This document provides a comprehensive look at membrane transport, detailing the mechanisms by which substances move across cell membranes, including passive and active transport processes.
[Mostrar más]
Última actualización de este documento: 5 meses hace
COMPLETE TEST BANK FOR Molecular Biology of the Cell (Seventh Edition) 7th Edition Kindle Edition by Bruce Alberts , Rebecca Heald Alexander Johnson || LATEST EDITION {2024 -2025}
TESTBANK FOR MOLECULAR BIOLOGY OF THE CELL 7TH EDITION/COMPLETE GUIDE 2024-2025
Samenvatting H2 en H3 Molecular Biology of the Cell (Seventh Edition) - Molecular Biology of the Cell 1 (WBFA006-04)
Todos para este libro de texto (14)
Escuela, estudio y materia
Aston University, Birmingham (Aston)
Desconocido
Cells To Systems (BB4CTS)
Todos documentos para esta materia (8)
Vendedor
Seguir
ame03
Vista previa del contenido
Cells To Systems - Membrane Transport
Membrane Transport
Permeability Of Membranes:
Small gases, oxygen, carbon dioxide, nitrogen, etc are freely permeable
to the membrane (they can travel across)
Hydrophobic Molecules - Because of their properties they are able to
penetrate and cross the membranes
Small polar molecules e.g. water can go through the membrane
to some extent, but this transport won’t be as efficient, although
water can go across the membrane
Water has special channels that facilitate diffusion of water across
the membrane
Large polar molecules/charged molecules e.g. ions/amino acids are really selective (does not let these
molecules pass through as the membrane will not let it happen)
Transmembrane Proteins Facilitate Transport:
For the molecules to cross the membrane, they go through transporters and channels
which provide specificity (selectivity), facilitating molecules inside
Define which substrates are allowed into the compartment
Channels - Only allows certain types of ions/substrates to cross
Solutes - Molecules passing from 1 membrane to another
Transporter/Carrier - Only allow specific small molecules to pass
Concentration Gradients:
Difference in concentration (a gradient) represents a chemical potential
There will be more of the If we remove this membrane, Process is unidirectional
solute/chemical on 1 side (C) these molecules will diffuse
and less on the other side (c) From high concentration to low
until the concentration of
concentration, cannot go the opposite
them becomes equal
= this difference/gradient way until it reaches equilibrium
provides a chemical potential
Potential Energy:
The concentration gradient of a substance across a membrane represents potential energy as it drives diffusion
e.g In this dam, there is a lot of concentration of water on 1 side and not a lot
on the other. However, if the barrier is removed, the force can diffuse/go
down = potential energy has been restored and released and can travel
e.g. When the bow is pulled back, there is potential
energy which is stored. When the string is released,
the potential energy is converted to kinetic energy
in movement of the arrow. The string pushes the
arrow out and is the driving force behind the motion
1
Los beneficios de comprar resúmenes en Stuvia estan en línea:
Garantiza la calidad de los comentarios
Compradores de Stuvia evaluaron más de 700.000 resúmenes. Así estas seguro que compras los mejores documentos!
Compra fácil y rápido
Puedes pagar rápidamente y en una vez con iDeal, tarjeta de crédito o con tu crédito de Stuvia. Sin tener que hacerte miembro.
Enfócate en lo más importante
Tus compañeros escriben los resúmenes. Por eso tienes la seguridad que tienes un resumen actual y confiable.
Así llegas a la conclusión rapidamente!
Preguntas frecuentes
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
100% de satisfacción garantizada: ¿Cómo funciona?
Nuestra garantía de satisfacción le asegura que siempre encontrará un documento de estudio a tu medida. Tu rellenas un formulario y nuestro equipo de atención al cliente se encarga del resto.
Who am I buying this summary from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller ame03. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy this summary for $7.58. You're not tied to anything after your purchase.