Review Flashcards: Cells, Biomolecules, Water, Enzymes, and Endosymbiosis

Fill-in-the-blank flashcards to review key terms and concepts from the lecture notes.

The three parts of the Cell Theory are: All living things are made of , Cells come from , and Cells are the of life.

cells; pre-existing cells; basic unit

Prokaryotes have no and no .

nucleus; membrane-bound organelles

Eukaryotes have a and .

nucleus; membrane-bound organelles

The organelle that controls cellular activities is the .

nucleus

The structure that selects what enters or leaves the cell is the .

cell membrane (plasma membrane)

The organelle that turns food into energy the cell can use is the .

mitochondrion

The organelle that makes proteins is the .

ribosome

The organelle that stores materials is the .

vacuole

The organelle that breaks down worn out parts/cell death is the .

lysosome

The organelle that makes proteins used outside of the cell and transports them is the .

rough endoplasmic reticulum

The organelle that makes lipids is the .

smooth endoplasmic reticulum

The organelle that modifies, sorts and packages proteins is the .

Golgi apparatus

The tough and rigid structure that supports plant cells (bacteria, fungi, protists too) is the .

cell wall

The organelle that turns light energy into sugars is the .

chloroplast

Found only in animal cells (used in cell reproduction) is the .

centriole (in centrosome)

Polar molecule - The distribution of is uneven within the molecule.

electrons (electronegativity causes partial charges)

Valence electrons - The electrons in the outermost energy level are called .

valence electrons

Ionic bond - An ionic bond is a bond formed when electrons are from one atom to another.

transferred

Covalent bond - A covalent bond is a bond formed when atoms electrons.

share

Hydrogen bond - A hydrogen bond is a weak bond between a hydrogen atom and a more electronegative atom such as .

oxygen (or nitrogen)

Cohesion - Cohesion is the attraction between molecules.

like (the same substance)

Adhesion - Adhesion is the attraction between substances.

different (two or more different substances)

Surface tension (H2O) - Water's surface tension is due to bonds among water molecules at the surface.

hydrogen

Phagocytosis - Phagocytosis is a form of endocytosis where the cell engulfs .

large particles

Endosymbiosis - Endosymbiosis is the theory that originated from intracellular bacteria.

mitochondria and chloroplasts (originating as prokaryotes)

Hydrolysis - Hydrolysis is a reaction that water to break apart molecules.

uses water

Dehydration synthesis - Dehydration synthesis is a reaction that a water molecule to join monomers.

removes (produces)

Explain why water is a polar molecule.

Oxygen is more electronegative than hydrogen, creating an unequal distribution of electrons and partial charges.

Why can a water strider walk on water?

Hydrogen bonding creates surface tension that supports the insect on the water surface.

Explain how you 'dented' water. What properties/forces are involved?

The surface forms a 'skin' due to surface tension arising from cohesion (hydrogen bonding); adhesion to surfaces can modify the meniscus.

Name the 4 groups of biomolecules, then name the monomer and polymer of each one.

Carbohydrates: monomer = monosaccharide; polymer = polysaccharide. Proteins: monomer = amino acid; polymer = polypeptide. Nucleic acids: monomer = nucleotide; polymer = polynucleotide. Lipids: monomer = glycerol + fatty acids; polymer = none (no true polymer)

What does The Endosymbiotic Theory explain?

That mitochondria and chloroplasts originated as free-living prokaryotes that were engulfed by a host cell.

Who put the Endosymbiotic Theory together?

Lynn Margulis (often cited with idea extended from earlier researchers)

The Endosymbiotic Theory provides evidence that mitochondria and chloroplasts have their own and replicate by .

DNA; binary fission

Stores your genetic information and lets you pass it on to your kids - The biomolecule is .

DNA

Part of cell membranes, act as hormones, insulate, long term energy stores - The biomolecule class is .

lipids

Speed up chemical reactions, fight infection, make structures, movement - The biomolecule class is .

proteins

Energy source for most organisms, make up cell walls - The biomolecule class is .

carbohydrates

RNA and DNA are polymers made of repeating units called .

nucleotides

Are cellulose, chitin, and chitosan examples of polymers or monomers that form structures?

They are polymers (polysaccharides or polysaccharide derivatives) built from sugar monomers (e.g., glucose for cellulose)

Cellulose is a polymer of used by plants for cell walls.

glucose (beta-1,4-glycosidic bonds)

Chitin is a polymer of found in fungal cell walls and insect exoskeletons.

N-acetylglucosamine

Chitosan is a deacetylated derivative of .

chitin

Enzymes are catalysts and are mostly made of .

proteins

What is the induced fit model?

The enzyme changes shape slightly to better fit the substrate after binding.

How do enzymes speed up chemical reactions?

By lowering the activation energy and stabilizing the transition state, often by properly orienting substrates in the active site.

What factors affect how enzymes work?

Temperature, pH, enzyme concentration, substrate concentration, presence of inhibitors or cofactors, and denaturation.

What is denaturing?

Loss of an enzyme's or protein's shape and function due to heat or extreme pH.

Why is there usually only one substrate that an enzyme can act on?

Enzymes have a specific active site whose shape and chemistry fit only particular substrates (substrate specificity).

Catabolic vs. anabolic reactions - Catabolic reactions ; Anabolic reactions .

break down molecules; build up molecules

Label the parts of an enzyme-substrate diagram: the region where the substrate binds is the ; the molecule that is the substrate is the ; the combination forms the ; the products are the .

active site; substrate; enzyme-substrate complex; products

Total magnification on a microscope is calculated as: .

Total magnification = eyepiece magnification × objective magnification

Be able to identify ionic, covalent, and hydrogen bonds: Ionic bonds involve of electrons, Covalent bonds involve electrons, and Hydrogen bonds are weak attractions between a hydrogen atom and another electronegative atom.

transfer; sharing; interactions (often with O, N, or F)

What is the chemical basis for water being polar?

Oxygen is more electronegative than hydrogen, creating partial negative charge on O and partial positive on H.

What are cohesion, adhesion, and surface tension in water?

Cohesion = attraction between like molecules; adhesion = attraction between different substances; surface tension = cohesive forces at the surface of a liquid.

What property is particularly notable as a water-specific feature?

High surface tension and high heat capacity/heat of vaporization due to extensive hydrogen bonding.

What is an ion?

An atom or molecule with a net electric charge due to loss or gain of electrons.

Hydrogen, ionic and covalent bonds - know what each type is: Ionic bond involves transfer of electrons; Covalent bond involves sharing electrons; Hydrogen bonds are weak attractions between a hydrogen atom and an electronegative atom.

Ionic: transfer of electrons; Covalent: share electrons; Hydrogen: weak attraction involving H and electronegative atom