biomolecules test

metabolism

water-based chemical reactions that convert matter and energy to sustain life

why is water the “medium for life”

Universal solvent, Reaction participant, thermal stability, Efficient transport, Chemical stability

Write the molecular formula for water and draw the atomic structure of the molecule

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polar nature of water

unequal sharing of electrons between the oxygen and hydrogen atoms

hydrogen bonds

hydrogen atom covalently bonded to a very negative atom

Contrast covalent and hydrogen bonds

Covalent bonds, which involve the sharing of electron pairs between atoms, are much stronger and more stable than hydrogen bonds, which are weaker attractions between a hydrogen atom and a more electronegative atom

Contrast adhesion with cohesion

Adhesion is the attraction between different molecules, while cohesion is the attraction between like molecules

an example of the cohesive properties of water being of benefit to life

Water’s cohesive property (tendency for molecules to stick to each other via hydrogen bonding) allows water to form a continuous column inside a plant’s xylem vessels. Without this cohesion, tall plants and trees wouldn’t be able to move water (and the dissolved nutrients it carries) from the soil all the way up to their highest leaves

capillary action

process of a liquid flowing in a narrow space without the assistance of external forces like gravity

example of the adhesive properties of water being of benefit to life

Water’s adhesive property (ability to stick to other materials) helps water molecules cling to the walls of narrow plant xylem vessels. This adhesion works together with cohesion to pull water upward against gravity. Without adhesion, the water column would slump back down instead of moving upward

effects of capillary action in soil

Moves water upward from deeper layers, Distributes moisture sideways, Retains water for longer, Supports germination

how capillary action supplies supply plants with mineral nutrients

water moves through the tiny spaces in soil (pores) from wetter areas to the plant roots, and dissolved minerals travel with it.

covalent bond

chemical bond where atoms share electrons

number and type of bonds carbon can form with other atoms

four covalent bonds with other atoms (single, double, and triple bonds)

four major classes of carbon compounds

carbohydrates, lipids, proteins, and nucleic acids

anabolism

takes smaller units like nutrients, cells, or amino acids and bonds them together to create bigger structures

catabolism

breaks down large molecules into smaller ones, releasing energy in the process

monomer

a small molecule that can chemically bond with other monomers to form a larger molecule called a polymer

polymer

a large molecule, or macromolecule, composed of many repeating subunits

condensation (aka dehydration synthesis) reactions

join two molecules by forming a covalent bond and release a water molecule

hydrolysis reactions

break a covalent bond in a molecule by adding water

simple shapes to represent monomers, diagram a condensation reaction

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(given diagrams) identify common examples of organic polymers

starch, glycogen, cellulose, proteins, DNA, and RNA

generalized chemical formula of carbohydrates

Cn​H2n​On​, where n is the number of carbon atoms

how the form of glucose fits its function in living organisms

glucose molecule is small, soluble, and easily transported in water

use of glucose polymers for energy storage in living organisms

used to store energy efficiently, as they can be broken down into glucose molecules when the organism needs fuel

how the structure of cellulose fits its function as a structural polysaccharide

Cellulose has long, straight chains of β-glucose linked by β-1,4-glycosidic bonds, which form rigid, parallel fibers held together by hydrogen bonds, giving plant cell walls high tensile strength and structural support

origin, structure, and describe the function of amylose

linear polymer of α-glucose in plants, stores energy by forming helical chains that can be broken down into glucose when needed

origin, structure, and describe the function of glycogen

highly branched polymer of α-glucose in animals, stores energy for rapid release when cells need glucose

origin, structure, and describe the function of amylopectin

a plant starch component, is a branched polymer of α-glucose with α-1,4 glycosidic bonds in the chains and α-1,6 bonds at the branch points, and it stores energy that can be quickly mobilized when needed

glycoprotein and its function

protein with carbohydrate chains attached that functions in cell recognition, signaling, and immune responses

Describe the chemical structure of triglycerides and phospholipids

consist of one glycerol molecule bonded to three fatty acids via ester bonds, forming a non-polar, hydrophobic molecule for energy storage

Describe the chemical structure of phospholipids

consist of one glycerol molecule bonded to two fatty acids and a phosphate group, giving them a polar “head” and non-polar “tails” that allow them to form cell membranes

the formation of triglycerides by condensation reactions

formed by condensation (dehydration) reactions in which one glycerol molecule bonds to three fatty acids, releasing one water molecule for each ester bond formed

differences between saturated and unsaturated (mono- or poly-) fatty acids

Saturated fatty acids have no double bonds between carbon atoms, are usually solid at room temperature, and have straight chains.

Unsaturated fatty acids have one (monounsaturated) or more (polyunsaturated) double bonds, are usually liquid at room temperature, and have kinks in their chains that prevent tight packing

outline parts of nucleotides!

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how nucleotides can connect to form a nucleic acid polymer

through phosphodiester bonds, where the phosphate group of one nucleotide links to the 3′ carbon of the sugar of the next nucleotide, creating a sugar-phosphate backbone

Compare the structure of DNA and RNA

double-stranded helix with deoxyribose sugar and the bases A, T, C, G, while RNA is usually single-stranded with ribose sugar and the bases A, U, C, G

Outline the function of base pairing

ensures accurate storage and transfer of genetic information by allowing complementary nucleotides to form hydrogen bonds, guiding DNA replication and RNA transcription

Draw the generalized structure of an amino acid

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Describe polypeptide chain formation (inc. the formation of peptide bonds and condensation reactions)

formed when amino acids join via condensation (dehydration) reactions, in which the carboxyl group of one amino acid reacts with the amino group of another, creating a peptide bond and releasing a molecule of water

Explain the infinite variety of possible peptide chains

comes from different sequences and combinations of the 20 standard amino acids

Define denaturation

the structural change of a protein or nucleic acid that disrupts its normal shape and function without breaking its primary sequence

Outline the effects of pH and temperature on protein structure

Extreme pH or temperature can disrupt hydrogen and ionic bonds in proteins, causing denaturation and loss of their functional shape