Quiz 1 Terms Flashcards
Scientific Method
the process by which observations are questioned, hypotheses are created and tested, testable predictions are made, and critical experiments are carried out. From this conclusions are drawn.
Empirical
based on, or verifiable observation
Qualitative
Observation that is a recorded description
Quantitative
Observation that is numerical
Independent Variable (IV)
what can be changed / not dependent on something else
Dependent Variable (DV)
what is measured / the effect
Null Hypothesis
Assumes there is no effect between variables (H0)
Critical Experiments
these make an experiment where its results will eliminate on or more of your hypothesis
Placebo Effect
Thinking a substance has a positive effect on the body when it does not actually do anything
Replication
repeating a study so its results can be confirmed and lead to a less biased conclusion
Scientific Theory
something that is so well supported by multiple experiments and years of evidence that it is practically a fact
Biology
The study of living things that has given us tools for survival
Levels of Organization
- Atomic / Molecular
- Cellular / Cells
- Tissue
- Organ
- Organism
- Population
- Community
- Ecosystem
- Biosphere
Emergent properties
Properties that become apparent and result from various interacting components within a system but are properties that do not belong to the individual components themselves. The individual components within a system amount to or manifest the property that is emergent
Biotic
relating to or resulting from living things
Abiotic
physical rather than biological, not devised from living organisms
Homeostasis
the tendency toward a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes
Structure and Function
These interact because they are intrinsically related
Cell theory
- all living things are made from cells
- cells are the smallest unit of life
- new cells are always produced from existing cells
Unicellular
one cell
Multicellular
many cells
Unicellular Organisms
organisms that grow to a critical size and divide to form two identical daughter organisms
Multicellular Organisms
organisms that begin as a single cells which grow and divide many times before developing tissues and organs
Acute change
rapid change
Chronic change
change over time that can reverse
–> tan fading
Periodic change
changes that occur at regular intervals
–> seasons
Evolutionary change
changes to the DNA of certain populations
–> giraffe neck small to long
Developmental Change
change over lifespans, preprogrammed and irreversible
–> newborn to adult / caterpillar to butterfly
Basic biology
understanding living organisms to increase knowledge
–> examining DNA structure
Applied biology
solve practical problems but needs basic biology to perform applied biology
–> developing the DNA structure to identify genetic diseases
Scientific Method Steps
- Observations / Background Research
- Ask a question
- Formulate a hypothesis
- Derive a testable prediction(s)
- Test prediction(s) with experiments
- Analyze Data and draw conclusions
- Consistent or not
- refine and repeat (cycle back) - Communicate results
Correlation vs Causation
Subsequent observations or experiments can reject a hypothesis but never fully prove it is correct, only support it
Matter
any substance that takes up space and has physical mass (atoms) that is made up of elements, substances that can not be reduced to a more basic chemical structure by a chemical reaction
Compounds
Substances consisting of two or more elements that have been chemically combined in fixed ratios
Organic Matter
Constructs living organisms to convert energy, essential for life, and make up 96% of living matter (Carbon 18%, Oxygen (65%), Hydrogen (10%), Nitrogen (3%))
Trace Elements
Elements found in such small quantities that are required for certain chemical processes to occur
Atoms
composed of subatomic particles (protons, electrons, neutrons)
Protons
Positive electrical charge that is in the atoms nucleus and reveals the atomic number of an element
Electrons
Negative electrical charge located around the nucleus and will have the same number as protons
Neutrons
Neutral charge located in the atoms nucleus
Isotopes
When an atom has different number of neutrons (gained or lost). The charge will stay the same but the property changes.
Valence Electrons
The electrons in the outermost shell of an atom
Electron Shells
Concentric circles surrounding the nucleus (first holds 2, second holds 8, third holds 18)
Valence Shell
Outermost electron shell of any atom
Bonds
An arrangement where two atoms are positioned very close to one another and share / donate electrons
Molecule
When two atoms are bounded together by covalent bonds (the resulting structure)
Double Bond
When an atom forms multiple bonds
Electronegativity
Tendency for an atom or functional group to attract electrons towards itself. Unequal electron sharing results in slight difference in charge between the two atoms.
- more electronegative = more negative charge
- less electronegative = more positive charge
Electrons are not always equally shared by atoms in a covalent bond which leads to an unequal distribution of electric charge
- how many times the electrons circulate the electron shell
- high electronegativity (pull of electrons) means electrons spend more time around one shell over the other
Polar Covalent Bonds
Bonds between an electronegative atom and non-electronegative atom which causes them to have electrical polarity
Dipole
A pair of equal and oppositely charged or magnified poles separated by a distance
Non Polar Covalent Bond
Evenly shared electrons do not create polarity in electrical charge
Hydrogen Bonds
Temporary bonds formed between the slightly positive hydrogen atoms, formed by polar covalent bond, and the slightly negatively charged electronegative atom of an adjacent polar covalent molecule
Polar molecules containing hydrogen can exhibit hydrogen bonding. The hydrogen atom from a polar molecule (delta +) is attracted to an electronegative atom of another polar molecule.
Van Der Waals interactions
weak attractions between atoms caused slight fluctuations in positioning of electrons that individually do not create strong forced to hold atoms together. When there is a lot, stronger attraction can occur.
Ionic Bond
The attraction between two oppositely charged atoms in a molecule. When an atom donates their electron to another atom and makes both atoms charged (ions)
- positive and negative attract
- break when they dissolve in water
Cations
positive ions
Anions
negative ions
Isomers
When two organic molecules vary only in their architecture (the way atoms are arranged in space)
Covalent Bond
When an atom shares their electron with another atom (non polar and polar)
- do not break when dissolved in water
Ions
When an atom is charged
Structural isomers
Two or more organic compounds have the same molecular formulas but different structures. Differ in which atoms are bonded together in the molecule. Have the same chemical formula but different bonding.
Cis-Trans Isomers
Pairs of molecules which have the same formula but functional groups are different orientations. Differ in placement of certain atoms in the molecule
Encantiomers
Mirror images of each other. Differ in their spatial arrangements of atoms around an asymmetric molecule.
Chemical reaction
When bonds are formed or broken because the bonds break and are replaced with a polar covalent bond and leaves a balanced equation.
Specific Heat
A substances ability to absorb energy without changing temperature
Solvent
Dissolving medium
Solute
Substance being dissolved
Solution
When a solute is dissolved in a solvent that can be important for conducting chemical reactions
Hydrophilic
water loving
- molecules with ionic or polar covalent bonds can dissolve in water
Hydrophobic
water hating / fearing
- hydrophobic molecules will cluster together
- non polar –> can’t dissolve in water
Carbon is … and can …
the backbone of all life and can bond to four other atoms
Macromoleules
Large molecules (Proteins, Lipids, Nucleic Acids, and Carbohydrates)
Polymers
long molecules (2+ monomers) that consist of several identical or repetitive smaller molecules called monomers linked by covalent bonds due to condensation
Monomers
a molecule that can be bonded to other identical molecules to form a polymer
Condensation Reactions
Dehydration, taking out a water molecule
Monomer –> polymer
Dimer
A chain of two monomers
Trimer
A chain with three monomers
Tetramer
A chain with four monomers
Hydrolysis Reactions
Adding water molecule
Polymer –> monomer
Carbohydrates
Sugar monomers combined to form long polymer chains that are usually composed of C, H, and O atoms. The carbon atoms are linked to a H atom, and/or a hydroxyl group (OH). They store energy and help with cell structure.
Monosaccharides
simple sugar monomers for carbohydrates
Pentose (5C)
- Ribose (C5H10O5)
- Deoxyribose (C5H10O4)
Hexoses (6C)
- Glucose (C6H12O6)
Disaccharides
two sugar monomers for carbohydrates
- Glucose + Fructose + Condensation = disaccharide
Polysaccharides
four+ sugar monomers formed by dehydration for carbohydrates
Important for energy storage, protection, structure building
Lipids
Any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents. They include many natural oils, waxes, and steroids.
- composed mainly of Hydrogen and Carbon Atoms
-non polar (hydrophobic)
- 40% of organic matter in living organisms / the human body
- important for energy storage and cell membrane formation
Fats
Composed of initial glycerol backbone bonded together to more fatty acids.
- properties of fats depend on the fatty acids that compose it
Monoglycerides
They are made up of glycerol and one fatty acid chain
Triglyceride
Three fatty acid chains + glycerol + condensation (3H2O). Triglycerides convert temporarily into monoglycerides and diglycerides during digestion.
Diglyceride
Two fatty acid chains covalently bonded to a glycerol molecule
Saturated Fat
- Straight linear structure (tightly packed)
- Has no double bonds between the carbons
- All bonds are taken up by hydrogen atoms
- Solid at room temp (required energy (heat) to melt)
Unsaturated Fats
- 1 or more double bonds between carbon atoms resulting in less hydrogen (less stable) atoms being bonded and adds kinks to the fatty acid
- liquid at room temperature
Phospholipids
- Formed from a glycerol molecule, two fatty acid tails, and a phosphate head group
- Have two fatty acid tails (nonpolar / hydrophobic (doesn’t contain oxygen))
- Phosphate head (polar / hydrophilic (contains oxygen))
- Amphipathic
Amphipathic
When a molecule has both polar and nonpolar properties
- molecules with polar / ionized and non polar regions
Micelle
An arrangement of molecules in a colloidal solution. It satisfies the molecular preference of each region of the molecule making it stable.
Liposome
Two layers of phospholipids. Spherical vesicles made up of biodegradable natural or synthetic phospholipids
Nucleic Acids
Central dogma of molecular biology. Information storage device for an organism. Provides instructions that are encoded by the order of monomers that make up the nucleic acid molecule.
DNA –> RNA –> Protein
DNA
Deoxyribose sugar
Deoxyribonucleic acid
Nucleic Acid Polymer
Double helix (2 strands)
RNA
Ribose Sugar
Ribonucleic acid
Nucleic Acid Polymer
Nucleotides
Nucleic Acids monomer that are composed of a pentose sugar, phosphate group, and a nitrogenous base.
Nitrogenous Base
Adenine, Guanine, Cytosine, Thymine, Uracil
Purines
Adenine and Guanine
Pyrimidines
Cytosine, Thymine, and Uracil
Nitrogenous Bases Pairs
A+T, A+U, C+G
Peptide Bond
bond between adjacent amino acids monomers
Polypeptide
2+ poly peptide bonds in a chain
What are amino acids made of?
Amino group, carboxyl group, and side chains (polar or nonpolar, pos or neg) (R)
Primary Structure
Linear sequence of amino acids in a chain
- encoded directly by genes (DNA)
10^30 possible ways to combine the 20 amino acids
Secondary Structure
Regions of the amino acids that are stabilized by hydrogen bonds with the balance of the polypeptide
- Alpha helices (coils that form in the amino acid)
- Beta pleated sheets (strands of the polypeptide chain laying side by side)
Tertiary Structure
3D shape of a protein that is stabilized by interactions between side chains of the amino acid
- 1 polypeptide
Quaternary Structure
Two or more polypeptides interact to form a single functional protein
Denaturing
Unfolding / breaking of proteins that then modify the protein and its structure
What makes up majority of the body?
Water due to the high amount of hydrogen and oxygen present in the body
When is there a charge of 0?
When an atom has equal number of protons and electrons.
When is there a negative charge?
When you add an electron it becomes negatively charged (net charge -)
When is there a positive charge?
When you lose an electron it becomes positively charges (net charge +)
Molecular Formula
Contains chemical symbols of the elements in the molecule (ex: C6H12O6)
- subscripts indicate how many atoms there are
Octet Rule
Atoms want a full valence shell (2 / 8 / 18) so the atom can be more stable. Atoms do this by sharing or exchanging electrons through bonds
Delta -
Partial negative (polar)
Delta +
Partial positive (polar)
Single Bond
sharing of one pair of electrons (one line)
Double Bond
sharing of two pairs of electrons (two lines)
Hydrocarbons
An organic compound consisting of largely C-C and C-H bonds
- hydrophobic and poorly soluble
How do you know when something can dissolve in water / is hydrophilic
When it contains Nitrogen or Oxygen or C-O / C-N bonds which are both polar
Nucleic Acid Polymer
The bond between sugar of one nucleotide and phosphate group of another / the next nucleotide
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Composed of carbon, hydrogen, oxygen, and nitrogen, and small amounts of sulfur
- 50% of organic matter in our bodies
- key structural, catalytic, regulatory and transport molecules
Structural (protein)
Cellular level (actin and tubulin) systems level (bone and skin / collagen and keratin)
Catalytic (protein)
Enzymes (catalyze reactions)
Regulatory (proteins)
Enzymes like receptors, transcription, neurotransmitters, and hormones
Transport (proteins)
Carrier proteins, membrane channels, pumps, transporters
Proteins monomer
Amino acids
- 20 different
- joined together by dehydration reactions between carboxyl and amino groups (peptide bond)
Electrostatic interactions
Ionic and other polar interactions including hydrogen bonds that promotes stability of protein through hydrophobic effects, and disulfide bridges
Disulfide Bridge
Type of covalent bond between Sulfur (SH + SH –> S-S)
- in tertiary and quaternary structures
Cells
contain all the necessary ingredients for metabolism, replication, communication, and physical interaction
- membrane bound and contain semi-fluid jelly like substance, proteins, ribosomes, and genetic material
- generate and consume energy, reproduce, encode info, move, synthesize and traffic, cell signaling, and cell communication
Eukaryotes
Nucleated organisms
- genetic material is contained within a double-membrane-bound (nucleus)
- larger and more compartmentalized
- plant cells, fungi cells, animal cells
Prokaryotes
Anucleated organisms
- do not have a membrane bound nucleus, genetic material is concentrated in a region of the cytoplasm called the nucleoid
- bacteria cells, archaea cells
Membrane bound
All cells are bounded by a plasma membrane that serves as a selective barrier allowing the exchange of water and nutrients
Cell Walls (cell)
Some cells have cell walls which add protection, rigidity, and prevails excessive uptake of water
Cytosol (cell)
Jelly like substance / aqueous solution inside the cell that suspends cellular components (ribosomes, organelles, cytoskeleton etc)
-holds chemical reactions (synthesis of proteins aided by ribosomes)
Cytoplasm (cell)
Everything within the cell except the nucleus
Chromosomes
The discrete units that store generate information that produce all the proteins that a cell needs to survive
- only visible during cell division
- prokaryotes usually only have a singe circular chromosome floating in a region of the cytosol called the nucleoid
-Eukaryotes have diverse chromosomal arrangements contained within a double-membrane lined nucleus
Nucleus (cell)
Contains almost all of the genes found in a eukaryote cell (some can be in other organelles)
Chromatin
Condensed DNA
Nucleolus (cell)
Responsible for ribosome production. Contains DNA that directs protein synthesis and make mRNA from DNA and transports it to the cytoplasm
- two bilayers that enclose the nucleus that is continuous with the endoplasmic reticulum
Ribosomes (cell)
Small structures composed of RNA and protein that carry out all the protein synthesis that occurs in the cell
- protein factors of the cell
Free ribosomes (cell)
Ribosomes that float in the cytosol and produce proteins that usually stay in the cytosol
Bound ribosomes (cell)
Ribosomes attached to the wall of the endoplasmic reticulum and produce proteins that may have more complex fates like excretion from the cell
Semi-autonomous Organelles
Organelles with their own DNA, can perform energy conversion
- Chloroplasts and Mitochondria
Endosymbiotic Theory
Eukaryotic cells evolved from simpler prokaryotic cells that merged together
- these organelles contain their own DNA, have a double membrane, and can grow and replicate independently of the cell
Mitochondria (cell)
Used to efficiently break down sugars to produce cellular energy without producing as many toxic waste products
- has two membranes
- inner membrane space: important for metabolic processes
- mitochondrial matrix: contains ribosomes and mitochondrial DNA
Chloroplasts
Convert energy in sunlight into bonds of sugar (photosynthesis)
- found only in plant cells, algae, and amoebas
- semi-autonomas organelle
Cytoskeleton
Network of fibers, which is comprised of microtubules, microfilaments, and intermediate filaments
- organized at an organelle called the centrosome
-important for movement in and out of the cell
Flagella
Extensions of plasma membrane that help with mobility
Cilia
Smaller extensions of plasma membrane that help with mobility
Tight Junctions (cell adhesion)
Small proteins that bind together the cell membranes of adjacent cells (watertight)
Desmosomes (cell adhesion)
A specific protein that lends strength to the adhesion of cells and often used to bind cells together
Gap Junctions (cell adhesion)
Channel proteins that directly connect the cytoplasm of two adjacent cells
Hydrophobic Effects
Amino acids will fold up to be away from water that gives it its 3D shape
Selective permiability
Cells only allow some solutes to cross
- cells detect signals from their environment
Nuclear Pore (cell)
Provide passage ways in/out of the nucleus
Endomembrane System
Parts of the cell which includes: Vesicles, ER, Golgi Apparatus, Lysosomes, Vacuoules
Vesicles (cell)
Tiny membrane - bound compartments that transport materials in / out the cell
Endoplasmic Reticulum (cell)
Network of stacked, flattened, phospholipid membranes
Rough ER (cell)
Membrane with ribosomes / protein synthesis and sorting
Smooth ER (cell)
Lacks ribosomes / diverse functions, metabolism, calcium storage, lipid synthesis, modification
Golgi Apparatus (cell)
Stack of flattened membrane bound compartments found further away from the nucleus
- secretion of substances out of the cell
- processing of proteins and lipids
- protein sorting and secretion
Lysosomes (cell)
Vesicles that contain acid hydrolases that centralize hydrolysis reaction of proteins, carbohydrates, nucleic acids, and lipids
- breaking things apart / down (polymers and monomers) to reuse it
Vacuoles (cell)
Filled with water and sometimes store additional molecules, including enzymes in solution
Motor proteins
Use chemical energy (from ATP) as a source of energy for movement
- carries cargo along the filament
- motor proteins stay in place and flagella moves
- exert force
The Extracellular Matrix
Cells secrete material that forms a gel-like meshwork outside of the cells’ membrane (in animals)
- strength (skin, cartilage, and organ coverings)
- Structural support (bone)
- organization (keeps cells together)
- cell signaling (helps sense environment outside the cell)
Osmoregulation
Controlling water balance to equalize the concentration of dissolved solids on either side of the membrane
Contractile Vacuole
Special type of vacuole that regulate the quantity of water inside a cell
- collects excess water in this organelle and then expels the water by contracting the walks of the contractile vacuole
Hydrogenosome
Found in eukaryotes that live in low oxygen environments
Ex: trichomeneas vaginalis, nyctotheus ovalis, loricfera
Cnidocyst
Contains one giant secretary organelle that can explosively eject a barn into organisms that activate the mechanism
- capture prey by impaling then on the ends of the barb as a defense against predators
