Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Cells to systems > Lecture 8 > Flashcards

Lecture 8 Flashcards

1
Q

what method was use to move fluid and solutes from interstitial fluid into cells

A
  • Diffusion
  • facilitated diffsion
  • active
  • Co-transport
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What move the fluid and solutes from blood to interstitial fluid

A

Bulk flow and Starling’ Forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the different structures in the Plasma membrae

A 
v Phospholipid bilayer
v Proteins
- Integral {full or partial) &
surface or peripheral
v Cholesterol
v Carbohydrates linked to
proteins & lipids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the fluid mosaic model

A

v Noncovalent assemblies
v Lipids & proteins move
around within the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Are the internal and external layer similar

A

no, they are asymmetric

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the movements for lipids

A
  1. Lateral diffusion
  2. Rotation
  3. Swing
  4. Flexion
  5. Transverse diffusion (flip flop)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where are the position of Phospholipids

A
  • Choline (external)
  • Ethanolamine (internal)
  • Serine (internal)
  • Inositol (signalling)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where are the position of sphingolipids

A

Sphingomyelin (external)
• Glycosphingolipids
• Associate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the role of cholesterol

A

determines
fluidity and permeability
• Within membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the membrane lipid made up of

A
  • Phospholipids
  • sphingolipids
  • cholesterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How does the membrane lipid tail length affect fluidity

A

Fluidity decrease with length due to increased van der waal interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does the degree of unsaturation of fatty acids affect the membrane fluidity

A

It increases fluidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does cholesterol affect membrane fluidity

A

reduce fluidity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How does hydrophobic diffuse

A

Concentration gradient within membrane is greater, Diffuses quickly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How does hydrophilic diffuse

A

Hydrophilic (polar) substances in membrane are sparingly soluble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 4 types of molecules that may permeate through the membrane

A
  1. Non polar molecules
  2. Small uncharged polar molecules
  3. Large polar molecules & ions
  4. Macromolecules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Does Non polar molecules pass through membrane

A

Pass freely e.g. fatty acids, steroid hormones, CO2, & O2 (acts as
non polar - linear)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Does small uncharged polar moleccules pass through the membrane

A

Pass freely but more slowly than non polar molecules e.g. H2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Does large polar molecules & ions pass through properly

A

Don’t pass freely eg glucose, Na+ K+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Does macromolecules pass through the membrane

A

Don’t pass e.g. Proteins , polysaccharides, nucleic acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are some molecules cross the cell membrane in their non-charged form but not in their charged form

A
  • base (eg ammonia =NH3)

- acid (eg formic acid = HCOOH)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What determine whether the substance is charged or not

A

pH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Are the integral membrane protein permanently attached to the membrane?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the types of integral membrane protein

A 
1. Span entire membrane
• once or multiple times
• many a helices
• Examples –voltage gated ion channels ,
hormone receptors eg insulin
2. Integral monotopic proteins
• Examples enzymes -monoamine oxidase
• Do not span the entire biological
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How does Peripherally associated membrane | proteins attach to integral protein
often non-covalently bound
26
What are the functions of membrane protein
``` • Transport v Hydrophilic channel v ATP-pump • Enzyme functions v Active site exposed • Signal transduction v Receptors for external signals • Cell recognition v Molecules recognised by other cells proteins • Control adhesion v between cells and extracellular matrix • Cytoskeletal attachment v Microfilaments ```
27
How does simple diffusion function
``` • Down a concentration or electrical gradient v Through membrane v Through pores – integral cell membrane channel eg aquaporin for water v Through protein channels – selectively permeable, may be gated, eg ion channels ```
28
How does facilitated diffusion function
• Down a concentration or electrical gradient v Carrier mediated - need integral membrane protein v Transporter is specific for the molecule v Rate limited by binding and conformational change in carrier protein; eg glucose, amino acids
29
How does active transport function
• Up a concentration or electrical gradient | v Carrier mediated and energy dependent
30
What are the type of simple diffusion
• open or closed • "gated". • Rate of movement is limited by the rate of diffusion
31
Types of gated ion channels
``` • voltage-gated, e.g. Na+ or K+ (specific channel for each) • Chemical or ligand-gated, e.g. acetylcholine • mechanically-gated, e.g. sound waves in inner ear open ion channels ```
32
What are the Ion movement via transport protein affected by
1. Concentration gradient | 2. Electrical gradient
33
What is the nernst equation
Ex= Equilibrium Potential for x (or electromotive force preventing further diffusion) • Value is the membrane voltage for ion to be in equilibrium • = (61mV/charge) x log10 (internal concentration/external concentration)
34
What is the nerve cell transmission activated by
• Electrical stimulation (action potential) • Chemical stimulation (neurotransmitter) eg acetylcholine
35
What is Epilepsy and tinnitus
Overly excited nerves Voltage-gated K channels usually open to regulate nerve signals Remain closed in epilepsy and tinnit
36
What is • Hyperkalemic Periodic Paralysis in horses (muscle weaknes
Genetic defect in voltage-gated Na channels of muscle cells Channels remain open Results in muscle weakness and co
37
Where are the ion channels gated at
Some ion channels are gated by extracellular ligands; some by intracellular ligands.
38
What are some external ligands
1. Acetylcholine (ACh) n 2. Gamma amino butyric acid
39
What is Gamma amino butyric acid
``` BA) Binding at certain synapses in the central nervous system Admits Cl- ions into the cell Inhibits the creation of a nerve ```
40
What is Acetylcholine (ACh) ion channel
``` • Ionotropic receptor Nicotinic Ach receptor Opens Na+ ion channel Depolarization • Metabotropic receptor Muscarinic receptor Opens K+ ion channel Hyperpolari ```
41
What is Gamma amino butyric acid
``` BA) Binding at certain synapses in the central nervous system Admits Cl- ions into the cell Inhibits the creation of a nerve ```
42
What are the traits of ion channels
1. Traverse the membrane 2. Ion selective 3. Gated
43
What are the Different mechanisms for | activating the ion gates
1. Voltage-gated 2. Ligand-gated 3. Intracellular messengers-gated 4. Mechanically-gated • Stretch • Sound waves
44
What does pump protein do
against concentration/electrical gradients
45
What does gate channels do
with concentration/electrical gradients
46
What are symporters
• Na+ ions flow down their concentration gradient • Glucose co-binds with Na – transported up the glucose concentration gradient. (In most cells: glucose also goes down its concentration gradient and uses a simple uniporter)
47
What are antiporters
• Substances are transported in opposite directions • Electrochemical gradient for Na+ drives H+ or Ca++ in in the opposite directio
48
What is a uniporter
only a single ion is transported at a time
49
what is a example of symporter
(Na /amino acids+)
50
What is an example of an antiporter
( Na+/ H+ )
51
What are the secondary "active" trnsport
symporter and antiporter
52
Simple diffusion - membrane
H2O O2 CO2*
53
Simple diffusion - pore
H2O | aquaporin
54
Where does active transport happen along the epithelial sheet?
one side of the cell
55
Where does simple or facilitated diffusion happen along the epithelial sheets?
On other side of the active transport side
56
What is the function of pinocytosis
``` • Large molecules and particles require specialised processes to cross the plasma membrane - endocytosis • Molecules and particles are engulfed into intra-cytoplasmic vesicles • Endocytosis requires energy ```
57
Does endocytosis require energy
yes
58
What are the three types of endocytosis
1 Non-receptor mediated pinocytosis 2 Receptor mediated endocytosis 3 Phagocytosis
59
Non-receptor mediated pinocytosis
``` Continuous nonspecific uptake of extracellular fluid and small dissolved molecules 1. Vesicle buds off from plasma membrane 2. Vesicle transported intact, releasing contents to exterior by exocytosis or fuses with a lysosome 3. Membrane components recycled to the plasma membrane ```
60
Receptor mediated | endocytosis
``` vVia clathrin–coated pits in epithelial and phagocytic cell membranes • Pits contain integral protein receptors for molecules being endocytosed vVia caveolin-coated pits (Caveolae) in cell membranes of vascular endothelial cells and adipocytes • Transport of albumin • Folate receptor ```
61
Phagocytosis
``` • Endocytosis of large particulate matter such as microorganisms or cell debris • Receptor-mediated • Carried out by specialised phagocytic cells • Immune-related 1. Microbe recognised by receptor 2. Phagosome forms 3. Phagosome fuses with lysosome (phagolysosome) 4. Microbes killed by proteolytic enzymes, reactive oxygen species (ROS) and nitric oxide (NO) ```

Cells to systems (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions