Anatomy Unit 1 part 1

Water, acids, bases, buffers, carbs

electronegativity

A molecule’s ability to attract electrons to itself

• electrons suspended within covalent bonds in molecule pulled away from hydrogen nucleus by oxygen nucleus

polarity

Distribution of electrons within a molecule resulting in a electric charge

• Hydrogen positive, oxygen negative

Hydrogen bond

Weakest bond formed from dipole moments

• Positive H attracted to negative O

Solvent

Dissolves waste and carries nutrients in and out of cells

• Polar water molecules pull ions apart via charge repulsion

lubricant

Substance used to reduce friction

Cohesion

occurs due to hydrogen bonding, happens between water molecules

adhesion

occurs due to hydrogen bonding, happens between water molecules and other polar surfaces

temperature regulator

water evaporating on skin (sweating) cools human body to protect internal organs from overheating during exercise or due to climate

Homeostasis

self regulating process by which a living organism can maintain stability

pH

• Measures acidity of solution, distinguishing between acid/base with 10x difference between numbers on scale

• Measure of H ion concentration

acid

Substance or compound that releases H ions in solution

base

• Substance or compound that takes H ions out of solution, and produces OH ions

pH of acid

pH < 7

pH of pure water

pH = 7

pH of base

pH > 7

why is pH maintenance in the human body important?

Normal pH of human blood is 7.4, and if the pH is too high or too low (too acidic/basic) then it’s fatal. This could happen when we exercise and lactic acid is released, our blood’s pH drops and if our buffer system doesn’t work properly to bring us back to 7.4, we could die.

Buffer

weak acid or base that prevent large changes in pH and keep it stable.

How do buffers act with an acid

acts as a base and takes up H ions

how to buffers act with a base

acts as an acid and releases H ions

monomer

Small building block of a molecule

polymer

Chain of monomers

dehydration synthesis

Removing water to create a covalent bond between monomers

hydrolysis

Adding water to polymer to break covalent bond

glucose

monomer of carbs

4 functions of carbohydrates

1. short term energy supply

2. long term energy storage

3. cell membrane markers

4. structural material

carb function short term energy supply example

glucose used by cells to produce energy

carb function long term energy storage example

• glycogen stored in liver, muscles

• starch stored in plants

carb function cell membrane marker example

used as “identification tags” to differentiate good from bad cells

carb function structural material example

plant cell walls = cellulose

carbohydrate empirical formula

C:H:O = 1:2:1

bond that connects glucose molecules

glycosidic bonds

starch

storage of glucose in plant cells,

• unbranched or slightly branched

glycogen

storage of glucose in animal cells

• highly branched

cellulose

component of plant cell walls

reason cellulose is indigestible for humans

alternating oxygen linkage between glucose molecules

name of 2 bonded glucose molecules

maltose

charge repulsion

2 negatives repel each other, 2 positives repel each other

pH of human blood

7.4

Human body buffer system example

exercise = lactic acid build up = body pH decreases

• if body does not have enough HCO3 or HPO, then there is metabolic problem, cannot regulate pH

property of water which makes them polar

electronegativity of oxygen

process which makes water dissolve other polar substances

charge repulsion

X, Y, Z in the diagram below would be (in order)

monomers, water, a polymer

organic polymers

molecules of life that contain carbon and hydrogen

process of water evaporation

adding energy (heat) makes water molecules vibrate, causing evaporation