Principles of Cell + Membrane Function

 
Site for metabolism (biochemistry)( and protein
synthesis. It has " " (i.e. glycogen storgae vessels)

 
House the genetic information in the form of DNA
carrying instructions for bodily functions (22
autosomes, 2 sex chromosomes), RNA synthesis

 
ATP synthesis and calcium storage

 
ER Lipid synthesis

 
Translation of mRNA

 
Translation of mRNA

 
Intracellular degradation

 
Sorting, packaging of proteins and lipids for delivery

 
Cellular uptake

 
Degradation of intracellular proteins

 
Detoxification of substances

Plasma membrane
Creates  gradient, cell communication via   +  

****TEST QUESTION
 : network of protein fibers that
supports the cell structure and functions
(organelle movement, cell division and trafficking)

What are the 3 cytoskeleton components?
 ,  , 

What intermediate is in epithelium?

What intermediate is found in Connective tissue (fibroblasts,
endothelial cells, chondroblasts and
mesenchymal cells)?

What intermediate is found in Neuroglial (glial cells, astrocytes,
Schoeman cells and oligodendrocytes)?

In what cell type are neurons found (axons, dendrites, and neuronal appendages)?

Diameter of microfilaments? Protein subunit?

Diameter of intermediate filament? Protein subunit?

Diameter of microtubule? Protein subunit?

TQ The nucleus houses the instructional information for homeostatic process in the form of  

TQ The nucleus site of gene regulation,   and  , where all machinery
reside

TQ The nucleus is encapsulated by a   (  membrane)

TQ The nucleus outer layer of nuclear envelop is continuous with  
and contains 

TQ The nuclear pores are associated with  , which allow the
passage of substance between nucleus and cytoplasm

TQ Only proteins with   are allowed in the nucleus

TQ Only proteins with   are allowed to exit the nucleus

TQ The inner membrane is supported by  .
Intermediate filament types  

TQ DNA complexed with histones is called  . Malignant cells contain more  

TQ Inclusion bodies called   synthesize cells rRNA

TQ
RER plays a role in   (contains  )

TQ Smooth ER is responsible for
 ,  
and  ,   for muscle contraction
and  

 
Site for metabolism (biochemistry)( and protein
synthesis. It has " " (i.e. glycogen storgae vessels)

  pathwya: Secretion is continuous and unregulated

 : Secretion is directed by hormonal or neural signal

Golgi apparatus is divided into
receiving end of packaged
protein from RER ( -Golgi),
modifying Golgi where protein
modifications occur (Golgi stack)
and exporting Golgi, where
modified proteins are packaged
and sent to their destination
( -Golgi)

Proteins need a tag (localization signal)to reach their destination (i.e.
 is the tag associated with proteins destined for the
lysosome)

Proteins without a tag become  

A   (mannose-6-phosphate) targets new hydrolytic
enzymes to lysosomes- defects in the process leads to fatal childhood
lysosomal storage disease

Lysosomes are made in the   as coated vesicles

  Disease a lysosomal enzyme is missing and causing cells to
accumulate compounds ( ). Accumulated material within neurons
interferes with function. It is a   disease.

TQ Mitochondria have their own   and have a   membrane

TQ  affect important systems in the body, nervous and muscles.

TQ
The outer membrane transports   into the mitochondria
The inner membrane forms  , called a  , allow a   for reactions

TQ Mitochondria is the primary site of   (contains many enzymes for B-oxidation of fatty acid,  production,  cycle and oxidative
phosphorylation ) and has the proteins of the  

TQ Cells requiring a lot of energy will have a lot of mitochondria per cell, most affected
in mitochondrial diseases. Development of   or   disease have been associated with higher mtDNA mutation rate

Plasma membrane lipid composition varies by cell type,
fluidity is determined by  and
 - important!

What are the 3 membrane proteins?

What are the three types of membrane proteins?

TQ
Phospholipids are the major lipid of plamsa membrane. Hydrophillic head of  , hydrophobic  .

Phospholipids create   create  

The  fatty acid in the phospholipid creates a “kink” in the chain,
which prevents tight packing –important for membrane fluidity

What are the two phospholipids on the outer leaflet?

What are the 3 phospholipids on the inner leaflet?

3 classes of sphingolipids are ,  , and  

TQ
Cholesterol is found in both leaflets and provides   to the lipid bilayer at normal body temp.

TQ
  of the lipids in the membrane can be cholesterol

Cholesterol aids in stifferning the membrane and can flip easily.   can move laterally, rotate, or flex. They rarely do  .

Glycolipids
-  component
-  group is a
carbohydrate

Glycolipids
-  are two fatty
acyl chain
-Important in cel-cell
interactions

Glycolipids
-  type
-Pathogen recognition
-  formation

Fluid Mosaic Model
A fluid like
 
bilayer where lipids
and proteins are
embedded

TEST QUESTION
Large uncharged  
molecules need
transporters

TQ
Ions need  

-Only  
molecules diffuse
through the PM
- To a lesser extent
  polar
molecules

3 examples of hydrophobic molecules that diffuse through the membrane

Homeostasis is achieved when
 =  

How does a sodium/potassum work?

Bilayer has TM proteins that are
active pumps to maintain
concentration gradients; e.g.  

Concentration gradient is  

NO ATP = NO  , you lose the
concentration gradient-cell dies

Proteins that are either  
into the bilayer or 
to the bilayer

The integrated proteins are
imbedded in the bilayer,
  amino acids are
associated with the hydrophobic
 

The non embedded integral
membrane proteins are anchored to
a   or   by a  

TEST QUESTION
2 examples of GPCR

TEST QUESTION
Example of ligand binding receptor

TEST QUESTION
Example Transport proteins i.e. pump, carrier,
pores and ion channels

TEST QUESTION
Example of Enzymes

TEST QUESTION
2 example of adhesion molecules

  are important in important in excitable
cells (neurons and
muscle cells)

Ion channels are classifed by their
 ,  
and mechanism of  

Majority of Ion channels
are  

Conductance is the property of the channel, how many ions are allowed through,
can vary based on   ( vs.  )

 channel, important in coupling
electrical signal to calcium release: neuronal excitability, muscle
contraction, etc. (high conductance and selective for potassium)

TEST QUESTION
The gate can be a  
(neurotransmitter/ or an
intercellular messenger),
  (such as
pressure or stretch),
  (membrane
potential)

In the cases when there is
no gate, the ion channel is
always in an  

Different types in different cells, the potassium channel all responsd to   effect
in the cell- ligand gated ( ,  ,  )

Stretch gated ions are sensed by the   i.e., stretch are translated into
  or  signals

Cell-matrix adhesion molecules: Integrins, allow
communication between a cell & its surrounding tissue
(adaptation). Critical for cell  ,  
cellular   & 

What are two examples of cell-to-cell communication?

Cadherins:   cell adhesion
molecules; e.g.,  

N-CAMs:  neural cell adhesion
molecules are part of the immunoglobulin family
& function in the migration of  s &
development of 

GPI-linked class: function is  

Loss of cell adhesion molecules is observed in  tumors

Peripheral membrane proteions are  in the membrane
and  bound. They are loosely attached to the
membrane on either side by
 

 is a classical
example, anchors the
cytoskeleton of red blood
cells to an integral meme
bane protein

Ankyrin is loosely bound to the plasma
membrane by the integral membrane protein
( ) and holds or “anchors”  
network to Band 3

Plasma membrane receptors include
1. Ligand gated ion ( )
2. Receptor kinases ( )
3. G protein coupled receptoprs ( ,  , and  )

Intracellular receotors include transcription factors ( )

  = targets same cell
  = ajacent cell
 = Bloodstream

Homeostasis is achieved when
 =