Protein Folding and Bonds
These bonds connect amino acids together in a polypeptide chain.
What are peptide bonds?
These are the basic structural and functional units of all known living organisms.
What are cells?
This class of lipids forms the bilayer structure of cellular membranes.
What are phospholipids?
This process moves small, nonpolar molecules like oxygen and carbon dioxide across the lipid bilayer without the use of energy.
What is passive diffusion?
This type of protein is found in the nucleus and binds to DNA, helping to regulate gene expression, while this type of protein is found in the cytoplasm and is involved in protein synthesis.
What are transcription factors and ribosomes?
These weak interactions, including hydrogen bonds, ionic bonds, van der Waals forces, and hydrophobic interactions, play a crucial role in stabilizing a protein's folded structure.
What are non-covalent interactions?
The minimum requirements for life include ribosomes, a membrane, genetic material, and this fluid matrix.
What is cytosol/cytoplasm?
This steroid is a lipid that stabilizes the fluidity of the plasma membrane, especially in animal cells.
What is cholesterol?
This type of membrane transport requires the use of a protein channel but does not require energy, moving substances down their concentration gradient.
What is facilitated diffusion?
These two types of cytoskeletal filaments provide structural support and contribute to cell movement, but one is more flexible and made of protein subunits like keratin, while the other is rigid, hollow, and made of tubulin.
What are intermediate filaments and microtubules?
This is the protein structure level determined solely by the sequence of peptide bonds and amino acid residues.
What is the primary structure?
This is the cellular structure responsible for synthesizing proteins.
What are ribosomes?
This term describes lipids that have both hydrophilic and hydrophobic regions, making them essential for membrane formation.
What is amphipathic?
Transporters like the sodium-potassium pump use this type of energy to move substances against their concentration gradient.
What is ATP?
These two cell cycle regulators work together, but one is a protein whose levels fluctuate during the cycle and activates the other, which is an enzyme that drives the cell cycle forward by phosphorylating target proteins.
What are cyclins and cyclin-dependent kinases (CDKs)?
Protein folding is driven by this effect, where non-polar amino acids are buried in the protein's interior to avoid water.
What is the hydrophobic effect?
This fibrous protein provides tensile strength to the extracellular matrix and is abundant in connective tissues like tendons and skin.
What is collagen?
These proteins are embedded within the lipid bilayer and can act as channels or transporters for molecules.
What are integral membrane proteins?
Unlike channels, which allow rapid movement of molecules across the membrane, transporters tend to be slower because they require this action to move molecules.
What is a conformational change?
This enzyme adds phosphate groups to proteins, typically activating or altering their function, while this enzyme removes phosphate groups, often reversing the effects of phosphorylation.
What are kinases and phosphatases?
These covalent bonds form between cysteine residues to stabilize the tertiary or quaternary structure of a protein.
What are disulfide bridges?
This cellular process prevents overproduction by inhibiting pathway enzymes once enough product has been made.
What is feedback inhibition?
Phospholipids in the membrane can move laterally or rotate, but rarely perform this type of movement between layers.
What is flip-flop (transverse diffusion)?
This type of transport can occur through either a channel or a transporter, but is characterized by the movement of substances down their concentration gradient, without using energy.
What is facilitated diffusion?
These two types of mutations can affect genes, but one involves a change in a single nucleotide, while the other involves the addition or deletion of nucleotides.
What are point mutations and frameshift mutations?