Human Morphology & Function I: Biochemistry & Cell Biology

Question: What is an atom?

Answer: Smallest particle of matter that still retains properties of an element

Question: What are the subatomic particles of an atom?

Answer: Protons, electrons, and neutrons

Question: What is the charge of a proton?

Answer: Positive (+)

Question: What is the charge of an electron?

Answer: Negative (-)

Question: What is the charge of a neutron?

Answer: Neutral

Question: Which part of an atom is always the same?

Answer: Number of protons

Question: What are isotopes?

Answer: Atoms with different numbers of neutrons

Question: What are ions?

Answer: Atoms with different numbers of electrons

Question: What determines an ion's charge?

Answer: How many electrons they have

Question: How are ionic bonds formed?

Answer: By exchanging electrons to fill outer electron shell

Question: What holds atoms together in an ionic bond?

Answer: Electrostatic attraction from positive to negative

Question: How are covalent bonds formed?

Answer: By sharing electrons to fill outer electron shell

Question: What is formed when atoms share electrons via covalent bonds?

Answer: Molecules

Question: What are molecules?

Answer: Multiple atoms bonded together by covalent bonds

Question: What constrains molecular arrangements?

Answer: How many bonds each atom can form, based on number of electrons

Question: What determines whether a molecule is polar or non-polar?

Answer: How electrons are shared

Question: What are polar molecules composed of?

Answer: Predominantly polar bonds

Question: What are non-polar molecules composed of?

Answer: Primarily non-polar bonds

Question: What leads to intermolecular interactions based on charge?

Answer: Polar or non-polar molecular properties

Question: What are biological macromolecules?

Answer: Large organic molecules synthesized by the body and essential for life

Question: What elements are always contained in biological macromolecules?

Answer: Carbon, Hydrogen, and Oxygen

Question: What additional elements may biological macromolecules contain?

Answer: Nitrogen, Phosphorus, or Sulfur

Question: Into how many categories are biological macromolecules grouped?

Answer: Four categories

Question: What are the four categories of biological macromolecules?

Answer: Lipids, Carbohydrates, Nucleic Acids, and Proteins

Question: What are lipids?

Answer: Fatty, water-insoluble molecules

Question: What are the key functions of lipids?

Answer: Store energy, compose cellular membrane, hormones

Question: What are the four main classes of lipids?

Answer: Triglycerides, phospholipids, steroids, and eicosanoids

Question: What are the functions of triglycerides?

Answer: Long-term energy storage, cushioning

Question: What types of triglycerides exist?

Answer: Saturated, unsaturated, polyunsaturated

Question: What is the function of phospholipids?

Answer: Form membranes, including plasma membrane for cells

Question: What is the structure of a phospholipid?

Answer: Polar head, non-polar tail

Question: What is a carbohydrate structurally?

Answer: Hydrated carbon, typically made up of repeating Carbons bound to an -H and an -OH

Question: What are the key functions of carbohydrates?

Answer: Energy source and storage

Question: What is glucose?

Answer: Primary energy source

Question: What is glycogen?

Answer: Polysaccharide of glucose for storage

Question: What is ribose?

Answer: Key component of nucleic acids

Question: What is starch?

Answer: Glucose polysaccharide, energy source

Question: What is cellulose?

Answer: Glucose polysaccharide, fiber

Question: What is the primary function of nucleic acids?

Answer: Store and transfer genetic information

Question: What are the important nucleic acids mentioned in the text?

Answer: DNA, RNA, and ATP

Question: How are monomers linked to form DNA and RNA polymers?

Answer: By phosphodiester bonds

Question: How many different proteins exist in the body?

Answer: 50,000 different proteins

Question: What groups make up an amino acid?

Answer: Amine, carboxylic acid, and R group

Question: How are amino acid monomers linked together?

Answer: By peptide bonds

Question: What is an oligopeptide?

Answer: 3-20 amino acids

Question: What is a polypeptide?

Answer: More than 20 amino acids

Question: What are glycoproteins?

Answer: Proteins with carbohydrates attached

Question: What are the four classes of amino acids?

Answer: Polar, non-polar, charged, special function

Question: What do the amino acid classes contribute to?

Answer: Structure and folding of the protein

Question: What is the primary structure of a protein?

Answer: Amino acid sequence

Question: What is the secondary structure of a protein?

Answer: Alpha helix, beta sheets

Question: What is tertiary structure in proteins?

Answer: Three-dimensional folding structure of a protein

Question: What is quaternary structure in proteins?

Answer: Association of multiple protein subunits

Question: What is denaturation?

Answer: Protein unfolding due to excessive heat, acidity, etc. that interferes with protein structure

Question: What are enzymes?

Answer: Special class of proteins that facilitate chemical reactions with lower energy input

Question: Can enzymes denature?

Answer: Yes, under unideal conditions

Question: What is cellular respiration?

Answer: Metabolic pathway in which enzymes break down organic molecules to form ATP

Question: Which organic molecules are broken down during cellular respiration?

Answer: Glucose, fatty acids, amino acids

Question: What do cells make up?

Answer: All living organisms and the tissues within our bodies

Question: What specific cell type is the focus of the lecture?

Answer: Human cell

Question: What do cells have that help cellular function?

Answer: Standard components

Question: What are the functions of the plasma membrane?

Answer: Physical barrier, regulate entry and exit, generate electrochemical gradients, communication

Question: What is the largest component of the plasma membrane?

Answer: Phospholipids

Question: Why do phospholipids form a bilayer?

Answer: Due to polar heads and nonpolar tails

Question: What does the phospholipid bilayer prevent?

Answer: Dissolution in water

Question: When added to water, what can phospholipids form?

Answer: Surface coat, micelles & bilayers

Question: What are the key characteristics of phospholipid membranes?

Answer: Separate aqueous compartments, impermeable to charged molecules, permeable to small uncharged molecules

Question: Which charged molecules are impermeable to phospholipid membranes?

Answer: Na+, Cl-, K+

Question: Which molecules are permeable to phospholipid membranes?

Answer: Small uncharged molecules like CO2, O2, NH3, H2O

Question: What is diffusion?

Answer: Movement of molecules down a concentration gradient

Question: What kind of movement characterizes diffusion?

Answer: Random movement

Question: What law governs the velocity of diffusion?

Answer: Ficke's law

Question: What is related to the rate of diffusion across a membrane?

Answer: Membrane resistance

Question: What is osmosis?

Answer: A type of diffusion in which water moves across a semi-permeable membrane in response to solute concentration gradient

Question: What condition must be met for osmosis to occur regarding membrane permeability?

Answer: Membrane must be more permeable to water than the solute

Question: What are osmoles?

Answer: Number of particles in a solution

Question: How are osmoles typically measured in the body?

Answer: In milliosmoles (1 osm = 1000 mOsm)

Question: How many osmoles does glucose in solution produce?

Answer: 1 osm

Question: How many osmoles does NaCl in solution produce?

Answer: 2 osm (Na+, Cl-)

Question: What is osmolarity?

Answer: Osmoles per liter of solution

Question: What is osmolality?

Answer: Osmoles per kilogram of solvent

Question: What is tonicity?

Answer: The way in which a solution outside a cell affects a cell's volume via osmosis

Question: What is the osmolarity of an isotonic solution?

Answer: 300 mOsm

Question: What is the osmolarity of a hypertonic solution?

Answer: > 300 mOsm

Question: What is the osmolarity of a hypotonic solution?

Answer: < 300 mOsm

Question: What happens to cells in a hypertonic solution?

Answer: Cells shrink - crenation

Question: What happens to cells in a hypotonic solution?

Answer: Cells swell - lysis

Question: What model describes the structure of plasma membrane proteins?

Answer: Fluid-mosaic model

Question: What are integral proteins?

Answer: Proteins embedded within the membrane

Question: What domains dominate most integral proteins?

Answer: Alpha helical domains made of hydrophobic amino acids

Question: What are peripheral proteins?

Answer: Proteins not embedded in the membrane

Question: How do peripheral proteins bind?

Answer: Non-covalently bond with integral proteins

Question: What functions can plasma membrane proteins serve?

Answer: Transport, cell surface receptors, identity markers, enzymes, anchor sites

Question: What types of transport do membrane proteins perform?

Answer: Active or passive transport

Question: What do cell surface receptors do?

Answer: Bind to ligands and initiate cellular response

Question: Give an example of cell surface receptor function mentioned in the text.

Answer: Neurotransmitters from nerve cells bind to muscle cells causing contraction

Question: What are glycoproteins and glycolipids?

Answer: Oligosaccharide chains linked covalently to proteins or phospholipids

Question: What are the functions of glycoproteins and glycolipids?

Answer: Cell identity, cell adhesion, blood clotting

Question: What is the function of the rough endoplasmic reticulum?

Answer: Protein synthesis and peroxisome formation

Question: What is the function of the smooth endoplasmic reticulum?

Answer: Lipid synthesis and detoxification