Biology 1610 exam 2

non-competitive inhibitor

A compound that binds to an allosteric site, other than the active site, to decrease the activity of an enzyme

steroids

A lipid that has a backbone of 3 six-Carbon rings (hexagons) hooked to a five-Carbon ring. They are used in cell membrane structure and also in signaling

phosphorylation

Adding a Phosphate group to a molecule turgor pressure

Direct, Endocrine, Paracrine

How a Signal Travels to the Target

simple diffusion

O2 In this cell type there is a high gradient of O2 outside of the cell and a low gradient inside of the cell. This cell needs to move more O2 from outside of the cell to the inside of the cell.

There are several ways in which a signaling ligand will leave the source cell and travel to the target cell. Signal ligands, such as [ Select ] ["amino acids", "proteins", "eicosanoids"] , can pass through the source cell membrane without the help of a transport protein and are usually [ Select ] ["small", "large"] and/or [ Select ] ["hydrophobic", "hydrophilic"] . These types of ligands leave the source cell using [ Select ] ["exocytosis", "simple diffusion", "primary active transport", "facilitated diffusion"] and are made [ Select ] ["as needed because they can't be stored for later", "any time and stored for later use in a vesicle"] . Signal ligands, such as [ Select ] ["eicosanoids", "steroids", "amines"] , can NOT pass through the source cell membrane without the help of a transport protein and are usually [ Select ] ["small", "large"] and/or [ Select ] ["hydrophobic", "hydrophilic"] . These types of ligands leave the source cell using [ Select ] ["exocytosis", "osmosis", "simple diffusion"] and are made [ Select ] ["as needed because they can't be stored for later", "any time and stored for later use in a vesicle"] . When traveling to the target cells, ligands can use different routes. *Gap junctions in animals and [ Select ] ["tight junctions", "desmosomes", "plasmodesmata"] in plants are tiny channels that connect neighboring cells and allow for [ Select ] ["paracrine", "direct", "endocrine"] communication. *The type of signaling in which cells communicate over relatively short distances is known as [ Select ] ["direct", "paracrine", "endocrine"] signaling. One unique example of this type of signaling is [ Select ] ["hormonal", "synaptic", "juxtacrine"] signaling, in which the source cell is a neuron. In [ Select ] ["endocrine", "juxtacrine", "autocrine"] signaling, a cell signals to itself, releasing a ligand that binds to its own cell surface or intracellular receptors. * In [ Select ] ["endocrine", "direct", "paracrine"] signaling, ligands (known as hormones) travel to target cells through the blood.

eicosanoids, small, hydrophobic, simple diffusion, as needed because they can't be stored for later, amines, large, hydrophilic, exocytosis, any time and stored for later use in a vesicle, plasmodesmata, direct, paracrine, synaptic, autocrine, endocrine

kinetic energy

energy of movement

Which of the following statements are TRUE? Choose all that Apply

enzymes can couple an endergonic reaction to an exergonic reaction, Enzymes speed up reactions by decreasing the activation energy required to start the reaction

Look at the diagram of a chemical reaction shown below. Then identify each of the following : The reactants in this reaction are [ Select ] ["molecules A and B", "molecules C and D"] . The products of this reaction are [ Select ] ["Molecules A and B", "molecules C and D"] . The free energy change,( ΔG) of this reaction is [ Select ] ["d", "a", "c", "b"] . The activation energy needed for this reaction, without an enzyme present is [ Select ] ["b", "a", "c", "d"] . The activation energy needed for this reaction, with an enzyme present is [ Select ] ["c", "d", "b"] .

molecules A and B, molecules C and D, d, c, b

Some proteins can renature (re-fold) after having been denatured.

true

anabolic reaction

type of reaction that is not spontaneous, is endergonic and has a + ΔG

enzyme

A chemical agent that selectively increases the rate of a reaction without being consumed by the reaction

second messenger

A small, nonprotein intracellular signaling molecule such as DAG or IP3

pinocytosis

A type of endocytosis in which the cell ingests extracellular fluid and its dissolved small solutes

triglyceride

A very large lipid that is used for long-term energy storage. They have a location that is hydrophlic (made from part of a sugar) and three long locations of hydrophobic hydrocarbons

Response

Change in Vm (electrochemical gradient), Change in Metabolic Rate, Change in Gene Expression

isotonic

Concentration of material is equal on either side of the cell membrane. The solution the cell is in is considered this.

hypotonic

Concentration of material is greater inside the cell than outside the cell. The solution that the cell is in is considered this

hypertonic

Concentration of material is greater outside the cell than inside the cell. The solution the cell is in is considered this.

secondary active transport

Cysteine (an amino acid). In this cell type there is a high concentration of cysteine inside of the cell and a low concentration of cysteine outside of the cell. This cell needs to move more Cysteine inside of the cell

denaturation

Destruction of both the secondary and tertiary structures of proteins

1st law of thermodynamics

Energy cannot be created or destroyed, but can change form is known as ____.

2nd law of thermodynamics

Entropy must always increase

Which of the following could use bulk transport? Choose all that apply.

Epinephrine (a catecholamine), Glutamate (an amino acid), ADH (a peptide), Serotonin (an amine), Prolactin (a peptide)

Which of the following molecules cannot pass through the cell membrane on its own (without the help of proteins and/or membrane-bound vesicles)? Choose all that apply?

Glucose, Lysine (an essential amino acid), DNA, Triglyceride

facilitated diffusion

Mg2+ in a cell where there is a high gradient outside of the cell and a low gradient of this ion inside of the cell. The cell needs to move more Mg2+ inside of the cell.

primary active transport

Na+ in a cell with a high gradient of Na+ outside and a low gradient of Na+ on the inside. This cell needs more Na+ to go outside of the cell

Termination

One way to do this is to degrade the signaling molecule after it detaches from its receptor

exocytosis

Peptides (small proteins). A cell has a lot of these small proteins inside of the cell and not as many of these proteins outside of the cell. This cell needs to move a lot of these peptides out of the cell all at once

enthalpy

Potential energy of system

endocrine- hormone

Signal travels to the target cell through the blood

Juxtacrine - Direct Contact

Source and/or target moves to communicate

Plasmodesmata - Direct Contact

Source cell interacts directly with the target cell and shares Smooth ER

Synaptic - Paracrine

Source cell is a neuron and is separated from the target by a short distance

Autocrine - Paracrine

Source cell is the target cell

Gasses, Amino Acids, Amines, Eicosanoids, Steroids and Proteins/Peptides

The Source Produces the Signaling Molecule

Intracellular, G-protein linked, Enzyme linked or Ion channel linked

The Target Cell is the cell that has the receptor for that particular signling molecule

allosteric inhibitor

The binding of an inhibitor at a site other than the active site; noncompetitive inhibition

Which of the following statements is NOT TRUE about the reaction below? A → C + D + energy

The cell must use ATP for this reaction to occur

turgor pressure

The force directed against a plant cell wall after it has swelled due to osmosis

phosphorylation

The process of adding a phosphate group to another molecule

phospholipid

These are amphipathic molecule that make up the majority of chemicals in the cell membranes of eukaryotes

gap junctions

These channel-like structures are found in animal cells, made of connexin proteins and allow signaling between the two cells.

plasmodesmata

These junctions are found in eukaryotic cells with cell walls and allow for communication through the smooth ER between the cells

desmosomes

These junctions use flexible cadherin proteins to hold cells together

tight junctions

These junctions use occludin/claudin proteins to bind together two cell membranes.

carotenoids

These long lipids also have ring structures that reflect orange or yellow light so appear those colors

eicosanoids

This class of lipid are used in cell signaling (such as blood clotting and immune function)

primary structure

This level of structure is caused by four types of interactions: Disulfide bonds, Ionic bonds, Hydrogen Bonds and Hydrophobic interactions between the R-groups on the amino acids

secondary structure

This level of structure is caused by hydrogen bonding between backbone elements of amino acids

quaternary structure

This level of structure is dictated by the Interactions between two or more proteins

Choose all of the following that are true about the molecule pictured above.

This molecule contains a carboxyl group, All of the Carbon to Carbon double bonds are in the cis configuration, This molecule is an unsaturated fatty acid, This molecule contains a methyl functional group, This molecule is a fatty acid

Which of the following are true about the macromolecule that is pictured above? Choose all that apply

This molecule contains a phosphate functional group, An unsaturated fatty acid is part of this molecule, It is amphipathic, It is a phospholipid, A saturated fatty acid is part of this molecule

In Chapters 7-11, we discussed many concepts related to proteins, lipids, membranes, transport, and cell signaling. Select all that are true statements.

Tight junctions use occludins to seal off body cavities so they can't leak into each other, Lysosomes are part of the endomembrane system, Water flows from a hypotonic solution to a hypertonic solution, Translation (the process of building a protein using RNA as instructions) is an anabolic process, Active transport is an endergonic process, Phosphorylation of ADP in aerobic respiration is an endergonic process, Ca2+ is an example of a second messenger

Ca2+, IP3, cAMP, DAG, cGMP

Transduction

transport work

Type of work done by using ATP to drive the movement of solutes from an area of lower concentration to an area of higher concentration

coupled reaction

Using energy released from an exergonic reaction to power an energonic reaction .

Insulin is a protein hormone in humans and other animals. Choose all of the following that would be true of this signaling molecule

When it reaches its target cell it binds with a cell surface receptor, It travels through the blood from the source cell to the target cell, It is released from its source cell through exocytosis, It is made in the rough ER and moves to the Golgi apparatus and then through vessicle movement to the cell surface membrane

A drug that decreases the activity of an enzyme, by binding to its active site, is called _____?

a competitive inhibitor

A is pointing to [ Select ] ["a large phospholipid", "the steroid cholesterol", "a peripheral/integral membrane protein", "an iECF surface protein"] B is pointing to [ Select ] ["an ICF peripheral membrane protein", "cholesterol", "an integral/transmembrane protein", "a specific type of phopholipid"] C is pointing to [ Select ] ["the steroid cholesterol", "a transmembrane protein", "a strangely shaped phospholipid", "a peripheral membrane protein", "an integral membrane protein"] D is pointing to [ Select ] ["a very large phospholipid", "an eicosanoid", "a transmembrane protein that is a channel transporter", "a transmembrane protein that is a carrier protein"] E is pointing to [ Select ] ["a phospholipid", "a transmembrane carrier", "cholesterol", "a transmembrane channel"] F is pointing to

a peripheral/integral membrane protein, an integral/transmembrane protein, the steroid cholesterol, a transmembrane protein that is a channel transporter, a phospholipid, the phospholipid bilayer

enzyme

a protein that functions to catalyze chemical reactions

When a cell is at chemical equilibrium it ______

can no longer do work and will die.

Which of the following is an example of potential energy, rather than kinetic energy?

chemical bonds in a molecule of glucose

Singer and Nicolsen described plasma membranes as a [ Select ] ["fluxional gallimaufry", "polymerization and adhesion", "fluid mosaic", "Hodgkin and Huxley"] model. The second part of the model name comes because of the different components that make up the plasma membrane. The part that makes up most of the plasma membrane are [ Select ] ["steroids", "phospholipids", "triglycerides", "eicosanoids"] and because of its [ Select ] ["dualized hydrophobic", "bivalent", "amphibious", "amphipathic"] properties it forms a [ Select ] ["monolayer", "alpha helix", "bilayer", "trilayer", "double helix"] . The structure of phospholipid bilayers are critical to membrane function. Because the interior of the phospholipid bilayer is occupied by the hydrophobic fatty acid chains, the membrane is impermeable to large hydrophilic biomolecules like [ Select ] ["O2 (gas)", "H2O", "carotenoids", "amylose (starch)"] or charged molecules like [ Select ] ["Ca2+", "eicosanoids", "steroids", "CO2"] . In addition to phospholipids, the membrane also contains [ Select ] ["alpha glucose", "thromboxanes", "DNA", "cholesterol"] which sits near the fatty acid tails and helps in membrane fluidity. Another membrane component that helps in cell recognition and in the [ Select ] ["semi-", "selectivity", "non-"] permeable property of cell membranes are membrane [ Select ] ["nucleic acids", "spaces", "carbohydrates", "proteins"] . If these components are on the outside of the membrane (and not embedded), they are known as [ Select ] ["peripheral", "collaborative", "integral", "transmembrane"] . If they are embedded in the membrane they are known as integral . If these embedded components go all the way through the membrane from one side to the other they are also known as [ Select ] ["peripheral proteins", "transmembrane proteins", "cismembrane proteins", "connecting proteins"] . Membrane proteins have numerous functions. Proteins that provide a pathway for large and/or hydrophilic molecules to move across the membrane are called [ Select ] ["conveyor", "transport", "discharge", "receptor"] proteins. [ Select ] ["carrier", "channel"] proteins do NOT change shape (but can have gates) and can move solutes using facilitated diffusion across the membrane down their concentration gradient but cannot move solutes against their concentration gradient. carrier proteins change shape and can perform both active transport and facilitated diffusion.

fluid mosaic, phospholipids, amphipathic, bilayer, hydrophobic, amylose (starch), Ca2+, cholesterol, selectivity, proteins, peripheral, integral, transmembrane proteins, transport, channel, carrier

There are carbohydrates and even simple sugars that are associated with the cell membrane. If a carbohydrate is bound to a phospholipid in the membrane it is called a _____ . If a carbohydrate is bound to a membrane-bound protein then that carbohydrate is called a _______ .

glycolipid, glycoprotein

osmosis

h2o

It is important that cells maintain [ Select ] ["homeostasis", "equilibrium"] . By this we mean they must maintain the correct pH, the correct amount of small and large molecules, the correct temperature, etc. To do this process requires work. The three types of cellular work are [ Select ] ["transport work, chemical work and mechanical work", "Active transport, passive transport and facilitated diffusion", "dehydration reactions, hydrolysis reactions and redox reactions", "motor proteins, vesicles and microtubules"] . For example, cells must transport ions, such as Na+ or H+ across cell membranes. To do work requires energy. Metabolism is all the chemical reactions taking place in your cell. [ Select ] ["Catabolism", "Anabolism", "Metabolism"] refers to reactions that build molecules and require energy whereas [ Select ] ["Metabolism", "Anabolism", "Catabolism"] is the reactions that break down molecules to release energy. Cells harvest energy by doing the metabolic process of [ Select ] ["energy", "big muscles", "photosynthesis", "glycolysis", "aerobic cellular respiration"] . In this process cells break down the covalent bonds in glucose, a higher energy molecule, to produce the lower energy molecules, carbon dioxide and water. In this exergonic process, energy is [ Select ] ["used", "released"] . Enzymes in the mitochondria are able to harvest some of the energy and use it to phosphorylate ADP to build [ Select ] ["glucose", "ATP", "sugar", "fat"] . This activated energy carrier molecule can then be used to power work taking place throughout the cell. The energy that is not harvested during this process becomes [ Select ] ["enthalpy", "Gibbs free energy", "entropy"] . This form of energy shows up mostly as heat. In contrast, Equilibrium is [ Select ] ["bad", "good"] for cells. When a cell is at equilibrium it can no longer do the work of staying alive. Organisms avoid reaching equilibrium by eating and by getting rid of waste every day. They can do this because cells are [ Select ] ["Closed", "Open"] systems. If your cells reach equilibrium they can no longer do the work of staying alive, and therefore, once you run out of ATP, you die. You need to eat each day so your cells will have complex molecules, such as glucose, which they can then break down by the process of cellular respiration. Most of the enzymes that catalyze aerobic cellular respiration to produce ATP are located in the [ Select ] ["nucleus", "lysosomes", "mitochondria", "smooth endoplasmic reticulum", "chloroplasts"]

homeostasis, transport work/chemical work and mechanical work, anabolism, catabolism, aerobic cellular respiration, released, ATP, entropy, bad, open, mitochondria

Which of the following terms are associated with cellular reactions in which larger, higher energy molecules are broken down into smaller, lower energy products? (Mark all that are correct)

hydrolysis reaction, spontaneous, exergonic, -delta G, releases energy, catabolic

If you have a high [testosterone] outside of the cell compared to a low [testosterone] inside the cell, how could you get testosterone to move from the inside of the cell to the outside of a cell? Hint: Testosterone is a steroid

it cannot be done

A hormone ligand leaves the source cell through exocytosis. Select ALL that could be true about this ligand molecule.

it travels to the target cell through the blood, it is potentially received by an enzyme-linked receptor, it could be an amino acid

Which of the following would use intracellular receptors in the target cell? (select all that apply)

nitric oxide (a gas), progesterone (a steroid), thromboxane A2 (an eicosanoid), retinol (a carotenoid)

The Na+/K+ pump moves 3 Na+ [ Select ] ["into the cell", "around the cell", "out of the cell"] and 2 K+ into the cell and uses 1 [ Select ] ["ATP", "DNA", "Photons (light)"] to do it!

out of the cell, into the cell, ATP

Which of the following processes require the cell to input energy? Select ALL that apply.

phagocytosis, secondary active transport, primary active transport, receptor-mediated endocytosis, pinocytosis, exocytosis

The picture above is a short protein. This protein is shown in its [ Select ] ["pentary", "secondary", "tertiary", "septary", "quarternary", "primary"] . There are [ Select ] ["1", "2", "3", "0", "4"] peptide bonds present in this protein. The first amino acid in this structure is a [ Select ] ["charged - acidic", "polar", "charged - basic", "non-polar"] amino acid. The second amino acid in this structure is a [ Select ] ["non-polar", "polar", "charged-basic", "charged - acidic"] amino acid. The third amino acid in this structure is a [ Select ] ["non-polar", "charged - acidic", "polar", "charged - basic"] amino acid.

primary, 2, charged-acidic, non-polar, polar

Cell transport is essential for life. If you are feeling stressed right now you are making the steroid hormone cortisol. Since the cell making cortisol has a high concentration of cortisol compared to outside the cell, that cell will use [ Select ] ["simple diffusion", "secondary active transport", "facilitated diffusion", "bulk transport", "primary active transport"] to move that cortisol from inside, where is was made in the [ Select ] ["rough ER", "mitochondria", "smooth ER", "nucleus", "lysosome"] , to outside of that cell. If you are really scared of this quiz (which, we hope you are not because you have studied and know you are prepared) then the cells of your adrenal medulla might be releasing large amounts of epinephrine - a, large, hydrophilic, catecholamine - into your blood all at the same time using [ Select ] ["pinocytosis", "simple diffusion", "secondary active transport", "phagocytosis", "primary active transport", "facilitated diffusion", "exocytosis"] . Both of these hormones - the cortisol and epinephrine - can help you deal with the stressful situation. Part of cell transport is the moving of ions. These ions are often called electrolytes. If a cell has a high gradient for Mg2+ outside of the cell (compared to the inside of the cell) then that cell would use [ Select ] ["simple diffusion", "facilitated diffusion", "secondary active transport", "primary active transport", "pinocytosis"] to move that Mg2+ from outside of the cell to the inside of the cell. If that same cell had a high gradient of K+ inside of that cell and a low gradient of K+ outside of the cell and the cell needed to get more K+ into it then that cell would use [ Select ] ["secondary active transport", "simple diffusion", "receptor-mediated endocytosis", "primary active transport", "facilitated diffusion"] to move that K+ inside. Cells can also move nutrients as part of transport. Glucose is a [ Select ] ["protein", "nucleotide", "amino acid", "carbohyrate", "nucleic acid", "simple sugar"] monomer, and, therefore, is very hydrophilic. If a cell had a high concentration of glucose inside of it but needed more glucose inside (such as when a cell is making glycogen) then it can use [ Select ] ["secondary active transport", "exocytosis", "pinocytosis", "simple diffusion", "primary active transport", "facilitated diffusion"] in order to transport more glucose inside. If another cell had a high concentration of the amino acid alanine outside of it (and a low concentration of alanine inside of it) that that cell could transport alanine inside of the cell using [ Select ] ["primary active transport", "secondary active transport", "facilitated diffusion", "simple diffusion", "phagocytosis", "exocytosis"] .

simple diffusion, smooth ER, exocytosis, facilitated diffusion, primary active transport, simple sugar, secondary active transport, facilitated diffusion

Cell Signaling is how cells talk to themselves and how they talk with other cells! Step 1 of cell signaling is the [ Select ] ["cardiac", "source", "lymphatic", "target"] cell produces the signaling molecule. The molecule that the signal binds with is the receptor which is step 2; this structure is located on or in the target cell. Step 3 is [ Select ] ["transduction", "transcription", "translation", "termination"] which is a multi-step, intracellular, mechanism that usually uses small, mobile chemicals called second messengers. These small, mobile, intracellular chemicals include cAMP, cGMP, IP3, DAG and Ca+2. The fourth step of cell signaling is Response. Cellular responses can fall into 1, 2 or all 3 of the following categories: Change in membrane potential (battery charge - open/close ion channels), [ Select ] ["Change the mechanism of mitosis (grow faster or slower)", "Change in gene expression (turn on/off a gene)", "Change the type of cell it is (change the membrane characteristics)", "Change the way the cell signals the other cells (make more or less second messengers)"] , and Change in metabolic rate (use more or less energy). And finally, the last step of the cell signaling cascade is Termination - this step usually begins as a slow negative feedback loop during step 3 as well as happens because the original signaling cell was degraded by a degradation enzyme.

source, transduction, change in gene expression (turn on/off a gene), termination

The law stating energy cannot be created or destroyed, but can change form, is known as ____.

the first law of thermodynamics

active site

the site of an enzyme that is complementary in shape to the substrate that enzyme binds

Which of the following are true about the above essential amino acid structure? Choose all that apply

this amino acid is non-polar, and this amino acid cannot be made by a human cell