Human Biology, Chemistry, Cell Structure & Function Flashcards
What are the levels of organization in human biology?
-atom/molecule -cell -tissue -organ -organ system -organism -population -community -ecosystem -biosphere
List/Describe the Characteristics of Living Things
- different molecular composition
- require energy and raw materials
- composed of cells
- maintain homeostasis
- respond to external environment
- grow and reproduce
*populations of living things evolve
Parts of Scientific Method/ How it Works
- ) observe and generalize(inductive reasoning): make generalizations based on observations about the world
- ) formulate a hypothesis: statement that can lead to testable deductions (can be tested)
- ) make a testable prediction: what could happen
- ) experiment or observe: manipulation of natural world to test prediction
- ) modify hypothesis/ repeat steps 3 & 4
What is science/scientific theory?
- Science: the study of the natural world
- Scientific Theory: broad hypothesis that has been extensively tested and supported over time
What is a Controlled Experiment/Test Group/Control Group?
- Controlled Experiment: all possible variables are controlled so they cannot affect the outcome
- Test Group: group that receives the variable being tested
- Control Group: group that does not receive the variable being tested
Define: Hypothesis/Theory/Experiment
- Hypothesis: a statement that can lead to testable deductions
- Theory: a broad hypothesis that has been extensively tested and supported over time and explains a broad range of scientific facts with a high degree of reliability
- Experiment: a carefully planned and executed manipulation of the natural world to test your prediction
Define:Conclusion/Observation/Data
- Conclusion: a judgment or decision reached by reasoning
- Observations: observing someone or something carefully in order to gain information
- Data: numerical information that can be organized and interpreted
Define: Variable/Experimental Group/Control Group/Placebo
- Variable: factors that might vary during the course of an experiment
- Experimental Group: the group of subjects that receives the experimental treatment
- Control Group: undergo all the steps in an experiment except for the one being tested
- Placebo: “false treatment”
Define: Metabolism/Cell/Homeostasis
- Metabolism: the physical and chemical process involved in transforming energy and molecules so that life can be sustained
- Cell: smallest unit of life that exhibits all characteristics of life
- Homeostasis: the maintenance of a relatively constant internal environment
Define: Atom/Proton/Neutron/Electron
- Atom: the smallest unit of any element that still retains the physical and chemical propertires of that element
- Proton: positively charged subatomic particle in the nucleus of an atom
- Neutron: uncharged subatomic particle found in the atomic nucleus
- Electron: Negatively charged subatomic particle/ orbit the atoms nucleus
Define: Molecule/Compound/Ionic Bond/Ion
- Molecule: particle consisting of two or more atoms joined together by chemical bonds
- Compound: when atoms are of different elements
- Ionic Bond: atoms that give up or take in electrons to achieve a stable outer shell
- Ion: atoms or molecules that have either positive or negative charge
Define: Covalent Bond/Polar Covalent Bond/Non Polar Covalent Bond
- Covalent Bond: electron sharing bond between atoms/the sharing of electrons between atoms results in each atom having a maximally filled outermost shell of electrons
- Polar Covalent Bond: pair of electrons is unequally shared between two atoms
- Non-Polar Covalent Bond: equal share of electrons between two atoms
Define: Isomer/Isotope/Monomer/Polymer
- Isomer: ions or molecules with identical formulas but distinct structures
- Isotopes: different atomic forms of the same element, varying only in the number of neutrons they contain
- Monomer: a molecule that can be bonded to other identical molecules to form a polymer
- Polymer: a substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together
Define: Macromolecule/Catalyst/Hydrogen Bond/Enzyme
- Macromolecule: a molecule containing a very large number of atoms, such as a protein, nucleic acid, or synthetic polymer
- Catalyst: a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change
- Hydrogen Bond: weakest of the bonds/attraction between seperate molecules
- Enzyme: are both proteins and biological catalysts. Catalysts accelerate chemical reactions
Use The Periodic Table to Diagram an Atom
*to find number of neutrons subtract atomic number from atomic mass
- Atomic #: number of protons (determines what element it is)
- Atomic Mass: protons + neutrons
How are atoms constructed/what are their components?
- atoms are the smallest units of any element that retains the physical and chemical properties of that element
- atoms are composed of electrons(-) , protons(+) , neutrons (neutral)
Location of Components on Atoms/ How and Why do Atoms Form Bonds?
- protons and neutrons are tightly bound together in nucleus/ electrons orbit the nucleus
- atoms form bonds to form molecules
chemical bond: interacting with one or more atoms to fill its outermost shell
Types of Chemical Bonds
- covalent bond:sharing electrons to fill outermost shell (strongest chemical bonds)
- ionic bond: bond between two oppositely charged ions
- hydrogen bond: bond between oppositely charged regions of molecules that contain covalently bonded hydrogen atoms (weakest)
What is the difference between bond polarity and molecular polarity?
The difference between Bond and Molecular Polarity is that bond polarity is the difference of electronegativity between electrons being bonded, and molecular polarity is the sum of these differences, in electronegativity.
Polar/Non-Polar Covalent Bonds Between Atoms
Molecule w/ Partial - & Partial + charges
*look up video on how to do so
What are the basic properties of water? Why are these important to life? How do hydrogen bonds influence these properties?
- liquid at room temperature (due to H bonds, can break down weak hydrogen bonds in this temp. range)
- universal solvent for polar molecules( polar molecules=hydrophilic, non-polar molecules= hydrophobic
- cohesion
- high heat of vaporization
- frozen water is less dense(repeating pattern of hydrogen bonds forms between adjacent water molecules)
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pH Scale W/ Acidic, Basic, and Neutral Regions/ How does H+ change with pH?
- [H+] is less abundant in basic and more abundant in acidic
- [OH-] is more abundant in basic and less abundant in acidic
What are the four major classes of macromolecules found in living things?/What are they made of?
- carbohydrates: Energy Storage- Monosaccharides(simple sugars) carbon/hydrogen/oxygen structure , Polysaccharides (linking simple sugars) Monosaccharides (dehydration synthesis)
- lipids: are hydrophobic Triglycerides are fats (1 glycerol &3 fatty acids)/Phopspholipids are modified lipids/primary structural component of cell membranes (1 glycerol & 2 fatty acids)
- proteins: constructed of amino acids (proteins have unique 3D structures)
- nucleic acid: store genetic info-DNA & RNA (constructed of nucleotides)
What is Dehydration Synthesis/Hydrolysis?
- Dehydration Synthesis (condensation reaction): macromolecules built inside the cell/ requires energy/ smaller molecules called subunits are joined by covalent bonds(sharing of electron pairs)/each time a subunit is added the equivalent of a water molecule is removed
- Hydrolysis: breakdown of macromolecules using water/ the equivalent of a water molecule is added each time a covalent bond between single subunits in the chain is broken (reverse of dehydration synthesis)
Four Different Levels of Protein Structure
- Primary: linear sequence
- Secondary: orientation in space
- Tertiary: twisting and folding into 3D shape
- Quaternary: two or more polypeptide chains linked together
Configuration and Properties of a Phospholipid/Why are Phospholipids Important?
- molecule of glycerol as the backbone and two fatty acid tails
- one end of the molecule is polar (dissolves in water) and the other end (the two fatty acid tails) is neutral and does not dissolve in water
- Phospholipids are important because they are the primary structural component of cell membranes
Components, Structure, Function of RNA & DNA
RNA: contains the instructions for producing proteins/shorter single strand of RNA nucleotides representing the code for one or more proteins
DNA: contains the intructions for producing RNA/ composed of two long strands of nucleotides (molecular subunits) intertwined into a double helix
What is ATP/ Why is it Important?
ATP: cell energy/universal energy source for cells
-anytime a cell needs energy for virtually any function it can break the bond between the outermost two phosphate groups of an ATP molecule
Define Active Transport/Passive Transport/Diffusion/Facilitated Transport
- Active Transport: cell moves against its concentration gradient/requires ATP or other source/requires membrane protein
- Passive Transport: transports a molecule without requiring the cell to expend energy/ high to low concentration
- Diffusion: movement of a molecule from a region of high concentration to a region of low concentration
- Facilitated Transport: passive transport of a substance into or out of a cell along a concentration gradient/requires a carrier protein
Define Osmosis/Sodium Potassium Pump
- Osmosis: diffusion of water across a selectively permeable membrane
- Sodium Potassium Pump: active transport protein of the plasma membrane that simultaneously transports three sodium ions out of the cell and two potassium ions in (important for maintaining cell volume and for generating the resting membrane potential
What is a receptor protein?/What does it trigger?
Receptor Protein: transmission of info to and from cell
- ) signaling molecule approaches receptor protein embedded in cell membrane
- ) bind to specific recptor site/ triggers a series of biochemical events that causes changes within the cell
- ) once signaling molecule detaches from receptor site, the reaction stops
Structures Found Inside Cell ( cytosol, peroxisome, centrioles, cytoskeleton)
- Cytosol: semifluid gel material inside the cell
- Peroxisome: destroys cellular toxic waste
- Centrioles: microtubular structures/involved in cell division
- Cytoskeleton: structural framework of the cell
Structures Found Inside Cell ( smooth ER, rough ER, golgi, secretory vesicles, ribosomes)
- Smooth ER: primary site of macromolecule synthesis other than proteins
- Rough ER: primary site of protein synthesis by ribosomes
- Golgi: refines, packages, and ships macromolecular products
- Secretory Vesicles: membrane-bound shipping container
- Ribosomes: site of protein synthesis
Structures Found Inside a Cell (plasma membrane, mitochondria, lysosomes, nucleus)
- Plasma Membrane: controls movement of material into and out of cell
- Mitochondria: produces energy for the cell
- Lysosomes: digests damaged organelles and debris
- Nucleus: information center (contains DNA)
