Biology 201 Final Review

The processing and packaging of secretory proteins specifically occur in the Golgi apparatus. The Golgi apparatus is an organelle found in eukaryotic cells that plays a crucial role in modifying, sorting, and packaging proteins for transport to their final destinations. It receives proteins from the endoplasmic reticulum and modifies them by adding sugars, lipids, or other molecules. It then packages these modified proteins into vesicles for transport to various parts of the cell or for secretion outside the cell. Therefore, the Golgi apparatus is the correct answer for this question.

The protons are concentrated in the intermembrane space of mitochondria by the energy produced from electron flow through the electron transport system. This process occurs during oxidative phosphorylation, where electrons are passed along a series of protein complexes in the inner mitochondrial membrane. As electrons are transferred, protons are pumped from the mitochondrial matrix into the intermembrane space, creating a concentration gradient. This gradient is then used by ATP synthase to generate ATP, the energy currency of the cell. Therefore, the correct answer is the intermembrane space of mitochondria.

During photosynthesis, ATP is indeed produced through both cyclic and non-cyclic electron flow. In cyclic electron flow, ATP is generated through a cyclic pathway of electron transfer, while in non-cyclic electron flow, ATP is produced through a linear pathway involving both photosystem I and photosystem II. Therefore, the statement is true.

The mRNA sequence GCA corresponds to the tRNA anticodon CGU. In the process of translation, the tRNA anticodon pairs with the mRNA codon, allowing the correct amino acid to be added to the growing polypeptide chain. In this case, the tRNA with the anticodon CGU will recognize and bind to the mRNA with the codon GCA, ensuring the correct amino acid is added.

Cytochrome c is a protein involved in the electron transport chain of cellular respiration. It plays a crucial role in transferring electrons from one enzyme complex to another. The inner membrane space of mitochondria is the location where the electron transport chain occurs. This space is between the inner and outer membranes of the mitochondria. Therefore, it is logical to conclude that cytochrome c is located in the inner membrane space of mitochondria, where it can carry out its function in the electron transport chain.

When you drink many liters of water in a short period of time, the body fluids become less concentrated than the fluid inside your cells. This creates a concentration gradient, causing water to enter the cells in an attempt to balance the concentration. As a result, the cells swell up. This can lead to a condition called water intoxication or hyponatremia, which can cause symptoms such as nausea, headache, confusion, seizures, and in severe cases, even coma or death.

The backbone of nucleic acids consists of a phosphodiester bond between the 3' and 5' functional groups of neighboring sugars. This is because nucleic acids, such as DNA and RNA, are composed of repeating units called nucleotides. Each nucleotide is made up of a sugar molecule (deoxyribose or ribose), a phosphate group, and a nitrogenous base (adenine, guanine, cytosine, or thymine/uracil). The phosphodiester bond forms between the 3' carbon of one sugar and the 5' carbon of the next sugar, creating a sugar-phosphate backbone that provides stability to the nucleic acid structure.

Facilitated diffusion is a passive transport process where molecules move across a membrane from an area of higher concentration to an area of lower concentration with the help of specific transport proteins. This allows molecules that are too large or polar to passively diffuse through the lipid bilayer to still move across the membrane. Therefore, the statement "Molecules move from a high concentration to a low concentration" is true for facilitated diffusion.

Solar energy collected by a plant is used to create charge separation in antenna and necessary pigments. This energy is collected by photosystem complexes that contain special chlorophyll molecules. These chlorophyll molecules are responsible for absorbing light and converting it into chemical energy through a process called photosynthesis. Therefore, the correct answer is that solar energy is collected by photosystem complexes containing special chlorophyll molecules.

Lipid synthesis and detoxification of drugs occur in the smooth endoplasmic reticulum. This organelle is responsible for the production of lipids, such as phospholipids and cholesterol, which are essential components of cell membranes. Additionally, the smooth endoplasmic reticulum plays a crucial role in detoxifying drugs and harmful substances by modifying them to make them more water-soluble and easier to excrete from the body. Therefore, the smooth endoplasmic reticulum is a specialized site for lipid synthesis and drug detoxification within the cell.

ATP hydrolysis provides the energy that drives the attachment of amino acids to the appropriate tRNA. ATP is a high-energy molecule that releases energy when it is broken down into ADP and inorganic phosphate through hydrolysis. This released energy is used to power various cellular processes, including the attachment of amino acids to tRNA molecules during protein synthesis. The energy from ATP hydrolysis allows the aminoacyl-tRNA synthetase enzymes to catalyze the formation of an ester bond between the amino acid and the tRNA molecule, ensuring accurate pairing and attachment of the correct amino acid to the appropriate tRNA.

The correct answer is the innermembrane space of mitochondria. The majority of the components of the mitochondrial electron transport system are located in the innermembrane space of mitochondria. This is where the electron transport chain takes place, which is a series of protein complexes that transfer electrons and generate ATP. The innermembrane space is highly folded, creating a large surface area for the electron transport system to occur. This compartmentalization allows for efficient energy production in the form of ATP.

Succinate dehydrogenase is an enzyme involved in the reduction of FAD (flavin adenine dinucleotide). It is known to be located in the inner membrane space of mitochondria. This is the space between the inner and outer membranes of the mitochondria. The inner membrane space plays a crucial role in the electron transport chain and oxidative phosphorylation, where succinate dehydrogenase participates. Therefore, it is logical to conclude that succinate dehydrogenase is located in the inner membrane space of mitochondria.

The correct answer is "All cells have a membrane-bound nucleus." This is because not all cells have a membrane-bound nucleus. Prokaryotic cells, such as bacteria, do not have a nucleus. They have a nucleoid region where their genetic material is located, but it is not surrounded by a membrane. The other statements are all tenets of the cell theory, which state that the cell is the basic unit of structure for all organisms, all cells arise from preexisting cells, and all organisms consist of one or more cells.

Both prokaryotes and eukaryotes use translation of mRNA in the 5' to 3' direction to synthesize proteins. This process involves the ribosomes reading the mRNA sequence and assembling the corresponding amino acids to form a polypeptide chain. Additionally, both prokaryotes and eukaryotes undergo semi-conservative replication of DNA during cell division. This process ensures that each new DNA molecule formed contains one original strand and one newly synthesized strand.

Antarctic fish would be predicted to have the highest percentage of unsaturated phospholipids in their cell membrane. This is because unsaturated phospholipids have double bonds in their fatty acid chains, which provide fluidity and flexibility to the cell membrane. In the cold temperatures of the Antarctic, maintaining a fluid cell membrane is crucial for the survival of organisms. Therefore, Antarctic fish, which inhabit extremely cold environments, would have a higher proportion of unsaturated phospholipids in their cell membranes compared to the other organisms listed.

The given information states that the pigment congregates between an aqueous environment and a hydrophobic environment and creates a blue ring around the oil droplets when added to a mixture of oil and water. This suggests that the pigment has both hydrophilic and hydrophobic properties, allowing it to interact with both water and oil. Therefore, the pigment is considered to be amphipathic, meaning it has both polar and nonpolar regions.

The Calvin Cycle involves the reduction of carbon dioxide to form organic sugars. This process takes place in the stroma of plant cells, not in the cytosol. ATP is used to phosphorylate glucose and trap it in the stroma, not the cytosol. The Calvin Cycle can occur during the day as well as at night. It does not utilize the oxygenase activity of RUBISCO to generate useful cycle intermediates.

Cellulose is a complex carbohydrate and a major component of plant cell walls. It is made up of repeating units of glucose monomers, which are monosaccharides. Therefore, the mismatched pair in the given options is Cellulose - Amino Acid.

Ubiquitination is a post-translational modification process where a ubiquitin molecule is attached to a protein. This modification plays a crucial role in protein degradation, protein trafficking, and protein localization within the cell. Therefore, ubiquitination directly affects the protein product rather than DNA or RNA.

Enzymes are biological catalysts that speed up chemical reactions in living organisms. They do this by binding to substrates, the molecules that participate in the reaction, in a way that allows them to come together and form the desired product more easily. This binding process lowers the activation energy required for the reaction to occur, making it more likely to happen. Additionally, enzymes are sensitive to changes in temperature and pH, as these factors can affect the enzyme's structure and therefore its ability to function properly.

The given chemical reaction has an equilibrium constant that is less than 1 under standard conditions, which indicates that the reaction favors the formation of reactants rather than products at equilibrium. This means that the reaction is not spontaneous in the forward direction and requires energy for the reaction to proceed under standard conditions. Since the reaction requires energy, it cannot occur spontaneously in a cell.

The answer choices provide different units of measurement that are equivalent to one meter. The correct answer is "10^6 micrometers" because one meter is equal to 10^6 micrometers. Similarly, "1*10^9 nm" is also correct as it represents one meter in nanometers. The other answer choices, 10 cm and 10000 mm, are not equivalent to one meter but are commonly used as smaller units of measurement.

The correct answer is RNA, Ca2+, glucose, water, ethanol, N2. This is because the order of permeability in a lipid bilayer is determined by the size and charge of the molecules. RNA is the least permeable as it is a large molecule with a negative charge. Ca2+ is next because it is a small, positively charged ion. Glucose is larger than water and ethanol, so it is less permeable than them. Water is smaller than ethanol and N2, so it is more permeable than them. Ethanol is smaller than N2, so it is more permeable than N2.

Disulfide bonds are covalent bonds formed between two cysteine residues in a protein. These bonds play a crucial role in stabilizing the tertiary structure of proteins. The tertiary structure refers to the three-dimensional arrangement of the protein's secondary structure elements, such as alpha helices and beta sheets. Disulfide bonds can form between different regions of the protein chain, bringing them closer together and providing additional stability. Therefore, the correct answer is "Tertiary."

Topoisomerase is the correct answer because it is an enzyme that is responsible for catalyzing the interconversion of relaxed and supercoiled DNA. It achieves this by making transient breaks in the DNA strand, allowing it to relieve the tension and supercoiling that can occur during DNA replication and transcription. Helicase, ligase, polymerase, and hydrolase are all enzymes involved in DNA replication and repair, but they do not specifically catalyze the interconversion of relaxed and supercoiled DNA like topoisomerase does.

The given DNA sequence is 30 nucleotides long. Each codon consists of 3 nucleotides, so there will be a total of 10 codons in the sequence (30 nucleotides / 3 nucleotides per codon). However, one codon is the start codon and another codon is the stop codon, which do not code for amino acids. Therefore, there will be 10 - 2 = 8 codons that code for amino acids. Since each codon codes for one amino acid, there will be a total of 8 amino acids in the peptide.

The number of different amino acid sequences that could be coded for a peptide-coding DNA sequence that is 36 nucleotides long can be calculated by taking the number of possible nucleotides (4) and raising it to the power of the number of codons (3) in the sequence. This is because each codon consists of three nucleotides and can code for one amino acid. Therefore, the correct answer is 4^3, which is equal to 10^20.

The primary structure of a protein refers to the linear sequence of amino acids that are linked together by peptide bonds. This sequence is important because it determines the secondary and tertiary structure of the protein. Additionally, the primary structure remains unchanged during denaturation, which is the process of unfolding or altering the protein's shape. Therefore, the correct answer is "all of the above" because all of these statements are true regarding the primary structure of a protein.

The question asks which properties/characteristics are the same for both simple diffusion and active transport. However, none of the given options (direction of solute movement relative to concentration gradient, metabolic energy requirement, involvement of integral membrane proteins) are shared between these two membrane transport mechanisms. Therefore, the correct answer is "None of these are shared".

When the bacterial culture is transferred from 37C to 25C, the decrease in temperature causes an initial decrease in membrane fluidity. This is because the lower temperature reduces the kinetic energy of the phospholipid molecules, causing them to pack more tightly together and become less fluid. Additionally, the lower temperature promotes the gradual insertion of membrane phospholipids that have unsaturated fatty acid chains. Unsaturated fatty acids have kinks in their structure due to the presence of double bonds, which prevents the phospholipids from packing tightly together. This increases membrane fluidity and helps to maintain the integrity and functionality of the bacterial cells.

Acetyl CoA from fat metabolism can enter the citric acid cycle. This is because during fat metabolism, fatty acids are broken down into Acetyl CoA molecules, which can then be used as a fuel source in the citric acid cycle. This allows for the generation of energy through the oxidation of Acetyl CoA and the subsequent production of ATP.

In the "light-dependent" reactions of photosynthesis, the electrons that reduce PSII come from water. This is known as photolysis, where water molecules are split into oxygen, protons, and electrons. These electrons are then transferred to PSII to replace the ones that were lost during photosystem I (PSI) electron transport. Additionally, the ATP synthase enzyme uses the energy from the proton gradient across the thylakoid membrane to produce ATP in the stroma. This process is known as chemiosmosis, where the movement of protons through ATP synthase drives the synthesis of ATP.

ATP is the correct answer because it is a high-energy molecule that acts as a regulator of pyruvate dehydrogenase. ATP binds to an allosteric site on the enzyme, causing a conformational change that inhibits its activity. This regulation helps to prevent the excessive production of ATP when energy levels are already high. CoA, glucose, pyruvate, and NAD+ are not allosteric inhibitors of pyruvate dehydrogenase.

Some organisms are capable of carrying out the overall reverse reaction of glycolysis. This means that instead of breaking down glucose into pyruvate and producing ATP, these organisms can convert pyruvate back into glucose and consume ATP in the process. This is known as gluconeogenesis and allows these organisms to synthesize glucose when it is not readily available in their environment.

Both facilitated diffusion and active transport involve integral membrane proteins. In facilitated diffusion, these proteins help in the passive movement of solutes across the membrane, while in active transport, they actively transport solutes against their concentration gradient using energy. The direction of solute movement relative to the concentration gradient and the requirement of metabolic energy are different for these two mechanisms.

Glucose is a carbohydrate, which means its molecular formula follows the (CH2O)n pattern. This pattern indicates that glucose is composed of carbon, hydrogen, and oxygen atoms in a specific ratio. Additionally, glucose can form glycosidic bonds with other monosaccharides through condensation reactions. This allows glucose to combine with other sugars to form larger carbohydrate molecules. Lastly, glucose polymers can exist in either linear or branched forms, meaning that the glucose molecules can be arranged in a straight chain or have side branches.

The process of transcription involves the synthesis of RNA from a DNA template. It is not bidirectional, as it only occurs in one direction from the 3' to 5' end of the DNA strand. It is also not conservative, as it results in the production of a new RNA molecule rather than conserving the original DNA molecule. Transcription does occur during the S phase of the cell cycle, as this is when DNA replication takes place and the DNA template is available for transcription. Additionally, transcription requires RNA polymerase, an enzyme that catalyzes the formation of RNA molecules.

The regulation of gene expression through cleavage in eukaryotes can work directly on DNA, RNA, and the protein product. This means that the process of cleavage can affect the DNA sequence, the RNA molecule, and the final protein product that is produced from the gene. Cleavage can involve the cutting or modification of DNA, the splicing or processing of RNA, and the degradation or modification of the protein product.

The alpha helix and beta sheet structures in proteins are formed by hydrogen bonding between atoms of the polypeptide backbone. This backbone consists of repeating units of amino acids, and the hydrogen bonds form between the carbonyl oxygen of one amino acid and the amino hydrogen of another amino acid. These hydrogen bonds stabilize the secondary structures of proteins and play a crucial role in their folding and stability.

In oxidative phosphorylation, electron transport and ATP synthesis are coupled, meaning they occur together and are dependent on each other. During electron transport, electrons are passed along a series of proteins in the inner mitochondrial membrane, creating a proton gradient. This proton gradient is then used by ATP synthase, which acts as a proton pump, to concentrate protons on one side of the membrane. The flow of protons back across the membrane through ATP synthase provides the energy needed to convert ADP to ATP, resulting in the production of ATP. Additionally, more ATP is produced per FADH2 oxidized compared to NADH oxidized during this process.

Adenosine is a nucleoside that is classified as a purine. It is composed of a sugar group, a phosphate group, and a nitrogenous base. Adenosine lacks a hydroxyl group on the 3' carbon. In RNA, Adenosine base pairs with Uradine.

Metal ions serve as electron acceptors and donors in some of the electron transfer reactions. This is because metal ions can easily gain or lose electrons due to their electronic structure, making them suitable for accepting or donating electrons in redox reactions. This property of metal ions is utilized in various biological processes, such as in the electron transport chain, where metal ions like iron and copper play crucial roles in accepting and donating electrons to facilitate energy production.

The oxidation of malate during the citric acid cycle requires NAD+, which suggests that the enzyme catalyzing this reaction is a dehydrogenase. This reaction occurs in the mitochondrial matrix, which is where the citric acid cycle takes place. Additionally, the fact that NADH produced in this reaction gives its electrons to ADP to form ATP indicates that this reaction is part of the electron transport chain and oxidative phosphorylation, which occur under aerobic conditions. Therefore, this reaction does not occur under anaerobic conditions.

In co-translational import of polypeptides across the ER membrane, the translation of the polypeptide begins in the cytosol. This means that the synthesis of the polypeptide chain starts outside of the ER. GTP hydrolysis facilitates the process, indicating that the energy provided by GTP hydrolysis is necessary for the import of the polypeptide into the ER. This suggests that GTP hydrolysis is involved in the translocation of the polypeptide across the ER membrane.

A spontaneous reaction will always have a negative value of Delta-G because Delta-G represents the change in Gibbs free energy, which is a measure of the available energy to do work in a system. A negative value of Delta-G indicates that the reaction releases energy and is thermodynamically favorable. However, a spontaneous reaction could still take a very long time to occur, depending on factors such as the activation energy and the presence of catalysts.

Changes in location refers to the movement of a gene or its product to a different cellular compartment. In eukaryotes, this regulation primarily works directly on RNA and the protein product. RNA molecules can be transported from the nucleus to the cytoplasm, where they undergo translation to produce proteins. The proteins can also be targeted to specific organelles or cellular structures based on signals present in the protein itself. Therefore, changes in location involve the direct regulation of RNA molecules and the resulting protein product.

Regulation of gene expression in eukaryotes can occur through binding by regulatory proteins. These proteins can directly interact with DNA, RNA, or the protein product to control gene expression. In this case, the regulatory proteins can bind directly to DNA, RNA, or the protein product to regulate the expression of genes.

Both products of ATP hydrolysis have resonance stabilization because the products, ADP and inorganic phosphate (Pi), have stable resonance structures that contribute to their stability. ATP production is highly exergonic, meaning it releases a large amount of energy when hydrolyzed. ATP and Coenzyme A have some common structural features, such as the presence of a phosphoanhydride bond, which is important for their energy transfer functions.

During the preparation of pyruvate for the citric acid cycle, a dehydrogenase enzyme located in the mitochondrial matrix catalyzes the reactions. This enzyme helps in the conversion of pyruvate into a substrate for the citric acid cycle. This conversion ultimately leads to the production of three ATP molecules per pyruvate converted into the citric acid cycle substrate. Additionally, during these reactions, Coenzyme A-SH picks up an acyl group from pyruvate, further facilitating the process.