USC Bridge 2.2 plasma membrane

Helpfulness: 0
Set Details Share
created 2 years ago by Ljporter
123 views
updated 2 years ago by Ljporter
show moreless
Page to share:
Embed this setcancel
COPY
code changes based on your size selection
Size:
X
Show:
1
card image

Plasma membrane

Selectively permeable- has a hydrophobic bilayer- allows hydrophobic molecules and small molecules like O2 can sneak between the membrane. Large hydrophilic molecules cannot pass through the membrane ie: glucose, sodium ions, hydrogen ions.

Separates interior and exterior of the cell

called cell membrane because it is the outermost coating of the cell

2
card image

Phospholipids

Forms the basic fabric of the membrane. Constructed of phospholipids which have a polar head that is charged and hydrophilic, they lie on the inner and outer surface of the membrane. It also has a uncharged nonpolar tail that is hydrophobic which lines up the center of the membrane.

maintains its spherical shape

allows them to reseal when torn

3
card image

Membrane proteins

Allow cell communication with the environment

Proteins make up about half of the mass of plasma membrane

have specialized membrane functions

two types: integral proteins and peripheral proteins

4

Integral proteins

Firmly inserted into the lipid bilayer, some protrude from one membrane face only, but most are transmembrane proteins that span the entire width of the membrane and protrude on both sides

5

Peripheral proteins

Not imbedded in the lipid layer, loosely attached inside or outside on integral proteins and are easily removed without disturbing the membrane.

some peripheral proteins are called enzymes others are motor proteins.

6
card image

6 membrane protein tasks:

  1. Transportation
  2. receptors for signal transduction
  3. attachment to the cytoskeleton and extracellular matrix
  4. enzyme activity
  5. intercellular joining
  6. cell cell recognition
7

Transport proteins

Protein on the membrane that provide a channel for certain molecules to enter the cell

8

Receptor molecules

Bond to signal molecules and can then emit second messengers which trigger changes inside a cell

Receptors are thus important links in the system of communication among cells

some signal molecules such as hormones are also proteins

9

Structural proteins

Shape and anchor cells, serve as tracks along who cell parts can move.

Bind cells together making organized units such as muscles, ligaments, and the tendons that bind muscles to bones

silk of spiders and hair of mammals are structural proteins

10

Cell enzymes

A protein that changes the rate of a chemical reaction without changing into a different molecule in the process

promote and regulate all chemical reactions in cells

11
card image

Diffusion

Tendency of molecules or ions to move from an area where they are in higher concentration to an area where they are in lower concentration. Can also be described as molecules moving down their concentration gradient.

Diffusion is based on concentration, collision, molecular size, and if a molecule is a lipid soluble molecule

12

Passive process

No energy is required for substances to move across the plasma membrane

go across via diffusion or a channel.

13
card image

Facilitated Diffusion

Certain hydrophilic molecules are transported passively down their concentration gradient ie: glucose, amino acids, and ions

the transported substance either binds to protein carriers in the membrane, or moves through water filled protein channels.

14

Carrier-mediated facilitated diffusion

Substances bind to protein and carries it through

15

Channel-mediated facilitated diffusion

Smaller molecules move through water filled channels, selected based on size.

16
card image

Active process

Energy (ATP) is required to move substance across the plasma membrane

17

Active transport (Solute pumps)

Move solutes like ions (Na, K, Ca) against the concentration gradient. Requires cells to expend energy (ATP).

two types: primary and secondary active transport

18

Vesicular transport

Large particles are transported through the cellular membrane in sacs or vesicles

19
card image

Cellular ATP energy

Chemical energy released when glucose is broken down is captured in ATP

ATP directly powers chemical reactions in cells and offers immediate usable energy needed by body cells

structure of ATP- adenine- containing RNA nucleotide with two additional phosphate groups

20

Structure of ATP

card image
21
card image

Uses of ATP in cells for transport

22
card image

Primary active transport

Required energy come directly from ATP hydrolysis

23
card image

Secondary active transport

Required energy is obtained indirectly from ionic gradients created by primary active transport

24

Phospholipids orient themselves in aqueous solutions such that:

The polar heads face the interior and exterior of the cell with the tails forming the center of the membrane

25

When movement of Na ions down their concentration gradient drives the transport of other substances across the membrane it's called:

Secondary active transport


Related pages


define fastidious bacteriabicarbonate buffer system equationhuman anatomy and physiology marieb 6th edition pdforder of draw for capillary puncturenaming of musclesorgan producing salivary amylaseaberration to kill a mockingbirdanatomy eye quizpearson essentials of human anatomy and physiologysentence using abrogatespinal cord and spinal nerves exercise 15 answerspericardial sac is lined withwhen acetic acid reacts with ammonia nh3 the reaction yieldswhat is a myofiberfriedrich monk by the sea analysisis color blindness recessive or dominantsolid ball of embryonic cellsnursing quiz questionssiamang taxonomywhat happens at destructive plate boundariesthe primary function of carbohydrates is toprimary gustatory cortex locationgray matter hornsnh4clo3cns and pns diagramhaemophilus ducreyi symptomssouthern comfort and amarettocodon codewhat are the functions of the uretersvenipuncture order of draw tubeschapter 6 anatomy and physiology quizletchapter 14 mastering biologyabbreviation for yardsoxford vocabulary level gclimate graph of tropical rainforestintrinsic muscles of the eyequantity theory of inflationdirect formation of the mitotic spindledo animal cells have cytoskeletongregor mendel performed his experiments withanatomical homologies exampleswhat are the mrna codons for phenylalaninethe pelvic brimwhat are the three main parts of the axial skeletontissues definition anatomyphosphodiester bond dnawhere does peristalsis occurmedical terminology suffixesprime mover define3 phosphoglyceratedescribe the process of ossification of the skullwhat is the name of the covalent compound ccl4capillary order of drawwhat is the function of the left bronchusmedial rotation of shoulder jointwhat is the function of vestibulelymphatic system functions and organsbutterfly needle to draw bloodfemur labeledabsence of ventricular electrical activityfundamentals of nursing volume 1the catcher in the rye study guide questionsfunction of sclerenchyma cellswhat organs are in the left iliac regionwhat type of bonds hold base pairs togetherwhy do birds excrete uric acidclass agnatha examplesmastering bioogybranch of left coronary arterydescribe the lytic cycle of virus reproductionosmosis requires atpclub mosses characteristicsstarfish excretory systemconnects the middle ear to the nasopharynxwhat blood vessel carries blood to the hearthesi a2 anatomy and physiology practicewhich of the following pairs are mismatchedthick ventricle wallsheart diagram with valvesis dna recombinant a virus or bacteria