e1-1 Flashcards
Blue Word
Definition
prokaryote
A single-celled organism without a nucleus or membrane-bound organelles (e.g., bacteria and archaea).
eukaryote
A cell or organism that contains a nucleus and membrane-bound organelles.
bacteria
A domain of prokaryotic microorganisms that can be beneficial or pathogenic.
plasma membrane
A selectively permeable lipid bilayer that surrounds the cell, controlling what enters and exits.
cytoplasm
The gel-like substance within a cell that contains organelles, enzymes, and molecules necessary for cellular function.
cytosol
The aqueous component of the cytoplasm where organelles and molecules are suspended.
organelles
Specialized structures within a eukaryotic cell that perform distinct functions.
nucleus
The control center of the eukaryotic cell, housing DNA and regulating gene expression.
nuclear envelope
A double membrane that surrounds the nucleus, separating it from the cytoplasm.
nuclear pore
Protein-lined channels in the nuclear envelope that allow the transport of molecules between the nucleus and cytoplasm.
chromosomes
Thread-like structures of DNA and protein that contain genetic information.
endoplasmic reticulum
A network of membranes involved in protein and lipid synthesis; includes rough ER (with ribosomes) and smooth ER (without ribosomes).
lysosomes
Membrane-bound organelles that contain digestive enzymes to break down waste and cellular debris.
hydrolase
An enzyme that catalyzes the hydrolysis of a chemical bond.
mitochondria
The powerhouse of the cell, generating ATP through cellular respiration.
peptide bonds
Covalent bonds that link amino acids together in proteins.
N-terminus
The end of a polypeptide with a free amino group (-NH2).
C-terminus
The end of a polypeptide with a free carboxyl group (-COOH).
polypeptide
A chain of amino acids linked together by peptide bonds.
polypeptide backbone
The repeating sequence of atoms in a polypeptide chain, excluding the side chains.
disulfide bond
A strong covalent bond formed between sulfur atoms of two cysteine amino acids.
hydrogen bonds
Weak bonds between partially positive hydrogen and electronegative atoms (e.g., oxygen, nitrogen).
ionic bonds
Electrostatic attraction between oppositely charged ions in proteins.
Van der Waals forces
Weak interactions between molecules due to temporary dipoles.
secondary structure
Local folding patterns in a protein, including alpha helices and beta sheets.
tertiary structure
The overall 3D shape of a single polypeptide due to interactions between side chains.
protein domains
Distinct functional or structural units in a protein.
enzyme
A protein that speeds up biochemical reactions by lowering activation energy.
active site
The region on an enzyme where the substrate binds and a reaction occurs.
induced fit model
A model where an enzyme changes shape to better fit its substrate.
conformational change
A structural change in a protein that affects its function.
kinase
An enzyme that adds a phosphate group to a protein.
phosphatase
An enzyme that removes a phosphate group from a protein.
phosphorylation
The addition of a phosphate group to a molecule, often regulating protein activity.
purines
Double-ring nitrogenous bases (adenine, guanine) in nucleic acids.
pyrimidines
Single-ring nitrogenous bases (cytosine, thymine, uracil) in nucleic acids.
nucleotide
The building block of nucleic acids, consisting of a sugar, phosphate, and nitrogenous base.
dNTP
Deoxyribonucleotide triphosphates used as DNA building blocks during replication.
NTP
Nucleoside triphosphates used in RNA synthesis.
phosphodiester bond
The bond linking nucleotides in a DNA or RNA strand.
5’
The end of a nucleic acid strand with a phosphate group on the 5’ carbon of the sugar.
3’
The end of a nucleic acid strand with a hydroxyl group on the 3’ carbon of the sugar.
