Chemistry Comes Alive (Ch. 2) Flashcards
matter
- a physical substance that occupies space and has mass
- can be solid, liquid, or gas
elements
- composes all matter
- can’t be broken down into simpler substances by ordinary chemical methods
- made up of building blocks called atoms
atoms
- smallest units of matter
- make up all elements
- non-living
- made up of subatomic particles
subatomic particles
- nucleus: central core of an atom
- protons: (+) charged particles
- neutrons: not charged
- electrons: (-) charged particles that orbit the nucleus
molecules
since most atoms don’t exist in their free state, they’re usually combined and held together with other atoms by chemical bonds
ex: O2
compounds
molecules can contain multiple elements
ex: H2O
solutions
- homogenous mixtures of components
- can be solid,liquid, or gas
- same composition throughout
solvent
substance present in the greatest amount
- acts as dissolving medium
- almost always a liquid
- water is the most common
solute
substances present in smaller amounts in a solution
water
- most important compound in human body
- makes up approx. 60-80% of body weight
- POLAR MOLECULE
- has (+) & (-) charged ends or poles
ions
charged atom that has gained or lost electrons
- also known as electrolyte
- an atom that LOSES electrons becomes positively charged
- positive charged ions are called cations
- an atom that GAINS electrons becomes negatively charged
acids
an electrolyte that releases hydrogen ions mixed with water
- proton donor
- sour tasting, react with metals
bases (alkaline)
electrolyte that releases hydroxyl ions when added to water
- proton acceptors
- bitter tasting, slippery to the touch
pH
measurement of the relative amounts of hydrogen ions in a solution
tells you how acidic or basic a solution is
- pH scale is from 0-14
- neutral: has an equal number of hydrogen & hydroxide ions
- acidic: numbers below 7
- basic: numbers above 7
buffers
systems that help to maintain the homeostasis values of pH in the body
- resisting acidic changes by binding molecules to H+
- resisting basic changes by releases H+ molecules
organic compounds
compounds that contain carbon
- carbohydrates
- proteins
- lipids
- nucleic acids
carbohydrates
building blocks of carbs: carbon, oxygen, hydrogen
function: provide a readily available, easily used source of energy for cells
types of carbohydrates:
- monosaccharides
- disaccharides
- polysaccharides
monosaccharides
“one sugar” “simple sugars”
classified by number of carbons they contain
⇢ hexose sugars (6 carbons)
⇢ pentose sugars (5 carbons)
- glucose
- fructose
- galactose
- ribose
- deoxyribose
disaccharides
- “double sugar”
- created when 2 monosaccharides join together
- too large to pass through cell membranes of digestive system cells
polysaccharides
multiple simple sugars linked together
large, almost insoluble
- makes them ideal for storing materials
- starch is the storage carb formed by PLANTS
- glycogen is the storage carb formed by ANIMALS
lipids
“fats”
insoluble in water
building blocks of lipids: carbon, hydrogen, & only a few oxygen atoms
function: good source of energy storage, hormone production & cell structure
- triglycerides
- phospholipids
- steroids
triglycerides
found in tissue under the skin & around organs
function: protect & insulate the body, long-term storage of energy
phospholipids
modified triglyceride
1 HYDROPHILIC HEAD & 2 HYDROPHOBIC TAILS
function: primary component of cell membrane structure
steroids
consist of 4 interlocking hydrocarbon rings
function: produce hormones
most important steroid: CHOLESTEROL
- found in cell membranes
- raw material used for vitamin D synthesis, bile salts
- produces steroid hormones such as estrogen, progesterone, aldosterone, testosterone
proteins
function: provide structure in body, acts as enzymes
building blocks of proteins: amino acids
can display different levels of structure depending on # of bonds:
primary secondary, tertiary
amino acids
20 different types of amino acids
proteins are long chains of amino acids linked by peptide bonds
enzymes
proteins that act as catalysts in chemical reactions
speeds up chemical rxn up to 10Bx faster than the rxn would occur without them
we’d be dead w/o enzymes
nucleic acids
largest organic molecules/compounds in the human body
types of nucleic acids:
RNA⇢ Ribonucleic Acid
DNA ⇢Deoxyribonucleic Acid
ATP ⇢Adenosine Triphosphate
Nucleotides
building blocks of nucleic acids
DNA ⇢ Adenine, Thymine, Cytosine, Guanine
RNA ⇢ Adenine, Uracil, Cytosine, Guanine
ATP
Adenosine Triphosphate
ATP = ENERGY
function: transfers energy for cell activities
- very important nucleic acid for humans
- “energy currency” of all living systems
