Study Guide Chapters 1-5 BIO101
Octect rule
Ch.02 states that the outermost shell of an element with a low atomic number can hold eight electrons (up to calcium, with an atomic number of 20). To achieve greater stability, atoms will tend to completely fill their outer shells and will bond with other elements to accomplish this goal by sharing electrons, accepting electrons from another atom, or donating electrons to another atom.
Intercellular junctions
Ch.03 A cell junction (or intercellular bridge[1]) is a type of structure that exists within the tissue of some multicellular organisms, such as animals. Cell junctions consist of multiprotein complexes that provide contact between neighboring cells or between a cell and the extracellular matrix. They also build up the paracellular barrier of epithelia and control the paracellular transport. Cell junctions are especially abundant in epithelial tissues. Cell junctions are especially important in enabling communication between neighboring cells via specialized proteins called communicating junctions. Cell junctions are also important in reducing stress placed upon cells.
Endocytosis
Ch.03 A type of active transport that moves particles, such as large molecules, parts of cells, and even whole cells, into a cell. Different variations of endocytosis, but all share a common characteristic: The plasma membrane of the cell invaginate, forming a pocket around the target particle. The pocket pinches off, resulting in the particle being contained in a newly created vacuole that is formed from the plasma membrane.
Active transport
Ch.03 Active transport- the method of transporting material that requires energy. Some active transport mechanisms move small molecular weight material. such as ions, through the membrane. ATP
Cell membrane (semi-permeable, selective)
Ch.03 Cell membrane is involved in secretion and excretion. The cell membrane contains channels and pumps that help move materials from one side of the cell to the other. These channels and pumps are made of proteins. Function of the cell membrane is to regulate which materials enter and leave the cell. A cell's plasma membrane defines the boundary of the cell and determines the nature of its contact with the environment. * the plasma membrane os composed mainly of a lipid bilayer *Selectively permeable- a property of cell membranes that allows some substances to pass through, while others can't. ** Semipermeable
Endergonic reactions
Ch.04 products have more free energy than the reactants. Products of these reactions can be thought of as energy-storing molecules. They are non-spontaneous. Will not take place on its own without the addition of free energy.
Glycolysis
Ch.04 the first step in the breakdown of glucose to extract energy for cell metabolism. Many living organisms carry out glycolysis as part of their metabolism. Glycolysis takes place in the cytoplasm of most prokaryotic and all eukaryotic cells.
Equation for respiration (what is produced)?
Ch.04 C₆H₁₂O₆ + O₂ → CO₂ + H₂O + energy glucose + oxygen → carbon dioxide + water + energy The equation is formulated by combining the three following processes into one equation: 1. Glycolysis — the breakdown of the form of a glucose molecule into two three-carbon molecules 2.The Tricarboxylic Acid Cycle or Krebs Cycle — the three-carbon pieces are pulled apart particle by particle to release the energy stored in those covalent bonds. This is where the CO₂ is procreated so to speak. 3. The Electron Transport Chain and Oxidative Phosphorylation — this sequence requires the oxygen and produces most of the energy. **produce large amounts of energy, to drive the bulk production of ATP. Breakdown of organic compounds to produce ATP
Relationship between photosynthesis and respiration
Ch.05 In Photosynthesis, plants use the sun's energy as light to transform carbon dioxide and water into glucose. In cellular respiration, glucose is ultimately broken down to yield carbon dioxide and water, and the energy from this process is stored as ATP molecules.
What results in anaerobic respiration? (products made)
Ch.05 Much less energy is released during anaerobic respiration than during aerobic respiration. This is because the breakdown of glucose is incomplete. Anaerobic respiration produces an oxygen debt. This is the amount of oxygen needed to oxidise lactic acid to carbon dioxide and water.Produce ethanol or lactic acid
Where does oxidative phosphorylation take place?
Ch.05 Oxidative phosphorylation takes place in the inner mitochondrial membrane, in contrast with most of the reactions of the citric acid cycle and fatty acid oxidation, which take place in the matrix.
Equation for photosynthesis (What is produced)?
Ch.05 Photosynthesis can be represented using a chemical equation. The overall balanced equation is... 6CO2 + 6H2O ------> C6H12O6 + 6O2 Sunlight energy Where: CO2 = carbon dioxide H2O = water Light energy is required C6H12O6 = glucose O2 = oxygen Plants use a process called photosynthesis to make food. During photosynthesis, plants trap light energy with their leaves. Plants use the energy of the sun to change water and carbon dioxide into a sugar called glucose.
Chlorophyll - pigment purpose in light reaction
Ch.05 Photosystem I and II and the Light Reaction ... The purpose of these photo systems is to collect energy over a "broad" range of ... When this happens, an e- in the other pigment is excited and the same things has to happen. Eventually ... Photo I consists largely of chlorophyll a molecules and contains no or few chlorophyll b.
Metabolism
All the chemical reactions that take place inside cells. including those that use energy and those that release energy. Ch.01
tRNA
Ch.02 Transfer ribonucleic acid (tRNA) is a type of RNA molecule that helps decode a messenger RNA (mRNA) sequence into a protein. tRNAs function at specific sites in the ribosome during translation, which is a process that synthesizes a protein from an mRNA molecule.
Lipids
Ch.02 diverse of compounds that are united by a common feature. are hydrophobic ("water-fearing"), or insoluble in H2O, because they are nonpolar molecules. ** they are hydrocarbons that include only nonpolar carbon-carbon or carbon-hydrogen bonds. Cells store energy for long-term use in the form of lipids called fats. Also provide insulation from the environment for plants and animals
Elements
Ch.02 Substances that cannot be broken down or transformed chemically into other substances. Each element is made of atoms, each with a constant number of protons and unique properties. 118 elements, only 92 occur naturally, fewer than 30 found in living cells. Remaining 26 are unstable, do no exist for very long. Each element is designated by its chemical symbol.
Scientific method ( hypothesis, theory, law)- control group, experimental group
Ch.01 - Scientific method- method of research w/ defined steps that include experiments & careful observation. * most important aspect is testing of the hypothesis -Hypothesis- a suggested explanation for an event, which can be tested. Day-to-day material that scientists work with and they are developed w/in the context of theories. -Scientific theory- Hypotheses, or tentative explanations, are generally produced w/in a context of a scientific theory. Is a generally accepted, thoroughly tested and confirmed explanation for a set of observations or phenomena - Scientific Law- often expressed in mathematical formulas, which describe how elements of nature will behave under certain specific conditions. Laws are concise descriptions of parts of the world that are amenable to formulaic or mathematical description - Control group- a part of the experiment that does not change. -Experimental group (variable)- is any part of the experiment that can vary or change during the experiment.
Organizational complexity (atoms---multicellular orgnsm)
Ch.01 1.Atom- smallest most fundamental unit of matter 2. Molecule- atoms form molecules -> chemical structure of at least two atoms held together by a chemical bond 3. Organelle -> structures that perform functions w/in a cell 4. Cells -> ex: human blood cells 5. Tissue -> ex: human skin tissue 6. Organs and organ systems -> ex: stomach and intestines 7. Organisms, populations & communities -> ex: in a park, each person is an organism. Together, all the people make up a population. All the plant & animal species in the park comprise a community 8. Ecosystem -> ex: ecosystem in park, living orgnsms & the environment in which they live 9. Biosphere -> encompasses all the ecosystems on earth
Molecules
Ch.01 A chemical structure consisting of at least two atoms held together by a chemical bond.
Atomic number
Ch.02 The atomic number of an element is equal to the number of protons that element contains. It is possible to determine the number of neutrons by subtracting the atomic number from the mass number. -these numbers provide information about the elements and how they will react when combined. Different boiling points, in different states (liquid, solid, or gas) at room temperature.
Atomic mass
Ch.02 The mass number is the number of protons plus the number of neutrons of that element. *It is possible to determine the number of neutrons by subtracting the atomic number from the mass number.
Characteristics of life
Ch.01 all groups of living organisms share key characteristics/functions -order -sensitivity or response to stimuli - plants bend toward a source of light or respond to touch movement towards a stimulus = positive response, movement away= negative -reproduction single-celled organisms 1st. duplicate DNA, then divide ='y as cells prepare to divide to form 2 cells multicellular-celled make spec.d rprdctve cells = 2 new indvdls. -adaptation all living orgms exibt "fit" to environment b/c evolution by natural selection -growth and development orgms g/d accrdng to instructions by their genes -regulation multiple regulatory mechanisms coordinate internal functions, such as transport of nutrients, response to stimuli, and coping with environment stresses. Ex: organ systems such as the digestive or circulatory systems perform specific functions like carrying oxygen throughout the body, removing wastes, delivering nutrients to every cell and coding the body. -Homeostasis The ability of an organism to maintain constant internal conditions "Steady state". -For ex: many organisms regulate their body temperature in a process known as thermoregulation. -Energy processing use source of energy for their metabolic activities. some orgnsms capture energy from the sun & convert to chemical energy in food; others use chemical energy from molecules they take in.
Adaptation, irritability (response to stimuli)
Ch.01movement toward stimulus = a positive response movement away stimulus = a negative response
mRNA VS tRNA
Ch.02
Subatomic particles ( protons, neutrons, electrons)
Ch.02 -Proton(P)- positively charged particle that resides in the nucleus of an atom and has a mass of 1 and a charge of +1. -Electron(E)- negatively charged particle that travels in the space around the nucleus. (outside the nucleus) has a negligible mass and charge of -1. -Neutrons(N)- like protons, reside in the nucleus of an atom. Have a mass of 1 w/ no charge. *the positive (P) and negative (E) charges balance each other in a neutral atom, has net zero charge. ** because (P) and (N) each have a mass of 1, the mass of an atom is equal to the number of (P) and (N) of that atom. The number of (E) does not factor into the overall mass, because the mass is so small.
Peptide bond
Ch.02 A peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O). This is a dehydration synthesis reaction (also known as a condensation reaction), and usually occurs between amino acids.
Compounds
Ch.02 All compounds are molecules, but not all molecules are compounds. Hydrogen gas (H2) is a molecule, but not a compound because it is made of only one element. Water (H2O) can be called a molecule or a compound because it is made of hydrogen (H) and oxygen (O) atoms.
Amino acids (20) - basic structure ( amino group, carboxyl group, and R group)
Ch.02 Amino acids are monomers that make up proteins. each amino acid has the same fundamental structure, which consists of a central carbon atom bonded to an amino group ( -NH2), a carboxyl group (-COOH), and a hydrogen atom. every amino acids also has another variable atom or group of atoms bonded to the central carbon atom known as the R group. The R group is the only difference in structure between the 20 amino acids; other wise acids are identical. The chemical nature of the R group determines the chemical nature of the amino acid within its protein. (whether it is acidic, basic, polar, or nonpolar)
Functional groups
Ch.02 An atom or group of atoms that replaces hydrogen in an organic compound. Functional groups define the structure of a family of compounds and determine its properties. The carboxyl and hydroxyl groups are functional groups that define the compounds they are part of as organic acids and alcohols, respectively.
Carbohydrates
Ch.02 Are macromolecules w/ which most consumers are somewhat familiar. * essential part of our diet. provide energy the body particularly through glucose, a simple sugar represented by (CH2O)n. n is the number of carbon atoms in the molecule ratio of carbon to hydrogen to oxygen is 1:2:1 in carb molecules. Carbs are classified into three subtypes: monosaccharides, disaccharides, and polysaccharides
Carbohydrates (4 major classes of biological macromolecules)
Ch.02 Carbohydrates store energy and provide building materials. Organic carbohydrates contain carbon. The framework of biological molecules consist predominantly of carbon atoms bonded to other carbon atoms or to atoms of oxygen, nitrogen, sulfur, or hydrogen. Carbon atoms possess for valence electrons and so can form four covalent bonds, molecules containing carbon can form straight chains, branches, or even rings. Covalent bonds between carbon and hydrogen are hydrocarbons. Covalent bonds between carbon and hydrogen are energy-rich. Because carbon-hydrogen covalent bonds store considerable energy, hydrocarbons make good fuels.
Key functional groups ( OH, PO4, COOH, NH2)
Ch.02 Carbon and hydrogen atoms both have very similar electronegativities, so electrons in C—C and C—H bonds are evenly distributed, and there are no in charge over the molecular surface. For this reason, hydrocarbons are nonpolar. Most organic molecules that are Produced by cells, however, also contain other atoms. Because these other atoms often have different electronegativities, molecules containing them exhibit regions of positive or negative charge, and so are polar. These molecules can be thought of as a C—H core to which specific groups of atoms called functional groups are attached. For example, a hydrogen atom bonded to an oxygen atom (—OH) is a functional group called a hydroxyl group. Functional groups have definite chemical properties that they retain no matter where they occur. The hydroxyl group, for example, is polar, because its oxygen atom, being very electronegative, draws electrons toward itself. Most chemical reactions that occur within organisms involve the transfer of a functional group as an intact unit from one molecule to another. Functional groups have definite chemical properties that they retain no matter where they occur.
3 Types of bonding ( covalent, ionic, hydrogen)
Ch.02 Covalent bond- a type of strong bond between two or more of the same or different elements; forms when electrons are shared between elements Ionic bond- a chemical bond that forms between ions of opposite charges Hydrogen bonds- a weak bond between partially positively charged hydrogen atoms and partially negatively charged elements or molecules
Nucleotide
Ch.02 DNA and RNA are made up of monomers known as nucleotides. The nucleotides combine with each other to form a polynucleotide, DNA or RNA. Each nucleotide is made up of three components: a nitrogenous base, a pentose (five-carbon) sugar, and a phosphate group. Each nitrogenous base in a nucleotide is attached to a sugar molecule, which is attached to a phosphate group.
DNA
Ch.02 DNA has a double helix structure. It is composed of two strands, or polymers, of nucleotides. The strands are formed with bonds between phosphate and sugar groups of adjacent nucleotides. The strands are bonded to each other at their bases with hydrogen bonds, and the strands coil about each other along their length, hence "double helix" The alternating sugar and phosphate groups lie on the outside of each strand, forming the backbone of the DNA. The nitrogenous bases are stacked in the interior, like the steps of a staircase, and these bases pair; the pairs are bound to each other by hydrogen bonds. The bases pair in such a way that the distance between the backbones of the two strands is the same along the molecules.
Dehydration and Hydrolysis reactions
Ch.02 Dehydration synthesis: form a covalent bond between two subunit molecules, an -OH group is removed from one subunit and a hydrogen atom is removed from the other. because the removal of the -OH group and H during the synthesis of a new molecule in effect constitutes the removal of a macromolecule, one water molecule is removed. Hydrolysis Greek hydro "water" + lyse "break" a hydrogen atom is attached to one subunit and a hydroxyl group to the other, breaking a specific covalent bond in the macromolecule. Hydrolytic reactions release the energy that was stored in the bonds that were broken.
Chemical reactions ( reactants, product)
Ch.02 In a balanced chemical reaction all of the matter (i.e., atoms or molecules) that enter into a reaction must be accounted for in the products of a reaction.Chemical reactions are described by chemical equations. Example: The reaction between hydrogen and oxygen to form water is represented by the following equation. 2 H2 + O2-----> 2 H2O It is often useful to indicate whether the reactants or products are solids, liquids, or gases by writing an s, l, or g in parentheses after the symbol for the reactants or products
Nucleic acids (4 major classes of biological macromolecules)
Ch.02 Key macromolecules in the continuity of life. carry genetic blueprint and instructions for functioning. 2 Main types: DNA and RNA DNA- genetic material, never leave the cell nucleus RNA- mostly involved in protein synthesis. communicate with the rest of the cell. Both are made up of monomers (nucleotides. Each nucleotide is made up of 3 components: a nitrogenous base, a pentose (5-carbon) sugar, and a phosphate group.
Lipids (4 major classes of biological macromolecules)
Ch.02 Lipids make membranes and store energy. Lipids are a loosely defined group of molecules with one main characteristic: they are insoluble in water. Fats and oils. Lipids have a very high proportion of nonpolar carbon-hydrogen (C-----H) bonds, and so long-chain lipids cannot fold up like a protein. When places in water many lipid molecules will spontaneously cluster together and expose what polar groups they have to the surrounding water while sequestering the nonpolar parts of the molecules together within the cluster. Phospholipids form membranes Fats are another kind of lipid, do not have a polar end. Fats consist of glycerol molecule to which is attached three fatty acids, one to each carbon of the glycerol backbone. contains 3 fatty acids, a fat molecule is called triglyceride. Because of the lack of a polar end they are not soluble in water. Saturated, unsaturated fats and polyunsaturated
mRNA
Ch.02 Messenger RNA (mRNA) is a large family of RNA molecules that convey genetic information from DNA to the ribosome, where they specify the amino acid sequence of the protein products of gene expression.
Molecular formula
Ch.02 Molecular formula:The molecular formula of a compound may be the empirical formula, or it may be a multiple of the empirical formula. For example, the molecular formula of butene, C4H8, shows that each freely existing molecule of butene contains four atoms of carbon and eight atoms of hydrogen. Its empirical formula is CH2. Structural formula:
Primary, secondary, tertiary, structure of protein molecules
Ch.02 Primary- sequence of a chain of amino acids Secondary- hydrogen bonding of the peptide backbone causes the amino acids to fold into a repeating pattern Tertiary- Three- dimensional folding pattern of a protein due to side chain interactions
Structural (muscle) and functional (enzymes) proteins
Ch.02 Proteins may be structural, regulatory, contractile, or protective; they may serve in transport, storage, or membranes; or they may be toxins or enzymes. Each cell in a living system may contain thousands of different proteins, each with a unique function. their structures, like their functions, vary greatly. They are all, however, polymers of amino acids, arranged in a linear sequence. Functions of proteins are very diverse because there are 20 different chemically distinct amino acids that for long chains, and the amino acids can be in any order. proteins can function as enzymes or hormones. Enzymes are produced by living cells, are catalysts in biochemical reactions (like digestion) and are usually proteins. each enzyme is specific for the substrate (a reactant that binds to an enzyme) upon which it acts. Enzymes can function to break molecular bonds, to rearrange bonds, or to form new bonds. and ex: is salivary amylase, which breaks down amylose, a component of starch.
Proteins (4 major classes of biological macromolecules)
Ch.02 Proteins perform the chemistry of the cell. Enzyme catalysis facilitate specific chemical reactions. globular proteins with 3d shape fits snugly around the chemicals they work on. Defense- cell surface receptors form the core of the body's hormone and immune systems. Transport- transport specific molecules and irons.
RNA
Ch.02 RNA- ribonucleic acid mostly involved in protein synthesis. DNA uses an RNA intermediary to communicate with the rest of the cell.
Buffer concept
Ch.02 Readily absorb excess H+ or OH-, keeping the pH of the body carefully maintained in the aforementioned narrow range. Carbon dioxide is part of the prominent buffer system in the human body; Without this buffer system, the pH in our bodies would fluctuate too much and we would fail to survive.
Solutions (characteristics of solvent and solute)
Ch.02 Solvent- a substance capable of dissolving another substance. The charged particles will form hydrogen bonds with surrounding layer of water molecules. Referred to as a sphere of hydration and serves to keep the particles separated or dispersed in the water. A positively charged sodium ion is surrounded by the partially negative charges of oxygen atoms in water molecules. A negatively charged chloride ion is surrounded by the partially positive charges of hydrogen atoms in water molecules. The spheres of hydration are also referred to as hydration shells. The polarity of the water molecule makes it an effective solvent and is important in its many roles in living systems.
Polar molecule (water) acts like a universal solvent - charges at opposite side of water molecule
Ch.02 Water is capable of dissolving a variety of different substances, which is why it is such a good solvent. And, water is called the "universal solvent" because it dissolves more substances than any other liquid. This is important to every living thing on earth. It means that wherever water goes, either through the ground or through our bodies, it takes along valuable chemicals, minerals, and nutrients. It is water's chemical composition and physical attributes that make it such an excellent solvent. Water molecules have a polar arrangement of the oxygen and hydrogen atoms—one side (hydrogen) has a positive electrical charge and the other side (oxygen) had a negative charge. This allows the water molecule to become attracted to many other different types of molecules. Water can become so heavily attracted to a different molecule, like salt (NaCl), that it can disrupt the attractive forces that hold the sodium and chloride in the salt molecule together and, thus, dissolve it.
Characteristic of H2O ( cohesion, adhesion, heat of vaporization, etc.)
Ch.02 Water is polar Each H2O molecule attracts other H2O molecules because of the positive and negative charges in the different parts of the molecules. Water also attracts other polar molecules forming hydrogen bonds. Hydrophilic ("water-loving") Hydrophobic ("water-fearing") Water stabilizes temperature (kinetic energy) as motion increases, energy is higher and thus temperature is higher. Water is an excellent solvent - a substance capable of dissolving another substance Water is cohesive- H2O molecules are attracted to each other (because of hydrogen bonding), keeping the molecules together at the liquid-air (gas) interface, although there is no more room in the glass. Surface tension- the capacity of a substance to withstand rupture when placed under tension or stress. Adhesion- the attraction between water molecules and other molecules
Structural formula
Ch.02 a formula that shows the arrangement of atoms in the molecule of a compound.
Proteins
Ch.02 are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. -may be structural, regulatory, contractile, or protective; serve in transport, storage, or membranes; pr they may be toxins or enzymes -all are polymers of amino acids, arranged in a linear sequence -functions diverse, can function as enzymes or hormones -4 levels of protein structure: primary, secondary, tertiary, and quaternary
Nucleic Acids
Ch.02 key macromolecules in the continuity of life carry genetic blueprint of a cell and instructions and functioning two main types: DNA and RNA DNA- genetic material found in all living organisms RNA- mostly involved in protein synthesis DNA and RNA is made up of monomers known as nucleotides
Major biological elements
Ch.02 large molecules necessary for life are built from smaller organic molecules -> biological macromolecules. -4 classes: 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids all or organic, meaning they contain carbon, and may contain hydrogen, oxygen, nitrogen, phosphorus, sulfur, and additional minor elements.
Macromolecules (4 major of biological importance - proteins, lipids, carbohydrates, nucleic acids) - able to recognize structures
Ch.02 large molecules necessary for life that are built from smaller organic molecules. Four major classes; carbohydrates, lipids, proteins, and nucleic acids each is an important component of the cell and performs a wide array of functions. Combined, these molecules make up the majority of a cell's mass. Biological macromolecules are organic, meaning that they contain carbon. In many cases, these macromolecules are polymers, molecules built by linking together a large number of small, similar chemical subunits, like railroad cars coupled to form a train. Complex carbohydrates like starch are polymers of amino acids, and nucleic acids (DNA and RNA) are polymers of nucleotides.
Matter
Ch.02 life is made up of matter, most fundamental level. Matter occupies space and has mass. All matter is composed of elements.
pH concept, acid, base, neutral (understand role of H ion concentration and major subunits of proteins, lipids, carbohydrates, and nucleic acids)
Ch.02 pH concept: pH scale: A scale ranging from 0 to 14 that measures the approximate concentration of hydrogen ions of a substance.The pH of a solution is a measure of the molar concentration of hydrogen ions in the solution and as such is a measure of the acidity or basicity of the solution. The letters pH stand for "power of hydrogen" and numerical value for pH is just the negative of the power of 10 of the molar concentration of H+ ions. Acid: a substance that donates hydrogen ions and therefore lowers pH Base: a substance that absorbs hydrogen ions and therefore raises pH Neutral: pure water is neutral. has a pH of 7.0 anything below 7.0 (ranging from 0.0-6.9) is acidic, anything above 7.0 (7.1-14.0) is alkaline
Atoms
Ch.02 smallest component of an element that retains all of the chemical properties of that element. Cannot be broken down into anything smaller while still retaining its properties of that element. Atoms combine together to form molecules. All contain protons, electrons, and neutrons. Atoms are made up of protons and neutrons located within the nucleus, and electrons surrounding the nucleus.
Carbon
Ch.02 -life is "carbon-based" "foundation" element for molecules in living things bonding properties of carbon atoms that are responsible for its important role. Contains 4 electrons in its outer shell -> can form 4 covalent bonds with other atoms or molecules. * simplest organic carbon molecule is methane (CH4) = 4 hydrogen atoms bind to a carbon atom.
Ions
Ch.02 an atom or compound that does not contain equal numbers of protons and electrons, and therefore has a net charge. + ions are formed by losing electrons and are called cations. - ions are formed by gaining electrons and are called anions. EX: sodium only has one electron in its outermost shell. It takes less energy for sodium to donate that one electron than it does to accept seven more electrons to fill the outer shell. If sodium loses an electron, it now has 11 protons and only 10 electrons, leaving it with an overall charge of +1. Now called sodium ion.
Phospholipids
Ch.02 are the major constituent of the plasma membrane. like fats, they are composed of fatty acid chains attached to a glycerol or similar backbone.
Hypertonic
Ch.03 hyper refers to the extracellular fluid having a higher concentration of solutes that the cell's cytoplasm. The fluid contains less water than the cell does. Cell has a lower concentration of solutes, the water will leave the cell. in effect, the solute is drawing the water out of the cell. This may cause and animal cell to shrivel or crenate.
Cytoskeleton (microfilaments etc. - different types)
Ch.03 Cytoskeleton- the network of protein fibers that collectively maintains the shape of the cell, secures some organelles suspended in the gel-like cytosol, the cytoskeleton, and various chemicals. 3 types of fibers w/in the cytoskeleton: microfilaments, aka actin filaments, intermediate filaments, and microtubules Microfilaments are the thinest of the cytoskeletal fibers and function in moving cellular components. EX: during cell division. muscle cells, responsible for muscle contractions. Intermediate filaments are of intermediate diameter and have structural functions, such as maintaining the shape of the cell and anchoring organelles. ex: keratin Microtubules are the thickest fibers. Hollow tubes that can dissolve and reform quickly. Guide organelle movement and are the structures that pull chromosomes to their poles during cell division. Also the structural components of flagella and cilia. Are organized as a circle of nine double microtubules on the outside and two microtubules in the center. ** Cytoskeleton is a network of protein strands in the cytosol; the 3 major components are: microfilaments, microtubules, intermediate filaments.
Diffusion
Ch.03 Diffusion- a passive process of transport of low-molecular weight material down its concentration gradient. Materials move w/in the cell's cytosol by diffusion, and certain materials move through the plasma membrane by diffusion. Expends no energy. The greater the difference in concentration, the more rapid the diffusion. The closer the distribution og the material gets to equilibrium, the slower the rate of diffusion becomes. More massive molecules move more slowly, they diffuse more slowly. Higher temperatures increase the energy and therefore the movement of molecules, increasing the rate of diffusion. As density of the solvent increases, the rate of diffusion decreases. the molecules slow down because they have a more difficult time getting through the denser medium. * Diffusion is the movement of molecules from high to low concentration
Hypotonic
Ch.03 In a hypotonic solution, such as tap water, the extracellular fluid has a lower concentration of solutes than the fluid inside the cell, and water enters the cell. Hypo- means that the extracellular fluid has a lower concentration of solutes, or a lower osmolarity, than the cell cytoplasm. Also means that the extracellular fluid has a higher concentration of water than does the cell. Water will follow its concentration gradient and enter the cell. this may cause an animal cell to burst, or lyse.
Isotonic (solution)
Ch.03 In an isotonic solution, the extracellular fluid has the same osmolarity as the cell. If the concentration of solutes of the sell matched that of the extracellular fluid, there will be no net movement of water into or out of the cell. An isotonic solution refers to two solutions having the same osmotic pressure across a semipermeable membrane. This state allows for the free movement of water across the membrane without changing the concentration of solutes on either side.
Importance of tools in biology (microscope)
Ch.03 Microscope: is an instrument that magnifies an object. Most images of cells are taken with a microscope and are called micrographs. Microscopes were used in the 17th century to study cells. Light microscope uses optical lenses to magnify objects by bending light rays. The power of the microscope to show detail more clearly is called the resolution Dissecting microscope: have lower magnification (20 to 80 times the object size) than light microscopes and can provide 3D view. designed to give a magnified and clear view of tissue structure as well as the anatomy of the whole organism. The advantage of van Leeuwenhoek's microscopes was that the lenses were ground very precisely
Organelle (nucleus, mitochondria, chloroplasts, Golgi apparatus, rough endoplasmic reticulum, smooth endoplasmic reticulum, centrosome)
Ch.03 Organelle- a membrane bound compartment or sac within a cell. "little organ" Organelles that are surrounded by two membranes and contain DNA sre the nucleus and mitochondria.
Osmosis
Ch.03 Osmosis- is the diffusion of water through a semipermeable according to the concentration gradient of water across the membrane. Osmosis transports only water across a membrane and the membrane limits the diffusion of solutes in the water. Special case of diffusion. Water always moves from an area of higher concentration (of water) to one of lower concentration (of water). The solute cannot pass through the selectively permeable membrane.
Passive transport
Ch.03 Passive transport- a method of transporting materials that does not require energy. Naturally occurring, substances move from an area of higher concentration to an area of lower concentration in diffusion. The most direct forms of membrane transport are passive.
Membrane proteins (recognition, receptor, transport, and structure proteins)
Ch.03 Peripheral membrane proteins, or extrinsic proteins, do not interact with the hydrophobic core of the phospholipid bilayer. Instead they are usually bound to the membrane indirectly by interactions with integral membrane proteins or directly by interactions with lipid polar head groups.
Characteristics of phospholipids
Ch.03 Phospholipids make up the cell membrane Phospholipids consist of a glycerol molecule, two fatty acids, and a phosphate group that is modified by an alcohol. The phosphate group is the negatively-charged polar head, which is hydrophilic. The fatty acid chains are the uncharged, nonpolar tails, which are hydrophobic. Since the tails are hydrophobic, they face the inside, away from the water and meet in the inner region of the membrane. Since the heads are hydrophilic, they face outward and are attracted to the intracellular and extracellular fluid. If phospholipids are placed in water, they form into micelles, which are lipid molecules that arrange themselves in a spherical form in aqueous solutions.
Major difference between plant and animal cells
Ch.03 Plant cell contains a cell wall, chloroplasts, and a central vacuole.
Functions of cytoskeleton
Ch.03 Maintains cell shape, secures organelles in specific positions, allows cytoplasm and vesicles to move w/in the cell, and enables unicellular organisms to move independently.
Hooke
Ch.03 1st book published Micrographia devised compound microscope w/ an illumination system; observed sponges, formainfera, insects and bryozoans discovered plant cells, images of thin slices of cork came up "cell"
Metabolism
Ch.04 metabolism- all the chemical reactions that take place inside cells, including those that use energy and those that release energy.
Major parts of a cell structure and functions
Ch.03 Plasma Membrane: seperates cell from external environment: controls passage of organic molecules, ions, water, oxygen, and wastes into and out of the cell. Present in Prokaryotes: yes Present in animal cells: yes Present in plant cells: yes Cytoplasm: Provides structure to cell; site of many metabolic reactions: medium in which organelles are found Present in Prokaryotes: yes Present in animal cells: yes Present in plant cells: yes Nucleoid: Location of DNA Present in Prokaryotes: Yes Present in animal cells: No Present in plant cells: No Nucleus: Cell organelles that houses DNA and directs synthesis of ribosomes and proteins Present in Prokaryotes: No Present in animal cells: Yes Present in plant cells: Yes Ribosomes: Protein synthesis Present in Prokaryotes: yes Present in animal cells: yes Present in plant cells: yes Mitochondria: ATP production/ cellular respiration Present in Prokaryotes: no Present in animal cells: yes Present in plant cells: yes Peroxisomes: Oxidizes and breaks down fatty acids and amino acids, and detoxifies poisons Present in Prokaryotes: no Present in animal cells: yes Present in plant cells: yes Vesicles and vacuoles: Storage and transport; digestive function in plant cells Present in Prokaryotes: no Present in animal cells: yes Present in plant cells: yes Centrosomes: unspecified role in cell division in animal cells; organizing center of microtubules in animal cells Present in Prokaryotes: no Present in animal cells: yes Present in plant cells: no Lysosomes: digestion of macromolecules; recycling of worn-out organelles Present in Prokaryotes: no Present in animal cells: yes Present in plant cells: no Cell wall: Protection, structural support and maintenance of cell shape Present in Prokaryotes: yes, primarily in bacteria but not in archaea Present in animal cells: no Present in plant cells: yes, primarily cellulose Chloroplasts: photosynthesis Present in Prokaryotes: no Present in animal cells: no Present in plant cells: yes Endoplasmic reticulum: modifies proteins and synthesizes lipids Present in Prokaryotes: no Present in animal cells: yes Present in plant cells: yes Golgi apparatus: Modifies, sorts tags, packages, and distributes lipids and proteins Present in Prokaryotes: no Present in animal cells: yes Present in plant cells: yes Cytoskeleton: Maintains cell's shape, secures organelles in specific positions, allows cytoplasm and vesicles to move w/in the cell, and enables unicellular organisms to move independently. Present in Prokaryotes: yes Present in animal cells: yes Present in plant cells: yes Flagella: cellular iocomotion Present in Prokaryotes: some Present in animal cells: some Present in plant cells: no, except for some plant sperm Cilia: Cellular iocomotion, movement of particles along extracellular surface of plasma membrane, and filtration Present in Prokaryotes: no Present in animal cells: some Present in plant cells: no
Ribosomes
Ch.03 Ribosome- a cellular structure that carries out protein synthesis. When viewed electron microscope, appear as clusters or single tiny dots floating freely in the cytoplasm. May be attached to either the cytoplasmic side of the plasma membrane or the cytoplasmic side of the endoplasmic reticulum. Consist of large and small subunits. Are enzyme complexes that are responsible for protein synthesis. Found in practically every cell, smaller in prokaryotic cells. abundant in immature red blood cells for the synthesis of hemoglobin, functions in the transport of oxygen throughout the body. Made of protein and RNA
Spontaneous generation
Ch.03 Spontaneous generation or anomalous generation is an obsolete body of thought on the ordinary formation of living organisms without descent from similar organisms. Typically, the idea was that certain forms such as fleas could arise from inanimate matter such as dust, or that maggots could arise from dead flesh.
Lipid bilayer (phospholipids)
Ch.03 The main fabric of the membrane is composed of two layers of phospholipid molecules, and the polar ends of these molecules. Both surfaces of the plasma membrane are hydrophilic. Lipid bilayer is a universal component of all cell membranes. The structure is called a "lipid bilayer" because it composed of two layers of fatty acids organized in two sheets. The lipid bilayer is typically about five nanometers to ten nanometers thick and surrounds all cells providing the cell membrane structure.
Exocytosis
Ch.03 The opposite of phagocytosis in that its purpose is to expel material from the cell into the extracellular fluid. A particle enveloped in a membrane fuses with the interior of the plasma membrane. This fusion opens the membranous envelope to the exterior of the cell, and the particle is expelled into the extracellular space. In exocytosis, a vesicle migrates to the plasma membrane, binds and releases its contents to the outside of the cell.
Phagocytosis
Ch.03 The process by which large particles, such as cells, are taken in by a cell. ex: when microorganisms invade the human body, a type of white blood cell called neutrophil removes the invader through this process surrounding and engulfing the microorganisms, which is then destroyed by the neutrophil.
Sodium potassium pump- importance
Ch.03 The process of moving sodium and potassium ions across the cell membranes is an active transport process involving the hydrolysis of ATP to provide the necessary energy. It involves an enzyme referred to as Na+/K+-ATPase. This process is responsible for maintaining the large excess of Na+ outside the cell and the large excess of K+ ions on the inside. A cycle of the transport process is sketched below. It accomplishes the transport of three Na+ to the outside of the cell and the transport of two K+ ions to the inside. This unbalanced charge transfer contributes to the separation of charge across the membrane. The sodium-potassium pump is an important contributor to action potential produced by nerve cells. This pump is called a P-type ion pump because the ATP interactions phosphorylates the transport protein and causes a change in its conformation.
How do cells react to various tonicity (isotonic, hypotonic, hypertonic)
Ch.03 Tonicity describes the amount of solute in a solution. The measure of tonicity of a solution, or the total amount of solutes dissolved in a specific amount of solution is the osmolarity. Hypertonic- In animal cells, being in a hypertonic environment results in crenation, where the shape of the cell becomes distorted and wrinkled as water leaves the cell. Some organisms have evolved methods of venting Hypertonicity; for example, saltwater is hypertonic to the fish that live in it. Since they cannot isolate themselves from osmotic water loss, because they need a large surface area in their gills for gas exchange, they respond by drinking large amounts of water, and excreting the salt. This process is called osmoregulation. An example of an animal cell showing the affects of hypertonicity is when your fingers wrinkle. Hypotonic- When plants are placed in water, the water enters their cells (this is because their sap has a strong solution). The water enters the plant through osmosis and fills up the cell with water to its maximum capacity. A strong cell wall stops the cells from bursting (as in animal cells) and makes the plant to become turgid (becomes rigid/stiff because of water.) Isotonic- ."ISO" means the same meaning that the osmotic pressure and concentration of solutes is the same in both the internal and external environments of the cell. Cells isotonic to their surrounding solutions have an equal concentration of solutes in and out of the cell membrane. This creates a dynamic equilibrium that maintains the status of the cell. No change will occur in the cell.
Cell theory
Ch.03 Unified cell theory: state that all living things are composed of one or more cells, that the cell is the basic unit of life, and that all new cells arise from existing cells. It took 150 years for the cell theory to be developed after microscopes were invented because microscope technology had to improve before cell parts could be observed One early piece of evidence supporting the cell theory was the observation that cells come from other cells. 3 parts of the cell theory 1. Living things are composed of cells 2. Cells are the basic unit of structure and function 3. Cells arise only from other cells. Major events in the history of cell biology: 1. Cloning animals 2. Growing bone tissue for transplant 3. Discovery of cell parts
Vesicle
Ch.03 Vesicle- a small, membrane-bound sac that functions in cellular storage and transport; its membrane is capable of fusing w/ the plasma membrane and the membranes of the endoplasmic reticulum and Golgi apparatus.
Entropy - relationship to order
Ch.04 "The entropy of an isolated system never decreases, because isolated systems spontaneously evolve towards thermodynamic equilibrium, which is the state of maximum entropy." Therefore, entropy will only increase with time in an isolated system if it has not reached thermodynamic equilibrium. The universe is an isolated system that had a very low entropy state in the past, i.e. at or shortly after the big bang. Therefore it is in the process of approaching thermodynamic equilibrium. Therefore it is a circumstance of the state of our universe that causes entropy to increase with time, at this time. It is not a law. Conservation of energy and information are laws. Increasing entropy is a circumstance. That is why they are different.
Electron carriers ( NAD, FAD)
Ch.04 A number of molecules can act as electron carriers in biological systems. In cellular respiration, there are two important electron carriers, nicotinamide adenine dinucleotide (abbreviated as NAD+ in its oxidized form) and flavin adenine dinucleotide (abbreviated as FAD in its oxidized form). The NAD+ molecule is used to accept electrons (becomes reduced) in several chemical reactions in glycolysis and the Krebs cycle. NAD+ accepts a hydrogen ion (H+) and two electrons (2e−), as it becomes reduced to NADH + H+. The NADH moves to the electron transport chain and donates a pair of electrons (becomes oxidized) to the first compound in the chain. The oxidation of NADH to NAD+ results in the liberation of 53 kcal/mole (under standard conditions).
ETC - electron transport chain - what is result? what happens to oxygen?
Ch.04 A series of 4 large, multi-protein complexes embedded in the inner mitochondrial membrane that accepts electrons from donor compounds and harvests energy from a series of chemical reactions to generate a hydrogen ion gradient across the membrane. Oxygen is the final electron acceptor and water is produced.
Enzymes - Characteristics
Ch.04 An enzyme is a protein molecule that is a biological catalyst with three characteristics. First, the basic function of an enzyme is to increase the rate of a reaction. Most cellular reactions occur about a million times faster than they would in the absence of an enzyme.
Energy
Ch.04 Definition (1) The capacity for work. (2) The ability to do work, or produce change. Supplement Energy exists in different forms but is neither created nor destroyed; it simply converts to another form. Examples of energy include: kinetic, potential, thermal, gravitational, elastic, electromagnetic, chemical, nuclear, and mass. Energy can be expressed in joules or ergs In biology, energy is often stored by cells in biomolecules, like carbohydrates (sugars) and lipids. The energy is released when these molecules have been oxidized during cellular respiration. The energy released from them when they are oxidized during cellular respiration is carried and transported by an energy-carrier molecule called ATP.
Exergonic reactions
Ch.04 Describes a chemical reaction that results in products with less chemical potential energy than the reactants, plus the release of free energy. "exiting the system" spontaneous reactions, and their products have stored energy than the reactants.
ATP- energy currency- how does it work?
Ch.04 Nearly every function in cells requires energy. ATP is the currency for this energy meaning that it is how energy is stored and released at the right time and in the right place. All energy producing or consuming cellular metabolism requires ATP as the energy source. There are some minor exceptions by which the cell can obtain a very small amount of energy but that is another topic.There are 3 forms of fuel that the body can use for energy production: carbohydrates (glucose), protein, and fat. Each of these 3 fuel forms go through different pathways to claim that energy and the yield of that energy is different for each form as well. Carbohydrates - Generally go through glycolysis to produce ATP. This can be accomplished in the absence of oxygen but with a relatively low yield in energy or ATP. Pyruvate is also produced and, in the absence or deficiency of oxygen, is converted to lactic acid (lactate). Proteins - are deaminated in the liver and they can then enter the Kreb's cycle at a couple of different spots and result in energy in this method. Because it must be deaminated (remove an ammonia group on a chemistry level) before this can occur, it takes more energy to break it down. This will also be the topic of a future discussion. ATP is produced as well as some intermediate products (NADH, FADH) that ultimately result in ATP after going through the Electron Transport System (ETS) Fats - stored, and often consumed, in the form of triglycerides. The fatty acids are removed and enter the mitochondria where they go through a process called 'Beta-Oxidation' where 2 carbon molecules are removed at a time. These 2 carbon molecules can then enter the Kreb's cycle and produce energy. Fats can store a tremendous amount of energy within them. However, Protein & Fat catabolism requires oxygen in order to yield the energy needed. Each of these methods of energy conversion will be discussed in further detail in the near future but I wanted to give a good overview of where the energy comes from with the different macronutrients & how that energy is utilized as ATP.
Second Law of thermodynamics
Ch.04 Second Law: all energy transfers and transformations are never completely efficient. In every energy transfer, some amount of energy is lost in a form that is unusable. It most cases, this form is heat energy. Heat energy is defined as the energy transferred from one system to another that is not work. Ex: when a light bulb is turned on, some of the energy being converted from electrical energy into light energy is lost as heat energy. ***The second law of thermodynamics states that the entropy of any isolated system not in thermal equilibrium almost always increases.
Electrons, covalent bonding, and energy (how related)
Ch.04 The electrons on the outermost energy level of the atom are called valence electrons. The valence electrons are involved in bonding one atom to another. The attraction of each atom's nucleus for the valence electrons of the other atom pulls the atoms together. As the attractions bring the atoms together, electrons from each atom are attracted to the nucleus of both atoms, which "share" the electrons. The sharing of electrons between atoms is called a covalent bond, which holds the atoms together as a molecule. A covalent bond happens if the attractions are strong enough in both atoms and if each atom has room for an electron in its outer energy level. Atoms will covalently bond until their outer energy level is full. Atoms covalently bonded as a molecule are more stable than they were as separate atoms.
First Law of thermodynamics
Ch.04 Thermodynamics- study of energy transfer involving physical matter. First Law: states that the total amount of energy in the universe is constant and conserved. "There has always been, and always will be" energy must be transferred from place to place or transformed into different forms, but it cannot be created or destroyed. Ex: gas stoves transform chemical energy from natural gas into heat energy. ****The first law, also known as Law of Conservation of Energy, states that energy cannot be created or destroyed in a chemical reaction.
Metabolic pathway
Ch.04 metabolic pathways are a series of reactions catalyzed by multiple enzymes. Feedback inhibition, where the end product of the pathway inhibits an upstream process, is an important regulatory mechanism in cells. he initial chemical (metabolite) is modified by a sequence of chemical reactions. These reactions are catalyzed by enzymes, where the product of one enzyme acts as the substrate for the next.
Energy (definition)
Power that may be translated into motion, overcoming resistance or causing physical change; the ability to work
Homeostatis
The ability of an organism to maintain constant internal conditions "Steady state". -For ex: many organisms regulate their body temperature in a process known as thermoregulation. Ch.01
Citric Acid (Krebs) cycle - production of electron carriers
The citric acid cycle - also known as the tricarboxylic acid (TCA) cycle or the Krebs cycle - is a series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetate derived from carbohydrates, fats and proteins into carbon dioxide and chemical energy in the form of adenosine triphosphate (ATP). In addition, the cycle provides precursors of certain amino acids as well as the reducing agent NADH that is used in numerous other biochemical reactions. Its central importance to many biochemical pathways suggests that it was one of the earliest established components of cellular metabolism and may have originated abiogenically. The ATP that is produced is generated via substrate-level ... and where electron carriers are reduced to form NADH and FADH2.
