Biology 171 Exam 1

Polysaccharides:

"poly" = many -More than 20 covalently linked monosaccharides -Polymer of Carbohydrate

Nitrogenous Bases:

(5 different nitrogenous bases are grouped as pyrimidines or purines) 1) Pyrimidines: *Single-ringed molecules -Cytosine (C) -Thymine (T) *In DNA -Uracil *In DNA "Creepy Tombs Under PYRaMIDs" 2) Purines: *Double-ringed molecules -Adenine (A) -Guanine (G) "PURe As Gold"

What type of lipids? Protection & prevention of water loss

(ex: beeswax)

Hydrogen Bonding:

* (H-Bond) interaction between a highly electronegative atom (F, O, and N) and a hydrogen atom * Individually, H-bonds are weak, but collectively they can be quite strong.

Water:

* A small, polar molecules w 2 Hydrogen atoms & 1 Oxygen atom (H2O) * Has partial negative & positive charges (Polar covalent bond) * Recall: Hydrogen bonds form between water molecules

Which biomolecules use monomers to form polymers?

* Carbohydrates, proteins, & nucleic acids use consistent monomers to form polymers, but lipids do not

Cellular Respiration:

* Cellular Respiration: Mitochondrial process that breaks down food sources like sugars & lipids to make ATP (To memorize: "Sweat or respire when mitochondria is breaking food & making energy")

* DNA in the nucleus is __________ into RNA, which is then ________ into a protein.

* DNA in the nucleus is transcribed into RNA, which is then translated into a protein.

Endoplasmic Reticulum (ER):

* ER: Membranous structures continuous w the nuclear envelope w multiple functions. * Extension of the nucleus * ER Lumen: the internal space/compartment of the ER * Rough ER: (rER) closer to nucleus w a rough, ribosome-coated surface * Newly built proteins fold & are modified in the rER lumen * Smooth ER: (sER) further from the nucleus w a smooth, ribosome-free surface * Synthesizes/making lipids & detoxifies drugs/poisons

Ionic Bonds:

* Electrical attractions between opposite charged ions (cations & anions) * Transfer (complete transfer, not covalent- sharing) of electrons can fill the valence shells of BOTH atoms & create charges.

Functional Groups:

* Groups of atoms that are reactive/functional & commonly found together * Typically extend off the carbon backbone of a molecule.

Carbon:

* If we exclude water, carbon is the most abundant element in living systems. * Carbon is main component of organic molecules (carbohydrates, proteins, nucleic acids, & lipids) * Forms up to 4 bonds

Non-Covalent Bonds:

* Interactions between 2 atoms resulting from full or partial charges * Unlike covalent bonds, there is NO sharing of electrons in non-covalent bonds * Several types of non-covalent bonds are commonly found in biology: * 1. "STRONG" Electrostatic Interactions * Ionic Bonds * Hydrogen Bonds * 2. "weak" Van der Waals Interactions

Buffers:

* Note: pH of most living organisms is ~7 (neutral) & changing the pH even slightly can be harmful * Buffers: substances that resist changes in pH when acids/bases are added to solution. * Depending on the situation, buffers can either decrease or increase H+ in solution. * Organisms use buffets to maintain homeostasis in regards to the pH.

Nucleus:

* Protein secretion starts in the nucleus which stores DNA, the "recipe/code" for making the protein.

pH:

* a measurement of H+ concentration in a solution * pH also indirectly measures OH- in aqueous solutions

Hydrocarbons:

* organic molecules made of only Carbon & Hydrogen atoms

Aqueous Solution:

* water is a solvent * Water molecules form a hydration shell around individual solute molecules

Endomembrane System:

-A group of membrane-bound organelles inside a Eukaryotic cell -Has multiple functions including protein secretion & cellular digestion. Protein Secretion Organelles: Nuclear Envelope (Nucleus), ER, Golgi Apparatus, & Transport Vesicles Cellular Digestion Organelles: Lysosomes, Peroxisomes, Vacuoles Also: Plasma/Cell Membrane -Includes many organelles interconnected by vesicles (little membrane bubbles)

Triglycerides:

-A lipid with 3 fatty acid chains covalently linked to a single glycerol molecule -Fatty acids linked to glycerol via dehydration synthesis reactions -Triglycerides are a main source of fats: they are how fats are stored in animal cells *3 H + 3 OH → will release 3 H2O molecules during Dehydration synthesis

Denatured Protein:

-A non-functional proteins that has altered its shape -Results from changes in the environment Example: Changes in~ -pH -Temperature -Salt concentration *In pic protein is heated up, so it loses it's shape

Waxes:

-Another class of lipid that can be used for protection & prevention of water loss -They are fatty acids bound to long chain alcohol molecules Picture: *Can see structure of molecule that is beeswax. *Made of fatty acid & Long chain Alcohol *The top O used to be an alcohol hydroxyl group- but after coming to the fatty acid, the alcohol group is no longer there.

Complex Carbohydrates:

-Can slightly differ from Cn(H₂O)n -Can also have P, N, or S atoms too

Carbohydrates:

-Carbon-based molecules hydrated w many hydroxyl groups (-OH) -Also referred to as Saccharides, the Greek word meaning "sugars" -When "Carbo-hydrates" was originally coined in the 1800s, it referred to compounds w the formula Cn(H₂0)n. (Some # of Carbon molecules: "Carbo" being hydrated w some # of water molecules "hydrate")

Saturated Fatty Acids:

-Fully saturated w hydrogens (saturated meaning holding) (bc they only contains C-C: Carbon to Carbon single bonds) -Solid at room temperature -Butter, etc

Glycerol vs Glycogen?

-Glycerol: type of molecule found in living organisms that is A building block for making fats and oils-> helps to form triglycerides. (Small, sweet liquid that helps store energy in cells.) -Glycogen: the storage form of glucose in animals

Fatty Acids:

-Hydrocarbon chains of varying length w a carboxylic acid. (basically carboxyl group) -2 Main Types: Saturated Fatty Acids & Unsaturated Fatty Acids -Can be used to build Triglycerides

Lipids:

-Hydrophobic biomolecules insoluble in water that are highly diverse in their structure & function. -Can also be amphipathic: having both hydrophobic & hydrophilic groups. -Do NOT form long chains of polymers (unlike the other classes of biomolecules) -Lipids include: fat & oils, phospholipids, steroids, & waxes

Phospholipids:

-Large class of lipids that contain a phosphate group. -Major component of ALL cell membranes. -Amphipathic molecules with a hydrophilic head and a hydrophobic tail.

Steroids:

-Lipids that are made made of 4 fused carbon ring structures. (not fatty acids) -Cholesterol: Common steroid important for the structure of animal cell membranes *Cell membrane- can see phospholipids→ Embedded in between is where you see the molecules (cholesterol)

Nucleotides:

-Monomers or "building blocks" of nucleic acid polymers

Unsaturated Fatty Acids:

-NOT fully saturated w hydrogens due to presence of at least 1 C=C double bond. -Double bond creates a bend or a "kink" in the chain, making them liquids at room temp. -Vegetable oil, olive oil, etc -A subtype of unsat fatty acids is Trans Fats

Protein Secretion:

-Secretion: a process by which a substance is released into the environment/surroundings of cell -Protein secretion involves several organelles that interact w each other in a specific order.

Ribosomes:

-Sometimes ribosomes are referred to as "non-membranous organelles" -Ribosomes: molecular "machines" that build proteins in all living cells. -Ribosomes can either be "free-floating" (floating in cytoplasm) or attached to another organelle (rough ER) -Translation: the process conducted by ribosomes that builds proteins

Phosphodiester Bonds:

-The covalent bonds that link nucleotides together -Results in the sugar-phosphate "backbone". -Has directionality of 5' (5 prime) phosphate end *Can see has free phosphate 3' (3 Prime hydroxyl end) *Can see the free hydroxyl end *Can tell it's DNA by a H not 2 OH

Amino Acids:

-The monomers of proteins (Linking Amino Acid monomers together allows us to build a protein polymer) -Each amino acid monomer contains common components & unique R-group -Living organisms primarily use 20 different amino acids, each with a unique R-group

Polar Covalent Bond:

-Unequal sharing of electrons between atoms (due to different electronegativities) -Unequal distribution of electrons between atoms leads to partial (8:delta) charges

4 Biomolecules?

1) Carbohydrates (sugars) 2) Proteins 3) Lipids (fats) 4) Nucleic Acids

Carbohydrates Functions:

1) Structural Support: used to build structures Example: -Peptidoglycan: used to build cell walls of bacteria 2) Energy-Storage: used for short term energy storage Example: -Starch: used for energy storage in plants -Glycogen: used for energy storage in animals

Protein Structure Levels: #1

1. Primary: -Types, quantity, & order (sequence) of amino acids. -Arguably most important level of protein level bc.. ->Determines all other levels of structures. -Meaning if we change Primary structure, we can also change other 3 levels also. *Each circle represent amino acids in protein chained covalently linked by peptide bonds

Explain how Glucose would join together to form the disaccharide Maltose.

2 Glucose monosaccharides go through Dehydration synthesis, where H₂O is released and a Glycosidic bond covalently links the 2 together → forming the disaccharide Maltose.

Oligosaccharides:

2 to ~20 covalently linked monosaccharides "Oligo" prefix means a few -Disaccharide: 2 linked together -Trisaccharide: 3

Protein Structure Levels: #2

2. Secondary: Formation of either: -Alpha-helices (a) -Beta-sheets (B) in the protein backbone *This protein chain can then fold it's backbone into winding staircase structure: Alpha-helices or Beta-Sheets: zig zag structure

Protein Structure Levels: #3

3. Tertiary Overall 3D-shape of polypeptide chain -"Remember 3: 3D" *Can see the Alpha-helices and Beta-sheet

Protein Structure Levels: #4

4. Quaternary -Protein has multiple polypeptide chains that associate w each other to form a single, functional protein -All proteins have levels 1-3 (Primary, Secondary, Tertiary), but not all have level 4 (Quaternary)

Proteins:

A class of biomolecule polymers made of amino acid monomers -Amino acids are monomers that make up proteins

Nucleic Acids:

A class of biomolecule polymers that store/encode genetic information (ex. DNA or RNA)

What happens if a protein changes its structure or shape?

A protein will not be able to function or work -A protein's structure & shape is critical for its proper function -Structure & Shape dictates protein's function

Monosaccharide:

A single carbohydrate unit or monomers (ex: glucose) -Monomers of carbohydrates

Trans Fats:

Artificial unsaturated fatty acids that are NOT kinked (linear) -Double bond, but no kink -Burgers, french fries, etc. -Very unhealthy, should try to avoid

Hydrolysis:

Cleaves down covalent bonds to break down a polymer Lysis- breaking down *Broken by using water which is needed to break it down; water will split the polymer in half (prefix hydro)

Amino Acid Components:

Common Components found in every Amino Acid: -Central Carbon atom (Alpha carbon) -Central Hydrogen atom -Amino Group (N-terminal) -Carboxyl group (C-terminal) Differs from: -Unique R Group w different properties "R stands for Rest of the Molecule"

Peptide Bonds:

Covalent bonds linking adjacent amino acids together

DNA Function/Structure:

Deoxyribonucleic acid (DNA): -Stores genetic/hereditary information in the cell. -Forms a double-helix w 2 anti-parallel strands (directionality in diff directions) connected by base-pair hydrogen bonding. Top Strand: 5'→3' Other strand: 3'→5'

Lysosomes:

Digestive Organelle: *Recall: some of the organelles of the endomembrane system are more specialized for cellular digestion. *Lysosomes: acidic vesicles of digestive enzymes that breakdown & recycle food, debris, bacteria, etc * Primarily found only in animal cells & originate at the Golgi apparatus. *Pic: Lysosome capable of fusing w vesicle (has cellular debris in pic). Means digestive enzymes are exposed to cellular debris & they can break down debris to tiny components. (To memorize: Liars are acidic- need to breakdown & recycle them; normally Golgi/fat too)

Nonpolar Covalent Bond:

Equal sharing of electrons between atoms (due to similar electronegativities)

What type of lipids? Long-term energy storage in animals & plants.

Fats & Oils -Butter & Vegetable or Olive Oil

Simple Carbohydrates:

Fit Cn(H₂0)n formula exactly (ex. glucose)

Glucose Chemical Structure:

Follows formula to make simple carbohydrate because it has (C₆H₁₂O₆) -6 Carbon Atoms -12 Hydrogen Atoms & 6 Oxygen atoms → 6 H₂O molecules -Most abundant Carbohydrate!!

Glycogen:

Glycogen: Storage Form of glucose in animals -IE: Animal livers use as an energy-storage polysaccharide

Nucleic Acid Polymers:

Have directionality. (One end is chemically different than the other): -5' (5 prime) end -3' (3 Prime) end

Complementary nucleobases are linked together through?

Hydrogen Bonds

DNA Base Pairing (Nucleic Acids):

In DNA's structure, nitrogenous bases on different DNA strands base pair together: *A-T (DNA) *A-U (RNA) *C-G

Nucleotide components:

Nucleotide monomers consists of 3 components: 1) Phosphate Group 2) a Pentose sugar -Pentose: means has 5 member ring (can see 5 Cs in pic) 3) a Nitrogenous base -Varies: there's 5 types -Deoxyribonucleic Acid (DNA) nucleotides & Ribonucleic Acid (RNA) nucleotides use different sugars in their nucleotides. -DNA: Deoxyribose sugar "Deoxy: de is w/out; oxy is oxygen" ->One less oxygen *Can see H -RNA: Ribose Sugar *Can see OH

The sugar-phosphate backbone are formed by?

Phosphodiester Bonds

What type of lipids? Major component of cell/plasma membranes.

Phospholipids

Protein polymers:

Protein polymers have directionality: -N-terminal end -C-terminal ends -In the chain of the protein polymer, one end is chemically diff than opposite end Picture: *Joining the individual Amino Acid molecules together to form a protein polymer *The Protein polymer has directionally bc one end is chemically diff than other *End that has the Amino group: N-terminal end bc amino group has Nitrogen atom *End on opposite end is C-terminal end bc it has a Carboxyl Group (Each separate amino acids are being covalently linked together by the Peptide Bonds)

Chaperone Proteins:

Proteins that help other proteins can re-form their shape (or "re-nature") *Takes the denatured protein(on right)

RNA Function/Structure:

Ribonucleic acid (RNA): -Has a variety of functions including acting as a template for synthesizing (building) proteins. -Usually forms a single-stranded nucleotide chain. No directionality: 5'→3' *Remember uses U instead of T

Scanning Electron Microscopes (SEM):

Scanning Electron Microscope (SEM): -Visualizes external cell surfaces Memorize- "just scanning, not going too in depth or inside"

What type of lipids? Component of cell/plasma membranes & hormones.

Steroids Ex: cholesterol -Can function as hormones: testosterone & estrogen

Starch:

Storage polysaccharide which stores glucose in plants

Transmission Electron Microscope (TEM):

Transmission Electron Microscope (TEM): -Visualizes internal cell structures Memorize- Think "Transmission of a car is inside (internal) the car"

Nucleolus:

a small dense structure inside the nucleus where ribosomes & RNA are assembled

Which of the following is true of protein structure? a) Peptide bonds are formed by hydrolysis. b) Peptide bonds join the amine group on one amino acid with the R group of another amino acid. c) Secondary protein structures are caused by hydrogen bonding between atoms of the peptide backbone. d) Tertiary protein structure emerges when there is more than one polypeptide in a protein.

a) hydrolysis= breaking so no b) Peptide Bond= between Carboxyl group of Amino Acid #1 + Amine Amino Acid #2 (nothing to do w R group) c) Secondary protein structures are caused by hydrogen bonding between atoms of the peptide backbone.

Organic molecules:

any molecules w covalently linked carbon & hydrogen atoms.

What is the difference between the sugar group in DNA and the sugar group in RNA? a) The sugar group in DNA is a hexose, while the sugar group in RNA is a pentose. b) The sugar group in DNA has an extra hydroxyl group than the sugar group in RNA. c) The sugar group in DNA has one less hydroxyl group than the sugar group in RNA. d) The sugar group in DNA contains one less carbonyl group than the sugar group in RNA. e) The sugar group in DNA and RNA are not different.

c) The sugar group in DNA has one less hydroxyl group than the sugar group in RNA.

Solution:

combination of solutes & solvent

Nuclear Envelope:

double membrane that surrounds the nucleus & acts as the barrier

Animal cells store energy in the form of _________, and plant cells store energy in the form of ___________. a) Sucrose ; glucose. b) Disaccharides ; monosaccharides. c) Starch ; glycogen. d) Cellulose ; chitin. e) Glycogen ; starch.

e) Glycogen ; starch.

Dehydration Synthesis:

forms covalent bonds to link individual monomers & build a polymer Hydroxyl (OH) group of one monomer reacts w + a Hydrogen (H) on another molecule → to release a water H₂O molecule (Dehydrating the molecule bc losing water molecule to form polymer) (Synthesizing/building polymer)

Chitin:

found in the exoskeletons of insects and crustaceans (ex. lobsters)

Ways to describe Length of Amino Acid Chains:

functional is last one -Don't remain as chains: they folded up and become 3-D structures

Water is described as the "Universal Solvent" bc?

it can dissolve SO many solutes

Polymers:

long chains of many monomers linked together

Dehydration Synthesis: links ______ together to _____ polysaccharides.

monosaccharides together to build polysaccharides

Cellulose:

most abundant carbohydrate (polysaccharide) found in plant cell walls

Dehydration Synthesis: link ________ together to _____ nucleic acid polymers.

nucleotides; build

Monomers:

single indivisible building blocks that can be repetitively linked together to form polymers * Monomers will vary depending on the type of biomolecule polymer

Glycosidic Bonds:

the covalent bonds that link monosaccharides (a single carbohydrate unit or monomers) together

Solvent:

the substance that does the dissolving, usually found in larger amounts (usually water)

Solute:

the substance that gets dissolved by the solvent, usually found in smaller amounts

Nuclear Pores:

tiny "holes" in nuclear envelope that allow entry/exit into & out the nucleus