Biology 1406 Exam #1 2023 with verified question and answers

Biology the scientific study of life Hypothesis a suggested explanation for an observation which can be tested Theory a tested observation with an explanation Levels of Organization Small --to-- Big Atom - molecule - macromolecules - organelles - cells, tissues - organs - organ system - organ system - organisms - populations - communities - ecosystems - biosphere Diversity of Life: The 3 Domains -Archaea -Bacteria -Eukarya atom smallest functional units of matter that form all chemical substances and thus organisms element substance that cannot be broken down to other substances by chemical reactions isotope atoms of the same element that have different numbers of neutrons or different atomic forms of the same element. molecule two or more atoms held together by covalent bonds ion an atom or group of atoms that has gained or lost one or more electrons, thus acquiring a charge cation positively charged ion mass number number of protons + neutrons atomic number number of protons number of neutrons = mass number - atomic number Describe the basic structure of the atom An atom is the smallest unit of matter that defines an element. This unit consists of a nucleus surrounded by orbiting, negatively charged electrons. The nucleus contains positively charged protons and, most often, neutral neutrons. The number of protons in the nucleus determines the number of electrons, maintaining electrical neutrality, and the fundamental nature of the atom. Also, as tiny as atoms are, they still consist mostly of empty space. ionic bond attractive force between oppositely charged ion, anion and cation covalent bond sharing of electrons - may be equal or unequal sharing polar covalent bond uneven sharing of pairs of electrons, determined by the electronegativity of atoms in the molecule, creates slight positive or negative charges in different regions of the molecule hydrogen bond attraction between opposite charges of atoms in different covalently bonded molecules atomic mass is measured in Daltons Unstable isotopes give off particles and energy in the form of radiation Top Four Elements Needed for Life -Oxygen -Nitrogen -Hydrogen -Carbon Matter Anything that has mass and takes up space (is made of elements) Protons (p⁺) -Located in nucleus -Effect Charge -Atomic # -Atomic Mass (p+n) Neutrons (n⁰) -Located in nucleus -Effect Charge -Effect the atomic Mass (p+n) -To find on period table, take atomic mass # - atomic # Electrons (e⁻) -Located outside nucleus, in orbitals (shells) -Effect Charge -Responsible for interactions between other atoms -To find on periodic table, in stable atoms they are the same as atomic # Valence Shell / Valance Electron The valence shell is the outermost shell. Electrons on the valence shell are considered to be valence electrons How to find protons, neutrons, and electrons by looking at periodic table p = atomic # n = mass # - atomic # e = atomic number Non-Polar Bond a covalent bond in which electrons are shared equally Non-Covalent Bonds Weaker and more transient than covalent bond. -Hydrogen Bonds -Ionic Bonds -Van Der Waals Interactions -Hydrophobic Forces Properties of Water -high heat capacity -high heat of vaporization -ability to dissolve in polar molecules -cohesion and adhesion -disassociation into ions to generate pH Chemical Reaction A process during which chemical bonds between atoms are broken and new ones are formed. Producing one or more different substances. Calorie amount of heat required to raise the temp of 1g of water by 1C Solution A mixture that forms when one substance dissolves another. Solvent A liquid substance capable of dissolving other substances (Water is an EXCELLENT solvent!) Organic Compound Complex molecules organized around skeletons of carbon atoms arranged in rings or chains. Isomers Compounds that have the same molecular formula but different structures. Functional Group A specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and usually involved in chemical reactions. Hydrophobic Having an aversion to water; tending to coalesce and form droplets in water. Hydrophilic Attracted to water Acids -increase ion concentration OH⁻ H⁺ pH 7 Bases -decrease ion concentration - OH⁻ H⁺ -pH 7 Buffers A substance that consists of acid and base forms in a solution and that minimizes changes in pH when extraneous acids or bases are added to the solution. -minimize changes in H⁺ and OH⁻ Saturated Tryglycerides -no double bonds between carbon -solid at room temp Unsaturated Tryglcerides(fatty acid) -at least 1 double bond -liquid at room temp How can water take in a lot of heat but the temp still remain the stable? Water can take in a lot of heat and retain a stable temperature through water's high heat capacity. What does pH test? pH tests how acidic or basic a solution is. Four main classes of large biological molecules? Carbohydrates Lipids Proteins Nucleic acids Polymers are made up of smaller molecules known as monomers How do you make polymers? Through dehydration reactions (monomers combine and in the process release a water molecule) How do you break polymers? Through hydrolysis (when you add a water molecule to a polymer they break back down into monomers) Carbohydrates -provide / store energy, provide structure, cell-cell recognition when present in proteins -there are 3 classes of carbohydrates: monosaccharides, disaccharides, and polysaccharides What are the monosacchrarides? They are simple sugars w/ 3-7 carbons The three monosaccharides are: -Fructorse, glucose, and galactose How are monosacchrarides classified? They are classified by the number of carbons in the carbon skeleton. 6C - Hetoses 5C - Pentoses 3C - Trioses What is the main monosaccharide uses in humans and plants? Glucose is the main monosaccharide we use. When a plant has too much glucose it is stored as a starch. Disaccharides -are formed when 2 monosaccharides are joined through a dehydration reaction -lactose, maltose (2 glucose), surcose (glucose+fructose) Polysaccharides -are formed when MORE than 2 monosaccharides join together -starch, glycogen, cellulose, and chitin Cellulose cell walls of plants are made of this -provides structural support to cell -its glycosidic bonds are different than in glycogen and starch -it is considered insoluble fiber Polymer A long molecule consisting of many similar or identical building blocks linked by covalent bonds Monomer Repeating units that serve as building blocks of a polymer How are monomers joined Dehydration reaction Two molecules are covalently bonded to each other, with the loss of a water molecule Describe the Dehydration Process One monomer provides a hydroxyl group (—OH), one provides a hydrogen (—H) Enzymes Macromolecules that speed up chemical reactions Monosaccharides Single sugar molecule Monosaccharides structure Usually some multiple of the unit CH2O Why are monomers packed tightly in long chains in cellulose? this shape gives cellulose its rigidity and high tensile strength Chitin -is a polysaccharide containing nitrogen -it makes up the exoskeleton of insects -also makes up fungal cell walls to help with structure Lipids -fats / oils -waxes -phospholipids -steroids Nucleus stores/protects dna, directs formation of ribosomes and proteins -nuclear envelope (double membrane) -nucleoplasm -chromatin -nucleolus (synthesizes ribosomes) Ribosomes synthesize proteins -lacks membrane -rRNA + proteins -small & large subunits -attachment sites for mRNA / tRNA DNA molecule is made up of Two long strands arranged in a double helix. Each strand is made up of four kinds of chemical building blocks called nucleotides (ATCG). Quantitative Data Data that is measurable; observations based on numbers Qualitative Data Data that is observed but not measured. Ex: color, texture, smell The major function of fats? Energy storage Phospholipids Make up cell membranes Called phospholipid bilayer Steroids Lipids Carbon skeleton consisting of four fused rings Amino Acids Organic molecules possessing both an amino group and a carboxyl group Peptide bonds are formed by? Dehydration reactions which link the carboxyl group of one amino acid to the amino group of the next. Levels of Protein Structure? Primary Secondary Tertiary Quaternary Primary Protein Structure? Sequence of amino acids connected together by peptide bonds Secondary Protein Structure? Chain of amino acids will start bending and form hydrogen bonds. 2 types: Alpha helix and Beta sheet Tertiary Protein Structure? Combination of more than one secondary structure Can be Alpha, Beta, or both Can be any type of bond formed by the R groups Quaternary Protein Structure? More than one tertiary structure react Collagens structure? Made of 3 tertiary structures braided together What Determines Protein Structure? DNA Alterations in PH Salt concentration Temperature When a protein loses it's shape it is? Denatured DNA is? Deoxy Nucleic Acid Contains directions for replication Double strand ACTG where A=T and C=G RNA is? Ribo Nucleic Acid Single strand UACG where U=A and C=G Structural difference between RNA and DNA? Located in the 5 carbon sugar. DNA is missing an oxygen. RNA and DNA linkage type? Phosphodiester Organelles Functional components of cells cohesion The phenomenon ultimately responsible for the maintenance of a column of water as it moves upward through a vessel is single bond a pair of shared electrons double bond O=O adhesion the clinging of one substance to another surface tension a measure of how difficult it is to stretch or break the surface of a liquid. colloid a stable suspension of fine particles in a liqiud pH a solution is defined as the negative logarithm of the hydrogen ion concentration starch something plants store, a polymer of glucose monomers, as granules within cellular structures Taxonomy The branch of science devoted to the classification and naming of organisms. Kingdom-phylum-class-order-family-genus-species. controlled experiment on that is designed to compare an experimental group with a control group. dalton a unit of measurement energy the capacity to cause change potential energy the energy that matter possesses because of its location or structure. electron shell is the outside part of an atom around the atomic nucleus. chemical reactions make and break chemical bonds chemical reactions change reactants into products while conserving matter. specific heat the amount of heat that must be absorbed or lost 1 g of that substance to change its temperature by 1C.