cell transport Flashcards
what are the main functions of cell membrane?
Compartmentalization, transport, enzyme activity, signal transduction, intercellular joining, cell recognition, and attachment to the extracellular matrix.
What is the structure of the cell membrane?
What is the structure of the cell membrane?
What is the Fluid Mosaic Model?
A model describing membranes where proteins float within the lipid bilayer, allowing for diverse functions.
How do transport proteins function?
Transport proteins allow specific molecules to pass through the membrane, either by channel or carrier proteins.
What is the sodium-potassium pump, and why is it important?
The pump moves Na⁺ out and K⁺ into the cell, creating an electrochemical gradient essential for cell function
What are the main types of membrane transport?
Passive (diffusion, facilitated diffusion) and active transport (requires ATP).
What is receptor-mediated endocytosis?
A process where cells take in specific molecules by forming vesicles around them.
How do proteins move within cells?
Through gated transport, transmembrane transport, and vesicular transport, often guided by signal sequences.
how are membranes electrically charged?
ions will travel in and out of cells to try and balance this charge causing a gradient of charge or an electrochemical gradient
What role do motor proteins play in transport?
Motor proteins like myosin, kinesin, and dynein move cargo along microfilaments and microtubules using ATP.
What is the function of the nuclear pore complex (NPC)?
NPCs transport proteins in and out of the nucleus, recognizing signals and moving 500 molecules per second.
what are transport proteins and give example of some and their function?
transport proteins allow passage of hydrophobic substances across the membrane
channel proteins called aquaporins facilitate the passage of water. other transport proteins called carrier proteins bind to molecules and change shape to allow them across
how does the cell know where to send proteins?
post- translational modification of proteins
glycosylation targets proteins to plasma membrane
phosphorylation can alter protein-protein interactions leading to redistribution to other compartments
ubiquitination sends proteins for breakdown in the proteasome
