Lecture 1.2 and 1.3 Chemistry Review Flashcards
Explain covalent bonds
Bonds between two nonmetals where they share electrons
Function of contractile proteins and examples.
Allow shortening of muscle cells, which produces movement. Examples: myosin; actin.
What are the three ways pH is maintained in the body and in what order are they used?
- buffers
- respiratory system
- urinary system
Explain the sodium-potassium pump.
Also known at ATPase, it pumps sodium out of the cell and potassium into the cell. ATP powers this.
The Na⁺/K⁺-ATPase enzyme is active (i.e. it uses energy from ATP). For every ATP molecule that the pump uses, three sodium ions are exported and two potassium ions are imported; there is hence a net export of a single positive charge per pump cycle.
Function of adrenocortical hormones
Help regulate metabolism, resistance to stress, and salt and water balance.
Explain hydrogen bonding
Bonds between H and F, O, N that make a sandwich of either OHO or HOH. Most common between water molecules. Relies on polar covalent bonds.
What are the functions of regulatory proteins and their functions?
Function as hormones that regulate various physiological processes
-control growth and development
-as neurotransmitters, mediate responses of the nervous system.
Examples: the hormone insulin (regulates blood glucose level
the neurotransmitter known as substance P (mediates sensation of pain in the nervous system).
What are the four types of lipids not included in the other groups?
Carotenes, vitamin E, vitamin K, and lipoproteins
How are proteins formed?
The combination of amino acids bonded via peptide bonds.
Functions of fatty acids
Used to synthesize triglycerides and phospholipids or catabolized to generate adenosine triphosphate (ATP).
Catabolize: process (a substance) by the breakdown of complex molecules to form simpler ones, together with the release of energy
What are the 5 types of chemical reactions?
Synthesis, decomposition, exchange, reversible, and redox
examples of disaccharides and their composition
Formed by the combination of two monosaccharides by dehydration synthesis
sucrose= glucose+fructose
lactose= glucose+galactose
maltose= 2xglucose
What is the normal pH in the body?
7.35-7.45
How are peptide bonds formed and broken?
Via dehydration synthesis and hydrolysis
Explain ionic bonds
A bond between a cation and an anion in which one gains electrons and one loses electrons.
What types of molecules can be easily dissolved in water? Which cannot?
Easily dissolved, polar covalent compounds: proteins, nucleic acids, carbohydrates, and ATP
Cannot, nonpolar covalent bonds: lipids
What are the functions of structural proteins and examples?
Form structural framework of various parts of the body.
Examples: collagen in bone and other connective tissues; keratin in skin, hair, and fingernails.
What are the functions of enzymes?
Reduces activation energy needed and increases the rate of the reaction.
Explain how enzymes work
To catalyze a reaction, an enzyme will grab on (bind) to one or more reactant molecules. These molecules are the enzyme’s substrates.
In some reactions, one substrate is broken down into multiple products. In others, two substrates come together to create one larger molecule or to swap pieces.
The part of the enzyme where the substrate binds is called the active site (since that’s where the catalytic “action” happens).
Three important functions ATP is used for
active transport, movement, synthesis
What is the function of cholesterol?
Minor component of all animal cell membranes; precursor of bile salts, vitamin D, and steroid hormones.
What are the three markers of an organic compound?
Contains H, usually O, and has covalent bonds
What is the most important inorganic solution?
H2O
What are the functions of vitamin D?
Helps regulate the calcium levels in the body; needed for bone growth and repair.
