null
US
Iniciar Sesión
Regístrate Gratis
Registro
Hemos detectado que no tienes habilitado Javascript en tu navegador. La naturaleza dinámica de nuestro sitio requiere que Javascript esté habilitado para un funcionamiento adecuado. Por favor lee nuestros
términos y condiciones
para más información.
Siguiente
Copiar y Editar
¡Debes iniciar sesión para completar esta acción!
Regístrate gratis
3947593
Cell Membrane
Descripción
components and functionality of a cell membrane
Sin etiquetas
cell membrane
biology
biochemistry
biology
4ui
Mapa Mental por
Julia Castellani
, actualizado hace más de 1 año
Más
Menos
Creado por
Julia Castellani
hace casi 9 años
77
1
0
Resumen del Recurso
Cell Membrane
Functions
Separates cytoplasm from environment
controls the traffic of molecules(**selectively permeable**)
recognized by other cells, hormones, and antibodies
Membrane Lipids
Phospholipids
Nota:
most abundant lipids in membrane
amphipathic (hydrophobic & hydrophillic regions)
Functions: -form layers on surface of water -determine fluidity at lower temps (varying degrees of unsaturation in tails)
Glycolipids
Nota:
like phospholipids, but with sugars attached at head
Found only on outside layer of plasma membrane
Functions: -protect cell surface -act as recognition sites -help cells stick to surfaces
Cholesterol
Nota:
small, flat, ringed steroid between phospholipid molecules
Functions: -decrease membrane fluidity -decrease membrane permeability -make membranes tougher
Membrane Proteins
Functions
Enzymes
Transport
Receptors
Formation of Junctions
Cell-Cell Recognition
Attachment to extracellular matrix
Properties
Amphipathic
move around in membrane
some protrude on both sides of membrane
Eg) Globular Proteins ('Potato"), Glycoprotein
Membrane Transport
Passive Trasport
Simple Diffusion (high-low concentration)
Non-polar solutes
Nota:
cross easily (eg oxygen, hydrocarbons)
smaller molecules cross faster
Polar solutes
Nota:
small ones (eg Carbon Dioxide, Water) cross easily
larger molecules (eg sugars) won't pass readily
Ions pass hardly at all
Facilitated Diffusion (high-low concentration of solute)
Nota:
polar solutes and ions are helped by transport proteins
solute is moving across a membrane from high-low concentration
carrier proteins
Nota:
bind to a solute and physically move them across membranes
very specific
channel proteins
Nota:
provide a hydrophilic channel for ions
less specific
Active Transport
Nota:
molecules move against concentration gradient (low-high)
Requires transport protein and energy input (eg Sodium / Potassium pump)
Eg) Sodium-Potassium pump
Nota:
-found in plasma membrane
same carrier transports sodium and potassium ions across membrane in opposite directions
3 sodium ions out for every 2 potassium ions in
pump is "electrogenic" (produces a change in electrical charge) because it creates a membrane potential
uses ATP as energy
Molecules move against concentration gradient
requires transport proteins and energy
Co-Transport Systems
Ion pump works together with another protein transporter
Nota:
Eg) glucose pump
Regulated Transport
Nota:
can be PASSIVE or ACTIVE
involves the movement of molecules through specialized channels
Voltage Gated Channels
Nota:
-closed when electric potential is high (polarized) -open when potential is low (depolarized)
Ligand Gated Channels
Nota:
-closed when concentration of molecule is low -open when concentration is high
Transport of Large Molecules
Endocytosis
Phagocytosis (uptake of solids)
Pinocytosis (uptake of fluids)
Receptor-mediated endocytosis (specific uptake of proteins)
Exocytosis
reverse of endocytosis
Mostrar resumen completo
Ocultar resumen completo
¿Quieres crear tus propios
Mapas Mentales
gratis
con GoConqr?
Más información
.
Similar
Carbohydrates
kevinlinkovoor
DNA Basics
Sarah Juliette B
DNA questions not from the lectures
MrSujg
Protein section 1
MrSujg
Protein section 5
MrSujg
Protein section 3
MrSujg
Protein section 2
MrSujg
Biology AQA 3.1.3 Cells
evie.daines
Biology AQA 3.2.5 Mitosis
evie.daines
Biology AQA 3.1.3 Osmosis and Diffusion
evie.daines
Biology- Genes, Chromosomes and DNA
Laura Perry
Explorar la Librería