BIOL1010- How Cells Obtain Energy (week 12)

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rRNA (ribosomal RNA)

molecules of RNA that combine to form part of the ribosome

Cellulose

one of the most abundant natural biopolymers; made up of glucose monomers that are linked by bonds between particular carbon atoms in the glucose molecule; a polysaccharide that makes up the cell walls of plants and provides structural support to the cell

Bulk transport (passive or active)

(active) In addition to moving small ions and molecules through the membrane, cells also need to remove and take in larger molecules and particles

Osmosis (passive or active)

(passive) (water is moving) transport of water through a semipermeable membrane according to the concentration gradient of water across the membrane that results from the presence of solute that cannot pass through the membrane

Diffusion (passive or active)

(passive) passive process of transport of low-molecular weight material according to its concentration gradient

Facilitated diffusion (passive or active)

(passive) process by which material moves down a concentration gradient (from high to low concentration) using membrane proteins

B. At the end of the Citric Acid Cycle

At what stage of respiration has the glucose been completely broken down and all CO2 released? A. At the end of glycolysis B. At the end of the Citric Acid Cycle C. After chemiosmosis D. After fermentation

-Photosynthesis is where plants use energy to convert carbon dioxide gas into sugar molecules (like glucose). They consume carbon dioxide and produce oxygen as a waste product. Formula: 6CO2 + 12H2O + Energy--->C6H12O6 + 6O2 + 6H2O -Cellular Respiration is a process that converts the energy stored in sugar molecules to ATP (the breakdown of sugar molecules to energy). The formula for the reaction is the reverse of photosynthesis. Formula: C6H12O6 + 6O2 + 6H2O--->6CO2 + 12H2O + Energy

Compare the purpose and formula of cellular respiration to photosynthesis.

-Endosymbiosis: a relationship in which one organism lives inside the other -Forms of evidence: 1. Grow and reproduce independently: Mitochondria & Chloroplasts can only arise from pre-existing mitochondria & chloroplasts; divide in two like bacteria 2. Synthesize their own proteins (1950's discovery) with similarities to bacteria in how proteins are made, reactions to antibiotics, etc. 3. Each have their own genome that resembles bacterial genome (e.g. circular chromosomes) - 1960's discovery 4. They have their own ribosomes (smaller and simpler than the ones in the rest of the cell, more similar to bacterial ribosomes) - 1980's 5. Infoldings of membranes on prokaryotes and mitochondria have similar functions (aerobic respiration) or photosynthesis (in chloroplasts and photosynthetic bacteria)

Define endosymbiosis and describe three forms of evidence that support the evolution of mitochondria and chloroplasts from bacteria.

-Anaerobic metabolic pathways occur in the absence of oxygen muscles -Examples: Lactic acid fermentation, alcohol fermentation -The fermentation method used by animals and some bacteria like those in yogurt is lactic acid fermentation. This occurs routinely in mammalian red blood cells and in skeletal muscle that has insufficient oxygen supply to allow aerobic respiration to continue. In muscles, lactic acid produced by fermentation must be removed by the blood circulation and brought to the liver for further metabolism. -Glycolysis: 2ATP -Oxidation phosphorylation: 36ATP -Fermentation: 2ATP

Describe anaerobic metabolic pathways, naming examples and describing their importance to humans. Compare ATP production between glycolysis, oxidative phosphorylation (aerobic cellular respiration) and fermentation

Mitochondrial DNA is prone to somatic mutations, which are a type of noninherited mutation. Somatic mutations occur in the DNA of certain cells during a person's lifetime and typically are not passed to future generations. There is limited evidence linking somatic mutations in mitochondrial DNA with certain cancers, including breast, colon, stomach, liver, and kidney tumors. These mutations might also be associated with cancer of blood-forming tissue (leukemia) and cancer of immune system cells (lymphoma). It is possible that somatic mutations in mitochondrial DNA increase the production of reactive oxygen species. These molecules damage mitochondrial DNA, causing a buildup of additional somatic mutations. Researchers are investigating how these mutations could be related to uncontrolled cell division and the growth of cancerous tumors.

Describe how a specific health condition (choose one) is related to a genetic mutation of mtDNA.

The Water (Hydrologic) Cycle: evaporation (water to water vapor)/ sublimation (ice to water vapor) -> condensation/ precipitation-> subsurface water flow (water flows beneath the surface) -> surface runoff/ snowmelt-> streamflow. Long term cycles: most of water/ stored in oceans, underground, ice. Short term cycles: surface water/ runoff water is how minerals are cycled from land to water. -it cools down an environment -helps climate and weather (is essential for both) The Carbon Cycle - rapid carbon exchange among living organisms: - the long-term cycling of carbon through geological processes: carbon is stored for long periods of time in reservoirs (the atmosphere, bodies of water, ocean sediment, soil, land sediments, Earth's interior)/ this is essential for the process of photosynthesis

Describe how matter cycles through an ecosystem using the hydrologic and carbon cycles as examples. Discuss long term (reservoirs) and short term cycles for each and the impact of each on climate.

-destruction of habitat (habitat loss) -introduction of exotic species -over-harvesting

Describe the activities that are having the greatest impact on extinction and biodiversity today.

-The building block is glucose (a simple sugar). -Role: provide energy to the body and have other important functions in humans, animals, and plants

Describe the composition (building block) and role of carbohydrates in living organisms.

A. NADH

During aerobic respiration what is the final electron acceptor in the electron transport chain? A. NADH B. carbon dioxide C. oxygen D. pyruvate E. all of these

the order of coordinated structures within the organism, how an organism responds to the environment, how an organism grows and reproduces depending on their genes, how an organism passes down their genetic information to their offspring, how the organism maintains their body temperature in various weather, how organisms process energy for their needs, and how genes change overtime in a population to create new species that are related to the original species -what is supported by metabolism: how organisms process energy for their needs

Describe the defining characteristics of living organisms [know which is supported by metabolism]

-Plasma membrane: has many functions, but the most basic one is to define the borders of the cell and keep the cell functional -Various roles: the surface of the plasma membrane carries markers that allows cells to recognize one another; separates the cell's interior from its surrounding environment, regulating the passage of substances into and out of the cell; formulates a boundary around the cell; regulates exchange; protects the immune system by not allowing things like pathogens enter; selectively permeable (it selects what comes in and out)

Describe the plasma membrane and its various roles in the cell.

-energy is stored in chemical bonds. it requires energy to form bonds and energy is released when bonds are broken -I believe that carbohydrates have more energy stored because it involves more chemical bonds than carbon dioxide.

Describe the relationship between energy and chemical bonds. Predict whether more energy is stored in carbon dioxide or carbohydrates.

-Hydrogen ions then diffuse through the inner membrane through an integral membrane protein called ATP synthase. -The flow of hydrogen ions across the membrane through ATP synthase is called chemiosmosis. -The electron transport chain and the production of ATP through chemiosmosis are collectively called oxidation phosphorylation. -The electron transport chain is present in multiple copies in the inner mitochondrial membrane of eukaryotes and in the plasma membrane of prokaryotes. -protons move against the gradient in chemiosmosis (active transport) -higher energy at the end of both electrochemical gradient in chemiosmosis -there is no gradient -oxygen bonds with the H+ electron at the end

Describe the relationship between the electron transport chain and chemiosmosis, explaining the importance of the mitochondrial membranes, the electrochemical gradient and the role of oxygen.

-Enzymes (are proteins), which are produced by living cells, are catalysts in biochemical reactions (like digestion). Each enzyme is specific for the substrate (a reaction that binds to an enzyme) upon which it acts. Enzymes can function to break molecular bonds, to rearrange bonds, or to form new bonds. They decrease the activation energy needed for a reaction to take place. -Changes in temperature, pH(acidity), and exposure to chemicals lead to permanent changes in the shape of the protein, leading to a loss of function or denaturation

Describe the role of an enzyme in a cell and explain how denaturation would affect its activity.

-Role of proteins: some of the proteins involved in facilitated diffusion form a pore or channel through the phospholipid bilayer; others are carrier proteins which bind with the substance and aid its diffusion through the membrane; channel proteins are specific for the substance that is being transported (recognize as self, signaling, transport, connects to the extracellular matrix)

Describe the role of proteins in facilitated diffusion [know ATP synthase]

A photon (aka packet of light energy) travels until it reaches a molecule of chlorophyll a. The photon causes the electron in the chlorophyll to become excited. The energy given to the electron allows it to break free from an atom of the chlorophyll molecule. In the light-dependent reactions, energy absorbed by sunlight is stored by two types of energy-carrier molecules: ATP and NADPH. In a series of reactions, the stored energy in ATP and NADPH is used to generate 3-carbon sugars that ultimately become a glucose (C6H12O6) molecule. Because the carbohydrate molecule has six carbon atoms, it takes six turns of the Calvin cycle to make one carbohydrate molecule (one for each carbon dioxide molecule fixed). The bonds in ATP and NADPH are broken to release energy, re-forming ADP, a phosphate group, and NADP+. This recycling makes them available again for the light dependent reactions.

Describe the transformation of energy in photosynthesis from photons to glucose, including the energy carriers that connect light dependent and independent reactions.

(eukaryotic) they enable plants to utilize the energy in sunlight to make sugars from carbon dioxide

Determine the role of chloroplasts

(eukaryotic) they harvest energy to power the cell...they supply the energy Determine the role of mitochondria

Determine the role of mitochondria

(eukaryotic) they contain the genetic information (DNA) for a cell and are involved in making ribosomes. The control center.... stores info needed for the cell to do anything that it needs to do.

Determine the role of nuclei.

(prokaryotic and eukaryotic) they are essential for protein production. They receive and transmit critical information

Determine the role of ribosomes.

-Passive transport: a naturally occurring phenomenon and does not require the cell to exert any of its energy to accomplish the movement; substances move from an area of higher concentration to an area of lower concentration -Active transport: mechanisms require the use of the cell's energy, usually in the form of adenosine triphosphate (ATP); substances move from an area of lower concentration to an area of higher concentration

Distinguish between passive and active transport.

-Monosaccharides are simple sugars, the most common of which is glucose; they may exist as a linear chain or as ring-shaped molecules; in aqueous solutions, they are usually found in ring form. -Polysaccharides is a long chain of monosaccharides linked by covalent bonds; may be very large molecules (ex. starch, glycogen, cellulose, chitin)

Distinguish monosaccharides from polysaccharides

Anaerobic process

Does glycolysis go through an anaerobic or aerobic process?

Gene expression in cells controls whether a gene is expressed or not; say only this amount of proteins are going to be made this way. This affects protein levels by: transcription stops when protein is not needed (more transcription= more proteins)

Evaluate the importance of gene expression in cells, describing how it affects protein levels.

When heat energy from the sun strikes the Earth, gases known as greenhouse gases trap the heat in the atmosphere. Greenhouse gases reflect much of the thermal energy back to Earth's surface. The more greenhouse gases there are in the atmosphere, the more thermal energy is reflected back to Earth's surface.

Explain how greenhouse gases influence the Earth's climate

-Glycolysis is a primitive metabolic pathway because most cells and types of cells are using it (prokaryotes/ eukaryotes) -the products are: ATP, NADH, pyruvate (2)

Explain how it is known that glycolysis is a primitive metabolic pathway and name the products

chemical reactions do not take place on their own. Each reaction step is facilitated, or catalyzed, by a protein called an enzyme. Enzymes are important for catalyzing all types of biological reactions-those that require energy as well as those that release energy.

Explain how metabolic pathways harvest energy efficiently.

The First Law of Thermodynamics states that energy can neither be created or destroyed (each level must acquire energy from the trophic level below). The Second Law of Thermodynamics states that, during the transfer of energy, some energy is lost as heat (less energy is available at each higher trophic level). Energy pyramids must always be upright because of these two laws.

Explain how the first and second laws of thermodynamics are related to the flow of energy through a food web.

The advantage of using mtDNA to trace ancestry compared to the DNA found in the nucleus is because mtDNA only comes from the mother, it does not change very much, if at all, from generation to generation. Mutations do occur, but not very often- -less frequently than once per 100 people. Therefore, a person's mtDNA is probably identical to that of his or her direct maternal ancestor a dozen generations ago, and this fact can be used to connect people across decades. The challenges are: Therefore, a local area where she lived will be the only place in the world where this particular type of mtDNA is found. However, whenever people moved from one place to another they took their mtDNA with them. A second problem is that many African-Americans have a particular type of mtDNA that is clearly African in origin, but has not yet been observed among the African mtDNAs that have been analyzed. However, if a particular mtDNA is rare enough to be found in only a small region of Africa, there is a good chance it will be difficult for researchers to find it

Explain the advantage of using mtDNA to trace ancestry, compared to the DNA found in the nucleus. Explain the challenges.

-Enzymes are key components of metabolic pathways; most enzymes are proteins and perform the critical task of lowering the activation energies of chemical reactions inside the cell -The selective production of enzymes and other proteins needed by a particular cell is driven by which particular genes are copied and translated (gene expression). -Vitamin C is a direct enzyme for multiple enzymes that take part in building the important connective tissue, collagen. Therefore, enzyme function is, in part, regulated by the abundance of various cofactors and coenzymes, which may be supplied by an organism's diet or, in some cases, produced by the organism

Explain the importance of enzymes in metabolism and how our diet supports enzyme function by supplying co-factors and co-enzymes.

Teeth are considered to be conserved because throughout evolution, gene mutations that are associated with tooth abnormalities have evolved. Not all elephants are growing tusks, therefore there are a small amount of elephants that have tusks and we need to conserve them and protect them -Glycolysis: the process of breaking glucose into three-carbon molecules with the production of ATP and NADH -Cytochrome C: an important component of the molecular machinery that harvest energy from glucose. Because this protein's role in producing cellular energy is crucial, it has changed very little over millions of years

Explain what "conserved" means in evolutionary terms [discuss each of these: cytochrome c, glycolysis]

Fossil fuels are considered a non-renewable resource because their use far exceeds their rate of formation. A non-renewable resource, such as fossil fuels, is either regenerated very slowly or not at all ***[compare products of fermentation and respiration to the burning of fossil fuels]***

Explain why carbon stored in fossil fuels is a non-renewable resource [compare products of fermentation and respiration to the burning of fossil fuels].

C. all mitochondria come from the mother

How is mitochondrial DNA inherited? A. half comes from eggs and half from sperm B. all mitochondria come from the father C. all mitochondria come from the mother D. they come from the microbiome

-At the end of the citric acid cycle -CO2 (carbon dioxide)

Know at what stage the glucose molecule has been completely broken down and the waste product that is formed.

Mitochondrial DNA contains 37 genes, all of which are essential for normal mitochondrial function. Thirteen of these genes provide instructions for making enzymes involved in oxidative phosphorylation. Oxidative phosphorylation is a process that uses oxygen and simple sugars to create adenosine triphosphate (ATP), the cell's main energy source. The remaining genes provide instructions for making molecules called transfer RNA (tRNA) and ribosomal RNA (rRNA), which are chemical cousins of DNA. These types of RNA help assemble protein building blocks (amino acids) into functioning proteins.

Know what types of proteins are encoded in mtDNA, also called the mitochondrial genome. Explain why genes for ribosomal RNA would be needed in the mitochondria.

B. NADH

NAD+ enters the Citric Acid Cycle and leaves as NADH. Which is storing more potential energy? A. NAD+ B. NADH C. They are the same

-ATP (adenosine triphosphate) -mitochondria are responsible for making ATP. The formation of ATP from the breakdown of glucose is know of cellular respiration

Name the cell's main energy-carrier and how it is produced.

-The four classes are: carbohydrates, lipids, proteins, and nucleic acids. -They all contain carbon, hydrogen, and oxygen. -an enzyme is a protein

Name the four classes of biological macromolecules and state what elements they all have in common [know which type is an enzyme]

A. ATP

The energy currency used by cells is ________ A. ATP B. ADP C. AMP D. adenosine

D. Pyruvate

The glucose that enters the glycolysis pathway is split into two molecules of A. ATP B. Phosphate C. NADH D. Pyruvate

There are two types of metabolic pathways: catabolic and anabolic. -Anabolic reactions: small molecules are built into large ones. Energy is required. Anabolic reactions are endergonic. Endergonic reaction: (energy is absorbed) this reaction will not take place without the addition of energy; their products have more energy than the reactants; the chemical reaction absorbs more energy than it releases, the products of these reactions are energy-storing molecules

What are anabolic reactions, discuss the difference between reactants and products and whether energy is harvested or stored in each reaction. Identify if it is endergonic or exergonic.

There are two types of metabolic pathways: catabolic and anabolic. -Catabolic reactions: large molecules are broken down into small one. Energy is released. Catabolic reactions are exergonic. Exergonic reaction: (energy is exiting the system) their products have less stored energy than the reactants; since the chemical reaction releases more energy than it absorbs, the products of these reactions are energy-harvested molecules

What are catabolic reactions, discuss the difference between reactants and products and whether energy is harvested or stored in each reaction. Identify if it is endergonic or exergonic.

Archaea and bacteria

What are the two domains that are prokaryotes?

A. The electrochemical gradient of protons (H+)

What best describes the potential energy that is generated by the electron transport chain? A. The electrochemical gradient of protons (H+) B. The oxygen that we breathe C. The food we eat D. The ATP synthase enzyme

D. all of these

What do all mitochondria have? A. membranes B. ribosomes C. DNA D. all of these

A. easier to trace with less variation through generations

What is an advantage of using mtDNA to trace ancestry, compared to the DNA found in the nucleus A. easier to trace with less variation through generations B. high mutation rate makes it easy to determine relatives C. very large genome, relative to the chromosomes D. passed from father to son with the Y chromosome

C. there are areas where no DNA has been collected

What is one challenge of using mitochondrial DNA to determine ancestry? A. there has not been enough movement of human populations B. there are no unique alleles, all are common C. there are areas where no DNA has been collected D. it is not always inherited

C. Metabolism

What is the collective term for all of the biochemical processes occurring within a cell? A. Catabolism B. Anabolism C. Metabolism D. Syntheses

Eukarya

What is the domain that is a eukaryote?

D. Cellular Respiration

What is the metabolic pathway that harvests energy from food? A. Photosynthesis B. ATP synthase C. Biosynthesis D. Cellular Respiration

human activity release the two most important gases (carbon dioxide and methane). Such activities for carbon dioxide include: burning fossil fuels, deforestation, animal agriculture. Methane is produced when bacteria break down organic matter under anaerobic conditions. ***describe the connections between photosynthesis and cellular respiration to greenhouse gases***

What is the reason for greenhouse gas increase over the past century.

The fact that energy can be released by the breakdown of certain chemicals bonds implies that those bonds have potential energy.

What type of energy (kinetic or potential) identify with chemical bonds?

B. At the end of the citric acid cycle

When is the glucose completely broken down and all carbon dioxide released? A. At the end of glycolysis B. At the end of the citric acid cycle C. After chemiosmosis D. After fermentation

D. Glycolysis

Which is the most primitive and widespread metabolic pathway for breaking down sugars for living organisms? A. Krebs Cycle B. Aerobic respiration C. Photosynthesis D. Glycolysis E. All of these

A. Aerobic cellular respiration

Which metabolic pathway produces the highest number of ATP molecules? A. Aerobic cellular respiration B. Fermentation C. Glycolysis D. All of these are equal

D. Photosynthesis transfers solar energy to chemical energy; respiration breaks down chemical bonds to extract energy.

Which of the following accurately describes the relationship between photosynthesis and cellular respiration? A. Photosynthesis only occurs in autotrophs and cellular respiration only occurs in heterotrophs. B. Photosynthesis transfers energy from carbon dioxide into glucose; respiration transfers energy from oxygen into glucose. C. Photosynthesis and cellular respiration cannot occur at the same time. D. Photosynthesis transfers solar energy to chemical energy; respiration breaks down chemical bonds to extract energy.

A. A proton gradient that will be used to run ATP synthase.

Which of the following describes the potential energy that is made available through the Electron Transport chain? A. A proton gradient that will be used to run ATP synthase. B. An oxygen molecule that accepts electrons leaving the ATP synthase. C. Water molecules that form after oxygen accepts an electron. D. ADP that will be phosphorylated to ATP.

A. lactic acid fermentation

Which of the following fermentation methods can occur in animal skeletal muscles? A. lactic acid fermentation B. alcohol fermentation C. mixed acid fermentation D. propionic fermentation

C. C6H12O6+ 6O2 + 6H2O--->6CO2 + 12H2O + Energy

Which of the following is the correct formula for cellular respiration? A. C6H12O6 + 6O2 --->12H2O+ 6CO2 + Energy B. C6H12O6+ 6CO2 + 6H2O--->6O2 + 12H2O + Energy C. C6H12O6+ 6O2 + 6H2O--->6CO2 + 12H2O + Energy D. 6CO2 + 12H2O --->C6H12O6+ 6O2 + 6H2O

B. potential

Which of these best describes the energy stored in the bonds of a glucose molecule? A. activation B. potential C. kinetic D. all of these

A. genes that code for enzymes involved in oxidative phosphorylation

Which of these describe genes found in mitochondrial DNA? A. genes that code for enzymes involved in oxidative phosphorylation B. genes for chromosomal replication C. genes that are involved in mitosis D. genes for proteins involved in glycolysis

B. They are exergonic, releasing energy as they break down complex chemicals.

Which of these is true of catabolic reactions? A. They are endergonic, harvesting energy as they break down complex chemicals. B. They are exergonic, releasing energy as they break down complex chemicals. C. They are exergonic, storing energy as they synthesize complex chemicals. D. They do not rely on enzymes.

C. They are organic helper molecules and sometimes vitamins

Which of these is true of co-enzymes? A. They interfere with enzyme functions through competition B. They are inorganic ions C. They are organic helper molecules and sometimes vitamins D. They have no role in metabolism

Bacteria and Archaea (prokaryotes). Can they survive and reproduce?

Which organisms are most successful? What is the main question that is asked?

A. Aerobic cellular respiration

Which type of metabolic pathway produces the highest number of ATP molecules? A. Aerobic cellular respiration B. Fermentation C. Glycolysis D. All of these are equal

B. Enzymes that facilitate the chemical reactions are in the membranes.

Why are mitochondria important in aerobic cellular respiration? A. They prevent proton gradients from forming. B. Enzymes that facilitate the chemical reactions are in the membranes. C. They keep oxygen out of the system. D. They lack membranes.

A. the same genetic mutations for missing teeth are found in mice and people

Why are teeth considered to be "conserved?" A. the same genetic mutations for missing teeth are found in mice and people B. teeth grow the same way in every animal with no evolution C. there are no teeth in the fossil record because they break down quickly

F. all of these

Why do cells need a source of energy? A. break down complex food molecules B. fight off pathogens C. active transport of molecules D. synthesis of molecules the cell needs E. movement of the cell F. all of these

6CO2+12H2O+Energy--light enzymes-->C6H12O6+6O2+6H2O

Write the balanced formula for photosynthesis from your text.

Draw a Hydrogen atom, labeling the location of protons, neutrons and electrons.

a Hydrogen atom includes 1 proton and 1 electron. There may be 0, 1, 2 (these are different isotopes of Hydrogen)

ATP synthase

a membrane-embedded protein complex that regenerates from ADP with energy from protons diffusing through it

tRNA (transfer RNA)

a type of RNA molecule that brings amino acids to the growing chain of the polypeptide; the molecules that "translate" the language of the RNA into the language of proteins; for each of these to function, it must have a specific amino acid bonded to it

Metabolism

all the chemical reactions that take place inside cells, including those that use energy and those that release energy (composed of synthesis (anabolism) and degradation (catabolism)

Glucose

an important source of energy

mRNA (messenger RNA)

carries the code ("message") to form a protein process called translation; a form of RNA that carries the nucleotide sequence code for a protein sequence that is translated into a polypeptide sequence

Kinetic energy

energy associated with objects in motion

Potential energy

energy associated with position and the force of gravity acting on it; the type of energy that refers to the potential to do work

Energy

the ability to do work, or to create some kind of change

Electrochemical gradient.

the combined gradient of concentration and electrical charge that affects an ion; gradient produced by the combined forces of an electrical gradient and a chemical gradient

net primary productivity (NPP)

the energy that remains in the primary producers after accounting for the organisms' respiration and heat loss

Genome

the entire genetic complement (DNA) of an organism

biogeochemical cycle

the recycling of inorganic matter between living organisms and their environment; cycling of mineral nutrients through ecosystems and through the non-living world

Glycogen

the stored form of glucose in humans ans other vertebrates, and is made up of monomers of glucose; a storage carbohydrate in animals

Starch

the stored form of sugars in plants and is made up of amylose and amylopectin (both polymers of glucose); a storage carbohydrate in plants


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