AP BIOLOGY AP EXAM FLASHCARDS (under construction! 🏗️🚧👷)

Covalent Bonds

electrons that are shared between atoms; most common in living things.

Polar Covalent Bonds

electrons are unequally shared between atoms & are attracted to one nucleus more than the other. (hydrophobic)

Nonpolar Covalent Bonds

electrons are equally shared between atoms; forms between similar electronegativity. (hydrophilic).

Ionic Bonds

atoms “receive” or “donate” electrons resulting in an electrostatic attraction between atoms of opposite charges.

Hydrogen Bonds

a hydrogen bond w/ a partial positive charge interacts w/ an atom w/ a partially negative charge.

• Occurs when hydrogen forms a polar covalent bond w/ another atom causing hydrogen’s electrons to be pulled in one direction leaving the positively charged nucleus exposed.

Glycosidic Bonds

Covalent bonds between monosaccharides to make polysaccharides or starch.

Ester Bonds

forms when a hydroxyl group on a glycerol head & a carboxyl group of the fatty acid tails; using dehydration synthesis.

Peptide Bonds

Covalent bonds between amino acids to make polypeptides.

Phosphodiester Bonds

Covalent bonds between nucleotides that link them together in DNA & RNA molecules.

• DNA is double-stranded

• RNA is single-stranded

Acids

• Acids release H⁺ ions when dissolved in water.

• The presence of excess H⁺ ion in a solution makes it acidic.

• Acids can be identified by the ability to donate protons.

Bases

• Bases releases OH ions when dissolved in water.

• The presence of excess OH ions makes a solution basic.

• Bases can be identified by the ability to accept protons

pH Scale & Formula

1-7 = Acidic

7-14 = Basic

7 = Neutral

pH = -log [H^+]

What is the basic structure of water?

Why is water a polar molecule?

How does water form hydrogen bonds?

Why is water considered the ultimate solvent?

Cohesion

When 2 of the SAME water molecules form hydrogen bonds w/ each other.

Adhesion

When 2 DIFFERENT molecules form hydrogen bonds w/ each other.

Surface tension

Is due to the hydrogen bonding at the surface of water.

Capillary action

Driven by the adhesive & cohesive properties of water.

Ex ~ helps plants draw water from the soil.

High heat capacity in water

Due to waters attractions between water molecules, it takes a long time to cool & heat.

High heat of vaporization

Due to iwaters Hydrogen bonding, it takes more heat to vaporize.

Solvent properties of water

Water can dissolve polar molecules & ionic compounds.

Monomers

Chemical subunits used to create polymers.

Polymers

Macromolecules are made up of many monomers.

• A covalent bond is formed between 2 interacting monomers.

Dehydration Synthesis

a reaction in which monomers are joined together w/ a covalent bond when water is removed.

• Builds polymers (macromolecules) from monomers.

Hydrolysis Reaction

a reaction in which covalent bonds within polymers are cleaved (broken down) when water is added.

• Breaks polymers (macromolecules) to monomers.

Carbohydrates’ Elements (& Ratio)

CHO ( Carbon, Hydrogen, Oxygen); 1:2:1 ratio

• Ex: simple sugars (C₆H₁₂O₆)

• N & P are sometimes present as well.

Monomers of Carbohydrates (& what they contain)

Monosaccharides

• All contain a hydroxyl group (OH) & a carboxyl group (O double bonded to C).

Function of Carbohydrates

Function: provides energy to cells & forms rigid structures in cell walls (i.e. cellulose in plants).

Lipids’ Elements

CHO (Carbon, Hydrogen, Oxygen)

Monomer of Lipids

glycerol head (hydrophilic) & fatty acids (hydrophobic).

Saturated Fatty Acids

Does not contain double bonds, causing the structure to be a straight chain.

• It “saturates” carbon backbones w/ hydrogen atoms.

Unsaturated Fatty Acids

Does contain double bonds, causing the structure to be a kinked chain (where there is a double bond).

Function of Lipids

Function: long-term energy storage molecule for cells & is used in cell communication (hormones).

• ALL Lipids are hydrophobic.

Phospholipids

glycerol head (hydrophilic) & fatty acids (hydrophobic) ALONG W/ a phosphate group.

Function of Phospholipids

Function: major component in the building blocks of cell membranes.

Triglycerides

A type of NONPOLAR lipid formed by esterification.

• Unlike phospholipids, they have 3 fatty acids bonded to a glycerol head.

• Therefore, for every 1 of _______, to form, 3 water molecules are released.

  • (H from glycerol head combines w/ an OH from a fatty acid to make H₂O).

Function of Triglycerides

Function: A type of lipid for energy storage.

Proteins’ Elements

CHON (Carbon, Hydrogen, Oxygen, Nitrogen)

• (sometimes contains a small amt. of sulfur)

Monomer of Proteins

Amino Acid (-NH₂)

• Made up of -NH₂ group, carboxylic acid group, hydrogen atom, & an R group.

  • The sequence/type/# of amino acids within a protein determine its shape & its function.

  • 20 diff. types of amino acids found in polypeptides.

Function of Proteins

Function: SSTRCC (storage, structure, transport, regulation, contractile, catalysts)

Protein Structures

Primary, Secondary, Tertiary, Quaternary.

Primary Structure of a Protein

the sequence of amino acids that determine HOW the protein will fold.

*Not affected by Denaturation*

Secondary Structure of a Protein

the structure that results from the hydrogen bonding in the polypeptide backbone.

• Two types of backbones: alpha helix & beta sheet.

Tertiary Structure of a Protein

the 3D shape of a single polypeptide chain that determined the function of the protein.

• Includes loops/turns in the backbone that allow R groups to sit next to each other & form bonds.

Quaternary Structure of a Protein

arises from the interaction between 2+ polypeptide chains, each w/ its own tertiary structure.

Nucleic Acids’ Elements

CHONP (Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus)

Monomer of Nucleic Acid

Nucleotides.

• Made up of… 5-carbon sugar (deoxyribose or ribose), a phosphate group (acidic & neg. charge), & a nitrogenous base.

Function of Nucleic Acids

Function: sequence of nucleotides store genetic information.

Eukaryotes

Prokaryotes

bacterial cell w/ no defined nucleus & no membrane-bound organelles.

Eukaryotes

more complex cell w/ a defined nucleus & organelles; also has a cytoskeleton.

Characteristics of All Cells

• Plasma Membrane

• Nuclear Region

• Cytoplasm

  • Contains sugars/amino acids/proteins (divided into organelles in eukaryotes)

• Ribosomes

  • Found in all life forms, signs of common ancestry of all living things

  • In Eukaryotes, the ribosome is found in the endoplasmic reticulum

  • In Prokaryotes, the ribosome is floating around in the cytoplasm.

Modern Cell Theory (3 things)

1. All organisms are composed of cells

2. Cells are the basic units of structure & function

3. All cells come from other cells.

Cell Size of Prokaryotes

1-10 micrometers (small)

Cell Size of Eukaryotes

10 micrometers-5 cm (slightly larger bc their organelles allow for compartmentalization)

Compartmentalization

seperation of diff cellular processes/interactions/rxns by organelles/membranes.

Surface Area to Volume Ratio

• Smaller cells have a higher SA:V;easier for materials to diffuse into/out of the cell

• Larger cells have a smaller SA:V; takes longer for materials to diffue into/out of the cell.

PROKARYOTES: Cell Envelope (3 things)

1. semi-permeable plasma membrane

2. cell wall (to maintain shape due to lack of cytoskeleton)

3. glycocalyx (to prevent drying out)

PROKARYOTES: Cytoplasm (3 things)

1. nucleoid region (co

2. ribosomes (in cytoplasm)

3. thykloid membranes (in cyanobacteria to perform photosynthesis)

PROKARYOTES: Appendages (3 things)

made out of proteins

1. Flagella (moves through rotation)

2. Fimbriae (bristles to attach to surfaces)

3. Sex Pilli (for DNA exchange via conjugation)

Conjugation

the transfer of DNA from one bacterium to another (via sex pilus)

* increases genetic diversitt betwee

Domain Bacteria 3 Shapes

1. Coccus (sphere)

2. Spirilla (spiral)

3. Bacillus (rod)

Domain Bacteria Plasma Membrane

phospholipid bilayer made out of phosphate & fatty acid tails

Domain Bacteria Cell Wall

Peptidogyclan

Domain Archaea Characteristics

Diverse in shape & DNA/RNA of archaea are more similar to eukaryotes than to bacteria.

Domain Archaea Plasma Membrane

phospholipid bilayer made of phosphate, glycerol, & hydrocarbons.

Domain Archaea Cell Wall

polysaccharides & proteins

Organelles

membrane-bound compartments

Theory of Endosymbiosis

organelles were once free-living bacteria that were engulfed by larger eukaryote cells.

• Almost all organelles resemble bacteria in shape/size

• Organelles have double membranes

• Separate DNA has been found in mitochondria/chloroplast

Cell Wall

found in prokaryotes/plants/fungi; provide a structural boundary & permeability barrier; made up of complex carbs.

Ribosome Structure

Consists of a large & small subunit composed of proteins & ribosomal RNA (rRNA).

Either freely in the cytoplasm (of all cells) or bound to the ER to form the rough ER (only in eukaryotic cells)

Ribosome Function

the site of protein synthesis

Endoplasmic Reticulum (ER) Structure

series of membrane-bound channels in the cytoplasm in the eukaryotic cell.

Endoplasmic Reticulum (ER) Function

important role in protein synthesis using ribosomes bound to its membrane; provides some support of the role of the cytoskeleton.

Rough Endoplasmic Reticulum (RER) Structure/Function

Structure: (1) studded w/ ribosomes & (2) formed from continuous folds of the membrane w/ (3) a nuclear envelope.

Function: processes proteins (packaging newly synthesized proteins) made by the ribosome to then export them.

Smooth Endoplasmic Reticulum (SER) Structure/Function

Structure: not studded w/ ribosomes.

Function: involved in the production/processing/storage of lipids/carbs/steroids.

Golgi Complex/Apparatus Structure

series of flattened membrane-bound sacs (called cisternae); similar to SER

Lumen

the interior part of each cristerna (in the golgi complex); holds necessary enzymes for the Golgi to function.

Golgi Complex/Apparatus Function

modifies proteins & lipids (from the ER) before packaging them into golgi vesicles.

• the vesicles then transport the proteins & lipids to their required destination.

Protein Trafficking (through Golgi Complex)

• Exported (i.e. hormones such as insulin)

• Put into lysosomes (such as hydrolytic enzymes)

• Delivered to membrane-bound organelles.

Mitochondria Structure

• surrounded by a double membrane w/ the inner membrane highly folded to form cristae.

• Matrix: the central part of the mitochondrion which is formed by the cristae; contains enzymes needed for aerobic respiration.

• Outer-membrane: smooth

• Inner-membrane: highly convoluted (=folded)

Mitochondria Function

the site of aerobic respiration within eukaryotic cells.

• The folding of the cristae increases the surface area (to allow for more ATP to be synthesized)

• The double membrane allows proton gradients to form across the membranes.

• Proton gradients are important in the production of ATP.

Lysosomes Structure

Lysosomes are membrane-enclosed sacs which contain digestive (hydrolytic) enzymes. 

Lysosomes Function

• To break down waste materials (worn out organelles) & cellular debris.

• Immune System to destroy pathogens.

• Apoptosis: programmed cell death when a cell is very worn out.

Vacuoles Structure

Sacs found in both plant & animal cells.

• more larger & prominent in plant cells compared to animal cells.

Vacuoles Function

• Function in Plant Cells: plays an essential roles in storing water/nutrients, maintaining turgor pressure,   & degrading waste products.

• Function in Animal Cells: plays a role in intracellular digestion & storage & release of various molecules (macromolecules & cellular waste).

Chloroplasts Structure

• Surrounded by a double membrane (much larger than mitochondria).

• Membrane-bound compartments called thylakoids containing chlorophyll stack to form structures called grana.

  • Grana are joined together by lamellae (thin/flat thylakoid membranes).

Chloroplasts Function

the site of photosynthesis in harnessing light energy & converting stored chemical energy in the form of food.

Membranes

• form partially permeable barriers between the cells.

• Substances can cross _________ by passive/active transport.

Phospholipids Monolayer

• Basic structure of the membrane.

• Formed by a hydrophilic phosphate head bonding w/ 2 hydrophobic hydrocarbon (fatty acid) tails.

  • Amphipathic: both the hydrophobic & hydrophilic part.

Phospholipids Bilayer

• a double layer of phospholipids w/ hydrophilic heads facing inwards & outwards & hydrophobic tails between the heads

• Loosely held together by weak hydrophobic interactions (to maintain membrane fluidity).

Fluid Mosaic Model

• “Fluid”: bc the phospholipids/proteins can move around in their own layers.

• “Mosaics”: bc the scattered pattern produced by the proteins in the phospholipid bilayer look somewhat like a mosaic when viewed from above.

Cholesterol in the Plasma Membrane

Function in the Plasma Membrane: stiffens & strengthens membrane

Proteins in the Plasma Membrane

Function in the Plasma Membrane: Peripheral for structure; Integral is embedded in membrane, but can move laterally. 

• Some span membranes: (transmembrane proteins).

Glycoproteins & Glycolipids in the Plasma Membrane

carb chains attached to protein or phospholipids.

Function in the Plasma Membrane: adhesion, reception, cell recognition.

Integral Proteins

partially hydrophobic & therefore embedded in the phospholipid bilayer.

Peripheral Proteins

hydrophilic & therefore are temporarily attached to the surface of integral protein/plasma membrane.

Channel Proteins

allows molecules to pass through