so without water the chemicals would just stick to the side if they couldn't dissolve
4. water is the most excellent temperature buffer, its temp does not change easily and a constant temperature is easier for an organism to stay alive
5. Water has a very low freezing point and very high boiling point, can't have a chemical reaction in a solid (frozen water)
6. Water exists as a liquid across a huge range of temperatures. Water is liquid almost everywhere in the earth
What is the universal solvent?
means that almost everything dissolves in water
What makes up the hydrogen atom?
1 proton and 1 electron
What type of charge do a proton and electron have?
Proton=positive charge. Electron=negative charge.
If there are not enough protons in a cell, what happens?
The cell is not able to do reactions or biological processes
What can too many protons do?
Cause damage and break molecules
What is pH?
The concentration (amount) of protons
What does a pH lower than 7 mean?
That there are a lot more protons in the cell
If there is a cell with a pH of 7 and another with a pH of 5, which has more protons?
The cell with the pH of 5, it has 100 times more the proton concentration. 7-5=2. 10 x 10= 100
What does a pH higher than 7 mean?
That the cell has LESS protons
What is a hydroxyl?
A proton and an OH, exists in water
What is the watery gel like substance in a chloroplast called?
the stroma
What are the special chlorophyll's in a chloroplast?
P680 and P700
What is the OEC?
Oxygen Evolving Concept that replaces the electron for P680
What are the 3 ways a pigment will de-excite?
1. release of heat
2. release of a photon and heat
3. energy migration-make sugar
What makes a plant stressed?
no water or hot temperature
What do smaller wavelengths mean?
that there is more energy
What colors does chlorophyll absorb well? What color does it reflect?
Blue and red, reflects green
What is the wavelength of green?
500
What is the wavelength of flouresence?
700
What color does flourescence appear?
dark red
What does it mean if the chlorophyll in a plant are flourescing?
That's not good for the plant, that's wasting energy
What do plants need to make sugar?
NADPH and ATP
When electrons are flowing in a plant, where do the protons flow from and to?
The protons flow from the stroma to the lumen
Which is more basic/acidic, stroma or lumen?
Stroma is more basic, lumen is more acidic
What is the pH of the stomach?
2
What is the construction of the small intestine like?
Like a tennis court
The pH of tissue is as low as 3 in the morning but 7 in the evening. How did the concentration of protons change during the day?
7-3=4. 10x10x10x10= 10,000
What do many water molecules fall into?
Protons and hydroxyl's
What is the pH of pure water? And what does the concentration of protons equal to in pure water?
7. The concentration of protons is equal to the concentration of hydroxyl's in pure water.
What is pH of 7 called?
neutral
What happens if something is added to pure water, like in a swamp?
Protons would be added to the water and the proton concentration would exceed the hydroxyl concentration so the pH would be LESS than 7, therefore ACIDIC
What happens if protons are removed from pure water?
Then the hydroxyl concentration would increase and the pH would go above 7, called BASIC
What is the typical pH of Kansas tap water?
8
What does a pH of greater than 7 mean?
LESS protons
What pH do living organisms typically have?
around 7
What is the pH of your blood?
somewhere between 7.35-7.45
Do animals tend to be basic or acidic regarding pH?
Animals tend to be on the basic side
Do plants tend to be basic or acidic regarding pH?
Plants tend to be on the acidic side
What is the pH of the water in Florida?
3
What are the 3 reasons cells need so much energy?
1. b/c they need to make energetically uphill reactions happen
2. to move molecules from low concentration to a high concentration
3. need energy to build things in a cell
What do small organisms rely mainly on to get their high energy molecules and carbon?
diffusion
What are some examples of high energy molecules?
proteins, sugars, fats, bananas, pigs, ets.
Definition of heterotrophy?
What we are, means we eat other living organisms that are either alive or dead to get our high energy molecules
Definition of autotrophy?
What plants are, means self-feeding aka photosynthesis to get their high energy molecules, use sunlight and gas from the air
Digestion
Process of breaking up the high energy molecules that we eat into smaller molecules so they can get into the cells through the plasmalemma
What is the process of digestion include?
Process starts in the mouth with the teeth that break the food into smaller molecules. Food then goes down the esophagus and enter the stomach.
What is the role of the stomach in digestion process? (3)
1. to store food so you don't have to eat constantly
2. stomach walls are muscles, and these muscles squish the food and breaks the food down more with these muscles
3. Chemically breaks down food so the smaller molecules can get into the cell through the plasmalemma
What is hydrochloric acid?
lots of protons and acid
What do antacids do?
balance out the acid in the stomach
What are the folds in the walls of the small intestine called?
mucosae
What does mucosae do?
increase the surface area of inside the small intestine for easier absorption
Where is the highest concentration of molecules in the small intestine?
the middle of it
What is diffusion?
the movement of substances and molecules from a high concentration to low concentration, energetically downhill
How do plant cells capture energy?
through photosynthesis
What is the process of photosynthesis?
The energy comes from sunlight, and then travels down in little packets called photons that travel in waves.
What are photons?
Little packets of energy that all have different amounts of energy and different wavelengths
Why is it possible to debate that plants may actually be heterotrophic?
Because of parasidic plants and parts of the plant are heterotrophic, like the roots, that depend on soil for their high energy molecules
Where do heterotrophic organisms get their energy and carbon from?
the SAME source
Where do autotrophic organisms get their energy and carbon from?
They get their energy from sunlight and their carbon from carbon dioxide in the air
Where do all living things on earth get their energy from?
sunlight
What is infared light/radiation?
About half of the photons from the sun have a long wavelength and low energy and are called infared light/radiation
What is UV?
About 5% of the photons from the sun are very short wavelength and high energy, called UV
What is the visible?
The other half of photons from the sun have intermediate wavelength and have intermediate levels of energy, called the VISIBLE and are the ones you can see. Around 400-700 wavelength.
Why do we depend on the visible light to excite our eyeballs?
B/c infared light has energy too low and UV light has energy too high
What is a pigment?
A pigment is usually a large molecule that share the same general properties no matter where they are (in your eye, in a plant, etc.), and they all have one "loose" electron
What is the absorption of the photon process?
Each pigment has a "loose" electron that when struck by a photon (visible light), the loose electron will be knocked down away from the positively charged nucleus. This is not where the electron should be, and now the pigment has higher energy. This happens in your eyeball all the time.
What pigment gets excited?
chlorophyll
What wavelengths do the colors blue and red have?
Blue=400. 700=red.
If we give a sun leaf and a shade leaf both really high light, how much chlorophyll fluorescence would you expect in the 2 leaves?
the shade leaf would show more fluorescence because there's more fluorescence under stress and the shade leaf would be stressed out because it is not used to all the sunlight
What protects the organism from bacteria that you get from the food you eat?
the small intestine
What is most of the bacteria you eat killed by?
the stomach's pH of 2
What is atrazine? Where is it in the chloroplast? What does it cause?
the world's most widely used pesticide that is toxic to most plants. It sits in the thylakoid membrane and prevents the electron from P680 and PQ, which kills the plant. It is an electron transfer inhibitor. It also causes the leaves to stop photosynthesizing.
Where is atrazine mostly found?
central kansas
T/F: NADPH has very high energy
True
What does the unequal distribution of protons across the membrane cause?
very high energy
How much energy does the lumen and the stroma have?
Lumen has a positive charge and the stroma has negative energy.
Where do th Dark Reactions occur?
in the stroma, must be in the light, NEVER in the dark
Where do ADP, P, and NADPH go after ATP is made?
they are recycled and go back to the stroma to make more sugar and become energized
What is another name for the Dark Reactions?
the calvin cycle
What is the enzyme that takes CO2 out of the air for plant photosynthesis and that is also the most abundant protein in the world?
Rubisco
What is released from the lumen?
oxygen
What is cellular respiration?
The process by which the energy in sugar is changed to energy in ATP
What is the role of the liver in digestion of food?
breaking up fat into small particles which can be absorbed
Where are the majority of digestive enzymes added to the food particles?
duodenum of the small intestine
What is the primary role of bile in digestion?
breaks apart large lipids into small lipids
Why is the production of bicarbonate by the pancreas important in digestion?
the digestive enzymes in the duodenum require a basic pH
Why is infared "light" ineffective in photosynthesis?
its energy level is too low to excite chlorophyll
If the pigments in your eye had an identical absorption spectrum as is characteristic of chlorophyll, which color would be difficult for you to see?
a green shirt
If a chlorophyll molecule were excited by a photon of blue light, what is the most likely nature of the photon released by the chlorophyll during fluorescence?
red
Approximately what proportion of the sun's photons striking the earth's surface can potentially be converted to sugar in a healthy plant?
1/2
What is a thylakoid?
a membrane inside of the chloroplast
What is meant by pigment excitation by light?
an electron goes to a higher energy level
If the chlorophyll molecule P700 in a leaf is struck by a photon with a wavelength of 400, what is the consequence?
it is excited, then it donates an electron to NADP
How does the pH of a chloroplast's lumen compare to that of its stroma for a healthy plant at noon in the sun?
higher in the stroma
Why is it impossible for the dark reactions to occur in the dark for a plant in nature?
there is no NADPH in the dark