The Molecules of Cells PDF Biology 1111

BIOL 1111 The Molecules of Cells Chapter 3  BIOL 1111 The Molecules of Cells Chapter 3  Learning Outcomes 1. Explain why the structure of carbon allows it to be the basis for all organic molecules. 2. Recognize hydrocarbons and structural isomers. 3. Recognize the co...

BIOL 1111 The Molecules of Cells Chapter 3  BIOL 1111 The Molecules of Cells Chapter 3  Learning Outcomes 1. Explain why the structure of carbon allows it to be the basis for all organic molecules. 2. Recognize hydrocarbons and structural isomers. 3. Recognize the common types of functional groups. Explain the biological significance of isomers and functional groups. 4. Describe the reactions involved in forming polymers from monomers and breaking down polymers into monomers. 5. Compare and contrast the 4 types of biological macromolecules, including their monomer/polymer groupings where applicable. 6. Compare and contrast starch, glycogen, and cellulose. 7. Describe the general structure of fats and phospholipids. 8. Describe the 4 levels of protein structure and the significance of denaturation. 9. Compare and contrast DNA and RNA. Understand the biological importance of base pairing. Outline 1. Organic Molecules: The Basics 2. General Structure of Large Biomolecules 3. The Four Classes of Biological Molecules Carbohydrates Lipids Proteins Nucleic Acids  Life’s Molecular Diversity is Based - on Carbon - Almost all molecules that cells make are made of carbon atoms bonded to one another and to atoms of other elements (especially H, O, and N) Carbon can make ________________, ↑ covalent bonds making it well suited to forming large diverse molecules Organic compounds are cellular molecules containing carbon and hydrogen ~ makes organic compounds  Biological molecules are based on a carbon skeleton Molecular diversity arises from variation ________ in carbon skeletons C H10 Carbon chains vary in length and shape diff shape = diff function  What are hydrocarbons? Hydrocarbons are organic molecules consisting only of C and H Many organic molecules (e.g., fats) contain hydrocarbon components Hydrocarbons can undergo reactions that release _________________ large amounts of ____________ energy  Isomers Isomers are compounds with the molecular formula same _______________ but different __________________ structures + properties Isomers are important in biology: Organisms are sensitive to subtle variations in molecules Two isomers of a drug may have __________________ different effects  Functional groups in biological molecules specific configuration of Functional group = a __________________ atoms attached to the carbon skeletons of organic molecules and involved in chemical reactions Number and arrangement of functional groups unique properties gives each molecule its ________________ All functional groups are polar, making them hydrophilic and ∴ ____________ soluble in water methyl groups impact molecular shape and _______________ function, but they are nonpolar and not reactive  Details matter! E.g., a slight change in functional O groups affects sexual development Note the placement of methyl groups * different (CH3), and carbonyl vs hydroxyl group O Outline 1. Organic Molecules: The Basics 2. General Structure of Large Biomolecules 3. The Four Classes of Biological Molecules Carbohydrates Lipids Proteins Nucleic Acids  Large biological molecules support life Cells make a diverse array of large molecules from a small set of small molecules =- Macromolecules: large molecules, often composed of thousands of covalently ______________ bonded atoms 4 classes of biologically-important molecules: Carbohydrates Lipids Proteins Nucleic acids  Most biological molecules are - polymers of unit (repeated monomers many one - Monomer = units that serve as ______________ building blocks of polymers Polymer = large molecule consisting of a chain of many identical or similar monomers strung together Carbohydrates, proteins, and nucleic acids are polymers  The variety of polymers accounts for the uniqueness of each organism The thousands of different polymers that exist to-50 monomers are made from only ___________________ ~ The near infinite number of proteins are blocks are made up only 20 amino acids (building called amino acids) DNA is made up of only 4 nucleotides The key to this variation is the sequence in which monomers are strung together  How are polymers formed from monomers? Monomers are linked together to form polymers by dehydration reactions water molecule is lost when a One monomer gives up a __________ hydrogen _________ atom and another monomer hydroxyl gives up a ________________ group Water is released as a byproduct, and covalent bond forms between a new _____________ the two monomers  How are polymers broken down? Polymers are disassembled to monomers ↑** by hydrolysis, a reaction that is the u break 3 times to break ___________ reverse of a dehydration reaction form a monomer Hydrolysis = “water break” The bond between monomers is broken by the addition of a water molecule Let’s review! What type of chemical bond is formed by dehydration synthesis? 1. Ionic bond 2. Hydrogen bond 3. Covalent bond 4. I’m not sure Outline 1. Organic Molecules: The Basics 2. General Structure of Large Biomolecules 3. The Four Classes of Biological Molecules Carbohydrates Lipids Proteins Nucleic Acids  Carbohydrates poly-many Carbohydrates include sugars, and the polymers of sugars The simplest carbohydrates are monosaccharides, or ______________ simple sugars Carbohydrate macromolecules are polysaccharides sugar > Polymers composed of many building blocks monosaccharide ________________  Monosaccharides Have molecular formulas that are multiples of (CH2O)n Can have 3-7 carbon atoms Serve as the main fuel molecules for _____________, cellular work especially glucose (C6H12O6) Most 5 and 6 carbon sugars form rings in aqueous solutions  Disaccharides 2 monosaccharides can be linked to form disaccharides - two Maltose = glucose + glucose Sucrose = glucose + fructose Lactose = glucose + galactose Polysaccharides - many Polysaccharides = polymers of 100s to 1000s of monosaccharides linked together by dehydration reactions Examples include: Starch Glycogen Cellulose  Storage Polysaccharides: Starch and Glycogen Starch = storage polysaccharide of _____________ plants animals Glycogen = storage polysaccharide of ____________ (vertebrates store liver and muscle glycogen in __________________ cells) Starch and glycogen consist of glucose monomers: Starch can be branched or unbranched Glycogen is more compact and highly branched less branches more branches  Structural Polysaccharides: Cellulose and in algae ↑ Cellulose = structural polysaccharide in plants, and a main component of ______________ plant cell walls Made of glucose monomers, but linked differently than is unbranched chains in starch and glycogen, forming ________________ covalent on Multiple unbranched chains form hydrogen bonds to ⑮Y hydrogen bonds one another to form cellulose fibers Only certain microorganisms and fungi can ________ hydrolyze it Let’s review! Which of the following functions in energy storage in animals? forms structure - Wall] 1. Cellulose (cell 2. Glycogen - storage > for plants 3. Starch 4. Glycogen and starch Let’s review! Which of the following do starch and cellulose have in common? 1. Size of their monosaccharide subunits 2. Their function when present in plants 3. The amount of hydrogen bonding that occurs between parallel strands Outline 1. Organic Molecules: The Basics 2. General Structure of Large Biomolecules 3. The Four Classes of Biological Molecules Carbohydrates Lipids Proteins Nucleic Acids  1 : 2 : / carbohydrates CH2O : lipids CH Lipids : Lipids are NOT made of monomers All lipids are hydrophobic don't interact w/ · water carbon and Lipids consist mostly of ______________ hydrogen atoms _________________ linked together by nonpolar covalent bonds ___________________ Biologically important lipids include fats, phospholipids, and steroids  Fats / Triglycerides Fats (also known as triglycerides) are made of 3 fatty acids linked to one glycerol molecule ↓ Each fatty acid is linked to glycerol via a dehydration reaction __________________ The main function of fats is _______________ energy storage  unsaturateis Fatty Acids Fatty acids vary in length (number of carbons) and in Y FS] the _________ location number and _____________ of double bonds Saturated fatty acids have ________________ · double bonds and the maximum number of hydrogen atoms possible Solid at room temperature; mainly derived from animals Unsaturated fatty acids have one or more double bonds Double bonds cause kinks in the carbon chain Liquid at room temperature; mainly derived from plants saturated unsaturated  Cis and Trans Fatty Acids It' on same side - Unsaturated fatty acids may be cis or trans, depending on whether the hydrogen atoms attached to the double bonded carbon are on same side the ___________ opposite side (trans) (cis) or ____________ of the double bond Hon opposite sides Let’s practice! Why is vegetable oil a liquid at room temperature, while butter is solid? 1. Fatty acids in vegetable oil have fewer double bonds than fatty acids in butter 2. Fats in vegetable oil have longer fatty-acid tails than fats in butter 3. Fatty acids in vegetable oil have more double bonds than fatty acids in butter 4. Fats in butter have no amphipathic character  KNOW * Phospholipids Phospholipids are similar to fats, but a __________________ phosphate group replaces one fatty acid The addition of this group makes phospholipids amphipathic (have both _____________ hydrophilic and _______________ hydrophobic regions) Form bilayers, the basis of cellular membranes  able to identify * be a steroid Steroids (in between phospholipids) ↑ steroids Cholesterol Steroids are lipids with carbon skeletons that are bent to form 4 fused rings Cholesterol, a steroid and common component animal cell membrane is the starter molecule of _________________, Testosterone for making other steroids E.g., __________, vitamins hormones bile acids, and ____________ Estrogen  A Let’s review! D Match the molecule with its name. Triglyceride Phospholipid Steroid A -B Polysaccharide - D - B C - Monosaccharide - E Outline 1. Organic Molecules: The Basics 2. General Structure of Large Biomolecules 3. The Four Classes of Biological Molecules Carbohydrates Lipids Proteins Nucleic Acids  Proteins are polymers of amino acids Proteins are essential to the structure and activities of life: proteins do things! most diverse The ________________ of the major categories of macromolecules Amino acids are the monomers of proteins There are _____ 28 different amino acids: All have the same general structure, with different R groups R group = variable chemical group, may be hydrophilic or hydrophobic  & Types of (does to be memorized not need Amino Acids Amino acids differ in their properties due to variation in the R groups side chain (_____________) (be able to recognize an amino acid) Proteins are polymers of amino acids Amino acids are linked together by dehydration reactions that result in peptide bond _________________ covalent bond that occurs between a Peptide bonds are a type of ______________ carboxyl group and an amino group The resulting ___________________ chain of amino acids that forms is a polypeptide bond forms C+ H - dehydrated  Proteins have 4 levels of structure · joined by peptide bonds 1. Primary structure: the sequence of amino acids in the polypeptide chain 2. Secondary structure: the structures that coiling/folding result from the ______________ of the polypeptide chain into local patterns (alpha helix or beta pleated sheet) hydrogen bonds Maintained by ________________ between atoms in the polypeptide backbone  Proteins have 4 levels of structure 3. Tertiary structure: the 3-dimensional shape of a protein, stabilized by interactions between R groups (e.g., hydrogen bonds, ionic bonds) 4. Quaternary structure: some proteins are multiple polypeptide composed of ___________________, 3-dimensional and the way in which these subunits associate is the quaternary structure  Protein shape and function are linked Physical and chemical conditions can affect a protein’s 3-dimensional the bonds and will structure saffect go backto a secondary structure pH and temperature E.g., Alterations in ____________________ can cause a protein to unravel Denaturation is the loss of a protein’s native (i.e., properly folded) structure A denatured protein is biologically inactive _____________  What do proteins do in cells? functions 1. Provide structural components for organisms (silk, keratin (hair)) 2. Help cells contract to move (actin, myosin) 3. Store things for cells (ovalbumin) defensive 4. Perform _______________ roles (antibodies) transport 5. ______________ substances (hemoglobin) 6. Help cells send and receive signals (neurotransmitters) 7. Carry out chemical reactions as enzymes speed->  Enzymes example of Hydrolysis disaccharide chemical Enzymes are proteins that act as ________ catalyst __________________ They change the rate of chemical being changed reactions without ______________ themselves in the process Enzymes control nearly all chemical reactions in organisms Let’s practice! Which type of bond connects amino acids together in the primary structure? 0-0-0-0-0 0- 1. Hydrogen bonds 2. Peptide bonds 3. Ionic bonds Let’s practice! True or false? 1. All proteins contain the element nitrogen. true 2. The secondary structure of a protein is a functional protein. false 3. The tertiary structure is characterized by α-helices and β-pleated sheets. true Outline 1. Organic Molecules: The Basics 2. General Structure of Large Biomolecules 3. The Four Classes of Biological Molecules Carbohydrates Lipids Proteins Nucleic Acids Nucleic Acids Nucleic acids are comprised of monomers called nucleotides The sequence of nucleotides determines the sequence of amino acids in a _____________ protein There are two main types of nucleic acids: DNA (deoxyribonucleic acid) RNA (ribonucleic acid)  Nucleotides Nucleotides all have the same general structure All have a phosphate group and a pentose sugar Nucleotides differ by having different nitrogenous bases DNA nucleotides can have one of four different bases Adenine (A) Thymine (T) Cytosine (C) Guanine (G) RNA nucleotides also have 4 different bases, but uracil (U) replaces thymine  Nucleotides dehydration Nucleic acids are made by ____________ synthesis ______________ of nucleotides The sugar of one nucleotide bonds to the phosphate group of the next monomer, resulting in a repeating sugar-phosphate backbone The sequence of bases along a DNA or RNA polymer is _________ unique for each gene  RNA and DNA RNA usually consists of a single polynucleotide strand DNA contains two polynucleotide strands, which wind together to form a double helix The two strands in DNA are held together by hydrogen bonds, according to _______________: base pairing A pairs with T rules C pairs with G The two DNA strands complementary to one another Let’s practice! Complete the complementary DNA strand. TAT CG A A T A G C T  Complementary base pairing is the key to how genetic information is passed on The same base-pair rules that result in the double helix structure of DNA also allow for DNA to provide directions for its own replication _________________ The DNA helix “unzips” and new complimentary strands are assembled along the original separated strands  Complementary base pairing is the key to how genetic information is passed on Base pairing accounts for the transcription of information from DNA to RNA, though uracil here adenine pairs with ___________, not thymine In transcription, the DNA double helix unzips and an RNA strand is assembled using one of the two DNA strands as a template Let’s practice! Which of the following is not a component of nucleotides? 1. Sugar 2. Phosphate 3. Nitrogenous base 4. Amino acid Let’s think about... The specific sequence of nucleotides in a gene is the information that programs the amino acid sequence of proteins. What would happen if scientists changed the order of nucleotides in a gene?