Bio Chapter 2 - The Cell

“But the plans of the Lord stand firm forever, the purposes of his heart through all generations” - Psalm 33:11

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Lesson 2.1 - Atoms + Other Building Blocks of Life

Electron - a ==negative== charge on the ==outside== of an atom

Neutron - @@no charge@@ and @@inside@@of the atom

Proton - a positive charge inside the atom and bonded to neutrons

Compound - consisting of %%two or more%% simple parts or individuals in %%combination%%

What is the compound H2SO4 made of - ^^two hydrogen^^ atoms, ^^one sulfur^^ atom, and ^^four oxygen^^ atoms

Why Does Ice Float - Ice floats because when it freezes, ==it expands== and ==binds to other water molecules== doing the same. These ==stick together== and work to ==form ice,== which is ==less dense than water.== This is important to the organisms underneath because they are ==protected from the harsh elements== by this ice and therefore can live through the winter.

Adhesion - The act of water sticking to @@other surfaces@@

Cohesion - The act of water sticking to itself

Capillary Action - The act of water using %%both cohesion and adhesion%% to supply water to the leaves of a plant

Surface Tension - Tension created by tension ^^inflicted upon the bonds of water^^ molecules

Differences - Water sticking to ==itself versus other surfaces,== water using this to ==perform an action==, and the ==use of cohesion in surface tension==

Lesson 2.2 - Water Molecule

Polar Covalent Bond - These are formed when there is an @@unequal sharing of electrons@@ between atoms

Covalent Bond - These are formed when there is an equal sharing of electrons between atoms

Why is Water a Polar Molecule - Water is polar because the hydrogen and oxygen atoms share electrons. However, the %%oxygen atom has more protons%% in its nucleus (which are positive) and %%therefore attracts more electrons%% (making it negative), although the hydrogen keeps some (making it positive). These %%uneven amounts of electrons create poles%%, which makes water polar.

How Hydrogen Bonds Form with Water Molecules - Since ^^oxygen atoms have slightly negative charges^^ and ^^hydrogen atoms have slightly positive charges^^, the two can attach to one another. This is essentially the bonding of two water molecules

Solution - A type of ==homogenous mixture== in which the particles of one or more substances (the solute) are ==distributed uniformly throughout== another substance (the solvent). The particles are too small to be seen by the naked eye, unlike in a ==suspension==, where the particles ==don’t settle== are ==big enough for the naked eye to see==

Solute - A substance that is @@dissolved@@ in a solution - Sugar in Tea

Solvent - A liquid that is able to dissolve a solid - Acetone

Acid - A compound that %%forms H+ ions%% in a solution. pH %%scale range 0-6%%, weak 4-6, strong 0-3

Base - A compound that produces ^^hydroxide ions^^ in a solution. pH ^^scale range 8-14^^, weak 8-10, strong 11-14

Neutral - A compound with a ==pH of 7==, or perfectly neutral, without leaning acidic or basic

Homeostasis - The tendency toward a relatively @@stable equilibrium@@ between interdependent elements

Buffer - Weak acids or bases that can react with strong acids or bases to prevent sharp, sudden changes in pH. These help the body to remain in homeostasis

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Lesson 2.3 - Carbon Compounds

Carbohydrates - Compounds made of %%carbon, hydrogen, and oxygen%%

• Used as a ^^main source of energy^^ in living things
• Plants use it for ==structural purposes==
• Breakdown of carbs (sugars) @@provide immediate energy@@ to cells
• Store extra sugar as complex carbs called starches
• Monosaccharides - anything that %%ends in “ose”,%% and %%includes sugars and starches%%

Lipid - Compounds made from ^^carbon and hydrogen atoms^^

• ==Not soluble== in water
• @@Fats@@, @@oils@@, @@waxes@@, and @@steroids@@
• Used to store energy and create waterproof cell membranes
• Formed when %%glycerol molecules%% are combined with %%fatty acids%%
• Fatty acids chains are formed when a ^^carbon molecule is joined with two carbon molecules^^
• A ==satured fatty acid== is formed when a ==chain is joined with a single bond==
• An @@unsatured fatty acid@@ is formed when a chain is joined with another chain or if there is @@at least one carbon-carbon double bond@@

Protein - Macromolcues that contain oxygen, nitrogen, carbon, hydrogen, and sulfur

• Made of %%amino acid monomers%%
• Amino acids have an ^^amino group on one end^^ and a ^^carboxyl group on the other^^
• There are ==20 different amino groups==
• @@Instructions@@ for amino acids to form are @@found in DNA@@
• Control the rate of reactions and regulate cell processes
• Used to %%form bones and muscles%%
• Used to ^^transport other substances^^ and ^^fight diseases^^
• There are ==four== steps to forming proteins
  • 1: Amino acids @@form a chain@@
  • 2: Amino acids are twisted to form a helix or a pleated sheet
  • 3: The chain is then %%folded into a 3D object%%
  • 4: If there is more than 1 object, the ^^two can join and create another object^^

Nucleic Acid - Macromoclues that contain ==hydrogen, oxygen, nitrogen, carbon, and phosphours==

• Made of @@nucleotide@@ monomers
• Nucleotides contain/are made of:
  • A %%5-carbon sugar%%
  • A ^^phosphate^^ group
  • A ==nitrogen base==
• When @@multiple nucleotides@@ are @@joined by covalent bonds@@, they create @@nucleic acids@@
• Used to store and transmit genetic info to cells
• RNA - %%Single%% helix & DNA - %%double%% helix

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Lesson 2.4 - Chemical Reactions + Enzymes

Chemical Reaction - A process that ^^changes one set of chemicals^^ into ^^another set of chemicals^^

During a Reaction Energy Can Be Released In - The form of ==energy==

Energy - Cannot be @@created or destroyed@@, but is @@transferred each time a chemical reaction is carried out@@. It is also needed in @@each and every chemical reaction,@@ as it is used to activate it

Plants - Get their energy from the sun (this is their activation energy)

Humans - Get their energy from %%eating plants and animals%% (this is their activation energy)

Endergonic - Energy ^^absorbed^^ in a reaction

Exergonic - Energy ==released== in a reaction

What Happens to ___ During a Chemical Reaction:

• Atoms - They are @@rearranged@@
• Compounds - They are also rearranged to fit the new set of chemicals

Product and Reactants of 2H + O > H2O:

• Products - The %%element H2O%%
• Reactants - ^^2 Hydrogen^^ molecules, ^^1 oxygen^^ molecule

Activation Energy - The energy that is ==needed to get a reaction started==

Catalyst - A substrate that @@speeds up the rate@@ of a @@chemical reaction@@. These work by @@lowering the nesscary amount of activation energy@@

Enzymes: “Ase”

• Proteins that act as biological catalysts
• %%Speed up chemical reactions%% in cells
• ^^Lower^^ing the ^^activation energy^^
• Are ==very specific== and only responsible for ==carrying out one reaction==
• @@Lact@@ase - @@Lact@@ose

Inhibitor - Something that prevents the action of an enzyme by blocking the active site so a substrate cannot enter as easily

Temperature and Enzymes - If enzymes are put in conditions that are %%too hot or cold for them to work easily,%% it will take them %%longer to produce new molecules%% and do their jobs properly

• ^^Hotter^^ Temp - Molecules move ^^too fast^^
• ==Lower== Temp - Molecules move ==too slow==
• Denaturation - 3D proteins @@losing their shape and size@@

2 Things Enzymes Do During Chemical Reactions:

• Enzymes lower activation energy
• Enzymes %%speed up a chemical reaction%%

The Steps an Enzyme Undergoes During A Chemical Reaction -

1. Substrates ^^bind to active site^^ on enzyme
2. Bond in substrate ==break/new bonds are created==
3. Products are f@@ormed and released@@
4. Enzyme is free to be used again

Enzymes Play Essential Roles In:

• %%Regulating%% cell pathways
• Making ^^materials^^ cells need
• ==Releasing== energy
• @@Transferring@@ information

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“But as for you, be strong and do not give up, for your work will be rewarded” - 2 Chronicles 15:7