Studied by 69 people
Topics: H2O, general chemistry (pH, buffer, etc.) - Carbohydrates Not included: Redox Questions: Matching - terminology, molecule ID Word relationships (pick the odd one out, good explanation why) Longer answer - draw dehydration synthesis OR hydrolysis reaction (don’t need to memorize shape of molecules, will be provided on quiz) Sketch H2O molecule(s) - Properties of H2O -> relate polarity, cohesiveness, adhesiveness, etc to a given property OUT OF 12
dehydration synthesis
A chemical reaction in which two molecules are bonded together with the removal of a water molecule.
What are the structural differences between glycogen, cellulose and starch?
Glycogen: highly branched
Cellulose: rigid, straight
Starch: slightly branched
Simple sugars (monosaccharides)
building blocks of carbohydrates; glucose, fructose, galactose
all isomers of eachother
Polysaccharides
Carbohydrates that are made up of more than two monosaccharides
hydration shell
water molecules that surround an ion during dissociation (disolving ionic compounds) → stabilizes ions in solution and prevents them from recombining
dissociation
the process by which an ionic compound breaks apart into its individual ions when dissolved in a solvent like water
Starch
A storage polysaccharide in plants consisting entirely of glucose.
- somewhat branched
Glycogen
storage form of glucose in animals
- branched
Cellulose
Carbohydrate component of plant cell walls. - rigid, straight
Lactose = ______ + ______
glucose + galactose
maltose = __ + __
glucose + glucose
sucrose = __ + __
glucose + fructose
Four types of macromolecules
carbohydrates, lipids, proteins, nucleic acids
Four reasons why water is vital for life
- high heat of absorption (allows large bodies of water to maintain constant temperature)
- freezes from top -> down (protects organisms living in ponds/lakes)
- acts as a solvent, dissolves other polar molecule (it transports nutrients + waste in organisms, facilitaes chemical reactions, maintains structure/function of cells)
- adhesive + cohesive qualities
water's adhesive properties
- Water molecules are polar, with partial positive and negative charges. This polarity allows them to form hydrogen bonds with other polar or charged surfaces, leading to adhesion.
- helps in capillary action, where water moves through narrow spaces against gravity. This is vital for plants, as it allows water to travel from the roots up through the xylem to the leaves, facilitating nutrient and water distribution.
water's cohesive properties
- Water’s attraction to itself, causing molecules to stick together. They're polar and form hydrogen bonds with each other. This results in high surface tension and the tendency of water to form droplets.
- cohesion helps maintain the structure of cellular fluids and supports the formation of cellular membranes.
surface tension
The force that causes the surface of a liquid to act like a stretched elastic sheet, minimizing its surface area.
Why It Happens: Molecules at the surface of a liquid experience stronger cohesive forces inward because they are not surrounded by other molecules on all sides, creating a “skin” that resists external forces.
what's the relationship between water's high specific heat and its resistance to temperature changes?
it can absorb and release large amounts of heat with only small changes in temperature. This property makes water resistant to rapid temperature changes, helping to stabilize temperatures in both the environment and within organisms.
evaporative cooling
The process in which the surface of an object becomes cooler during evaporation, a result of the molecules with the greatest kinetic energy changing from the liquid to the gaseous state.
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what allows ice to float on water?
its solid form is less dense than its liquid form due to the arrangement of water molecules in a crystalline structure, which creates more space between them.
solvent
A liquid substance capable of dissolving other substances
solution
A homogeneous mixture of two or more substances
solute
A substance that is dissolved in a solution.
how does water dissolve ionic compounds
The hydrogen in the water pulls off the negative ion, and the oxygen in the water pulls off the positive ion. This causes the ions to split up, and for the compound to become dissolved.
hydrophobic
Having an aversion to water; tending to coalesce and form droplets in water.
hydrophilic
Having an affinity for water.
buffer
compound that prevents sharp, sudden changes in pH
- maintains pH and homeostasis in living beings
carbohydrates contain
carbon, hydrogen, oxygen
Ratio of carbohydrates
1 carbon: 2 hydrogen: 1 oxygen
hydrolysis
Breaking down complex molecules by the chemical addition of water
polysaccharides
Carbohydrates that are made up of more than two monosaccharides
examples of polysaccharides
starch, glycogen, cellulose
when acids dissociate, ___ are released
H+ ions
when bases dissociate, ___ are released
OH- ions
disaccharides
double sugars
formation of these sugars through dehydration synthesis (removal of water to join 2 molecules)
relationship between sucrose, lactose, galactose
they are all isomers of each other
using surcose and its constituent simple sugars, show a hydrolysis reaction
sucrose + water → glucose + fructose
using maltose and its constituent simple sugars, show a dehydration synthesis reaction
glucose + glucose → water + maltose
