bio unit 1

Atom (definition, composition, where things inside of it are located)

Atom (definition, composition, where things inside of it are located)

Basic unit of matter; composed of protons (+), neutrons (0), and electrons (-); protons and neutrons located in nucleus; electrons move around the nucleus (# of electrons=# of protons)

Neutron

Subatomic particle found in the nucleus of an atom, carrying no electric charge but contributing to the atom's mass.

Atomic Number

The number of protons in an atom's nucleus. It determines the element's identity on the periodic table.

Molecule

Two or more atoms bonded together

Compound

Two or more different atoms bonded together

Nucleus

Organelle in a cell that contains genetic material and controls cell activities.

Electron

Subatomic particle with a negative charge found in atoms, involved in chemical bonding and electricity conduction.

Element

A substance made up of only one type of atom, characterized by its atomic number and chemical properties.

What are the four common elements that make up 96% of living things?

Oxygen, carbon, nitrogen, and hydrogen

Matter

Anything that take up space and has mass

Atomic Structure

Inner to outer=2,8,8

Isotopes

Atoms of the same element that have a different number of neutrons

When the energy levels are not filled, atoms tend to react with other atoms to fill them. This is called the _____ ____.

Octet rule

Chemical Bonds

The forces that hold together atoms that make up compounds

Ionic Bond

Bond in which electrons are transferred from one atom to another

Ions

Charged atoms that have lost or gained electrons

Covalent Bonds

Bond in which electrons are shared between atoms

Polar Covalent Bond

Unequal sharing of electrons

Non-Polar Covalent Bond

Equal sharing of electrons

Hydrophilic

Water loving, ionic compounds, polar covalent

Hydrophobic

Water fearing non-polar covalent

How to find the number of neutrons

Atomic mass - atomic number

Nonstable Atom

An atom with an unstable nucleus that undergoes radioactive decay to achieve a more stable configuration.

Hydrogen Bond

Weak attraction between a hydrogen atom and an electronegative atom like oxygen or nitrogen in a molecule.

Double Bond

Type of covalent bond where two pairs of electrons are shared between two atoms, creating a stronger bond than a single bond.

Stable Atom

Has a balanced number of protons and electrons, ensuring it does not decay or undergo radioactive decay.

Does making a bond store energy or release energy?

Releases

Cohesion

Attraction between molecules of the SAME substance

Surface Tension

The property of a liquid that allows it to resist an external force due to the cohesive nature of its molecules at the surface.

Electronegativity

Electronegativity is the measure of an atom's ability to attract and hold onto electrons in a chemical bond.

Adhesion

Attraction between molecules of DIFFERENT substances

Water is a _____ ________ ________ compound.

Polar covalent molecule

Charge of Hydrogen and Oxygen

Hydrogen=+, oxygen=-

Why is water like a magnet?

Because the hydrogen has a positive pole and the oxygen has a negative pole

Hydrogen Bonding

The partial + and - charges allow H2O molecules to attract each other or stick together through hydrogen bonds

Hydrogen bonds are ____ bonds that can be ______ ______.

Weak; easily broken

Water’s Heat Capactity

Water can absorb large amounts of thermal energy before its own temperature begins to rise; water acts like a heat buffer for the globe

Ice is ____ _____ than liquid water.

Less dense

Why is water the universal solvent?

Because it can dissolve most substances

Soultion

Liquid consisting of uniform mixture of two or more substances

What are the two parts of a soultion?

Solvent (liquid (dissolving agent)) and solute (substance dissolved)

Dissasociation

Breaking apart of water molecules

If the number of ________ ____ is _______ than hydroxide ions, the solution is an ____.

hydrogen ions; greater; acid

If the number of ________ ____ is _______ than hydrogen ions, the solution is a ____.

hydroxide ions; greater; base

Buffer

Chemical substance that neutralizes small amounts of either an acid or a base

pH

pH is a measure of the acidity or basicity of a solution on a scale from 0 to 14

A beaker of acid would have more…

H + (hydrogen)

A beaker of base would have more…

OH - (hydroxide)

pH scale

Below 7=acidic, 7=neutral, above 7=basic

Activation Energy

The energy needed to get a reaction started

Catalyst

Lowers the amount of activation energy needed for a chemical reaction to begin (also known as an enzyme)

Enzyme

Proteins that speed up chemical reactions that take place in cells by lowering activation energy

Enzymes are _______.

Specific

What do enzymes typically end in?

ase

Substrate

Reactants of an enzyme catalyzed reaction

Complex

Joining together of the enzyme and substrate

How is an enzyme made?

The substrate binds to the active site which have complementary shapes (like the lock and key model)

Can enzymes be used multiple times?

Yes, as long as their active site does not change

Denatured

Protein’s shape is changed

What two factors can denature an enzyme?

pH (too high or low) and temperature (to high)

Exergonic Reaction

A chemical reaction that releases energy to the surroundings, usually in the form of heat or light.

Endergonic Reaction

A chemical reaction that requires an input of energy to proceed, typically absorbing energy from the surroundings.

Organic Chemistry

Carbon based compounds associated with living organisms

Inorganic Chemistry

Non-carbon based compounds associated with non-living things

Why is carbon a unique element?

Because of its ability to form a wide variety of molecules

Functional Groups

The non-hydrocarbon parts of the molecule

Functional groups are a cluster of _____ that influence the ________________ of the molecule they compose.

Atoms; characteristics

Hydroxyl Group

-OH

Carbonyl Group

-C=O

Carboxyl Group

-COOH (hydroxyl + carbonyl)

Phosphate Group

-PO4

Amino Group

-NH2

Monomer

Small building blocks that make up cells

Polymer

Many monomers bonded together (monomer--→polymer—→macromolecule)

Polymers are built and broken down into monomers using what two reactions?

Dehydration synthesis and hydrolysis

Dehydration Synthesis (aka condensation reactions)

A chemical reaction where two molecules combine to form a larger molecule, producing a water molecule as a byproduct.

Hydrolysis

Process of breaking down a compound by reacting it with water. Commonly used in digestion to break down large molecules into smaller ones for absorption.

Polymerization

Forming complex molecules by joining monomers together

Carbohydrates contain…

C,H,O (1:2:1 ratio)

Function of Carbohydrates

Store short term energy

Carbohydrates typically end in…

ose

Carbohydrates Functional Groups

Hydroxyl and carbonyl

Monomers of Carbohydrates

Monosaccharides

Examples of carbohydrates

Glucose (product of photosynthesis), fructose (found in fruit), galactose (found in milk)

Isomer

Compounds with the same chemical formula but different structural formulas

Polymers of carbs

Disaccharide and polysaccharide

Disaccheride

A carbohydrate molecule made up of two monosaccharides joined together through a glycosidic bond.

Examples of Disaccharides in carbs

Maltose (found in malted milkshake), sucrose (plant sap/table sugar), lactose (sugar found in milk)

Polysaccharide

A complex carbohydrate made up of multiple sugar units bonded together.

Examples of Polysaccharides in carbs

Starch (plant energy storage), glycogen (animal energy storage, muscles), cellulose (gives plants structure, cell wall, AKA fiber)

Lipid

Organic compounds that are insoluble in water but soluble in organic solvents.

Lipids contain…

C,H,O

Function of Lipids

Waterproof coverings, long term energy storage in animals, aids in insulation and protection (adipose tissue), makes up cellmembrane which is made up of phospholipids, hormones and vitamins

Monomers of Lipids are…

Glycerol and fatty acids

The glycerol portion of the lipid is _____ (__________), while the fatty acid tail is ___________ (__________).

polar (hydrophilic); non-polar (hydrophobic)

Saturated Fats

Have only single bonds between the carbons (solid at room temp.)

Examples of Saturated Fats

Butter and animal fats

Unsaturated Fats

Have at least one or more double or triple bonds between the carbons (liquid at room temp.)

Examples of Unsaturated Fats

Oils

Types of lipids

Triglyceride, phospholipid, steroids