Bio Ch 4 Study Notes PDF

**[Bio exam 1 study module(same as quizlet terms):]** The chemical group that is involved in regulating DNA is the\_\_\_\_\_\_. Methyl group (-CH~2~ ) Which element is always associated with organic chemistry? Carbon. Carbon's atomic number is 6. This means that it has \_\_\_\_ electrons. After c...

**[Bio exam 1 study module(same as quizlet terms):]** The chemical group that is involved in regulating DNA is the\_\_\_\_\_\_. Methyl group (-CH~2~ ) Which element is always associated with organic chemistry? Carbon. Carbon's atomic number is 6. This means that it has \_\_\_\_ electrons. After completing the first energy level, carbon has \_\_\_\_ valence electrons and can form \_\_\_\_ bonds. 6; 4 ;4. The chemical group that helps stabilize protein structure is the \_\_\_\_\_\_. sulfhydryl group (-SH) Which of the following molecules is a weak base? R-NH~2~ in the pharmaceutical industry, two enantiomers of a drug\_\_\_\_\_\_. May not be equally effective When a double bond joins two carbon atoms,\_\_\_\_\_\_\_\_ can form. Cis-trans isomers. What is ATP's importance in the cell? ATP stores the potential to react with water, thereby removing a phosphate group and releasing energy for cellular processes. What are the six most important chemical elements of life? Carbon, nitrogen, oxygen, hydrogen, phosphate, and sulfur. Which chemical group is most likely to be responsible for an organic molecule behaving as a base? Amino. The chemical group that acts as an acid is\_\_\_\_\_. Carboxyl group (-COOH). Enantiomers are\_\_\_\_\_\_. Mirror -image isomers of a molecule. Which if the following molecules is a weak acid? R-COOH. Molecules that only contain carbon and hydrogen are calld\_\_\_\_\_\_\_. Hydrocarbons. Which of the following are properties of hydrocarbons? Hydrophobic, non-polar, and a good source of stored energy. When three phosphate groups are covalently attracted to adenosine, \_\_\_\_\_\_ is formed. ATP. Which of the following is found in all amino acids? Both -COOH and -NH~2~. Pharmaceutical companies are selling close to \$200 billion of single enantiomer-drugs. Why might it be important to use only one form of enantiomer? One enantiomer may provide an effective treatment whereas the other may be ineffective or even toxic. **[Bio post quiz(ch 1-4):]** Which of the following statements about ATP/ADP is true? ATP can have four negative charges. Out of hydroxyl, amino, and carboxyl; which group is most likely to gain a proton? Amino. Because carbon has a valence of four, it can form four covalent bonds with other atoms. Such versatility of carbon allows for building the skeletons of organic molecules, including important biomolecules. How do isomers differ from one another? Isomers differ in the arrangement or bonding of atoms. Which of the following best describes cis-trans isomers? They differ in their spatial arrangement around inflexible double bonds. Variation in carbon chains is an important source of molecular complexity. How can carbon skeletons vary? Carbon skeletons can vary in length, exhibit different branching structures, contain double bonds at different positions, and contain rings of carbon atoms. **[Bio Ch 1-4 hw:]** L-dopa is used to treat \_\_\_\_\_. Parkinson\'s disease. What kind of effect does R-dopa have on Parkinson\'s disease? None. **[Bio Ch 1-4 notes:]** Organic phosphate \_\_\_\_\_. Contributes negative charge. Amine \_\_\_\_ acts as a base. Thiol \_\_\_\_\_. Forms disulfide bonds. Aldehyde \_\_\_\_. May be a structural isomer of a ketone. Carboxylic acid\_\_\_\_. Acts as an acid. Alcohol \_\_\_\_\_. Is polar and makes compounds more soluble in water. Hydroxyl groups are characteristics of alcohol. The electronegativity of nitrogen means that amino groups tend to pick up hydrogen ions. Thiols are characterized by the presence of a sulfhydryl group. Phosphate groups are a component of ATP. By donating hydrogen ions, carboxyl groups act as an acid. **[Other:]** What is the structure of a methyl group? A carbon atom bonded to three hydrogen atoms, with the fourth bond available for attachment to a larger group. What role does methylation play in gene expression? it suppresses gene expression, preventing certain genes from being expressed in cells. How many chromosomes do humans have? 46 chromosomes Are all genes expressed in every cell? No, only a small subset of genes is expressed in any given cell, depending on the cell type. What is the role of acetyl groups in gene expression? They un regulate or activate gene expression, turning on specific genes. Why is ATP considered the type of cellular energy? It is the primary energy currency of the cell, providing the energy needed to fuel cellular processes. How is energy harvested from food related to ATP? Energy from food must be converted into ATP for it to be usable by cells for various functions. What happens to ATP in the presence of water? It can lose one phosphate group, converting into ADP and releasing energy. What does ADP stand for? Adenosine diphosphate, which is formed when ATP loses one phosphate group. What is the difference between high energy and low energy in the context of ATP? High energy refers to ATP, which has stored energy in its phosphate bonds, while low energy refers to ADP, which has less energy after one phosphate bond is broken. What is meant by inorganic phosphate? It is a phosphate that is not attached to a carbon-containing molecule, as seen when ATP converts to ADP. What is the molecular mass of a molecule? The sum of the atomic masses of all the atoms in the molecule. What is a mole? A unit that measures the number of molecules, specifically 6.02 x 10 ^23^ molecules. How do you measure the mole of a substance? Measure the substance's mass that corresponds to its molecular mass in grams and dissolve it in a specific volume of solvent, usually water. What is molarity? The concentration of a solution expressed as the number of moles of solute per liter of solution. How do you calculate the molecular mass of nickel sulfate? You add the atomis masses of nickel, sulfur, and four oxygens to get a total molecular mass. What is the formula weight of water? 18 grams What is the relationship between pH and hydrogen ion concentration? The pH scale measures the concentration of hydrogen ions; a lower pH indicates higher hydrogen ion concentration and greater acidity. What defines an acid and a base in biological terms? An acid is a substance that donates hydrogen ions to a solution, while a base is a substance that accepts hydrogen ions drom a solution. What is the significance of strong and weak acids? Strong acids dissociate completely in solution, while weak acids only partially dissociate, allowing for reversible reactions. How is the pH scale structured? The pH scale ranges from 0 to 14, with 7 being neutral. A pH less than 7 indicates acidity, while a pH greater than 7 idicates basicity. What is the dissociation constant of water at 25 degrees celsius? The dissociation constant of water is 10^-14^, meaning the concentrations of hydrogen ions and hydroxide ions are equal in pure water. What is the role of buffers in biological terms? Buffers minimize in pH by either donating or accepting hydrogen ions, helping to maintain stable conditions in biological environments. What are hydrocarbons? Organic compounds consisting only of hydrogen and carbon, typically forming long chains or rings. What are structural isomers? Compounds that gave the same molecular formula but different arrangements of atoms, resulting in different properties. What is the difference between cis and trans isomers? Cis isomers have substituents on the same side od a double bonds, while trans isomers have them on opposite sides, affecting their chemical properties. What is a dilsulfide bridge? An important bond that helps hold DNA in its higher order shape, involving sulfur atoms. What are phosphate groups usually known from? Phosphate groups are commonly known from ATP (adenosine triphosphate) and ADP (adenosine diphosphate). What elements make up a phosphate group in ATP? One phosphorus atom and four oxygen atoms, with one oxygen being double bonded.