The Cell Membrane Structure

Question 1

Gateway of the cell that acts as a boundary, controls what enters and leaves, regulates chemical composition, and maintains homeostasis of the cells

Answer 1

Cell Membrane

Question 2

Most commonly studied organism for cell membrane

Answer 2

Erythrocytes

Question 3

Flexible and allows a unicellular organisms to perform locomotion

Answer 3

Cell Membrane

Question 4

A model that suggests that the plasma membrane is made of two layers of globular proteins with phospholipid inside to make a layer and then join two layers together to make a channel for molecules to pass

Answer 4

Sandwich Model

Question 5

Who were the proponents of the Sandwich Model

Answer 5

Danielli and Davson

Question 6

Model that suggests the plasma membrane has an outer layer of glycoprotein coat with phospholipid bilayer inside. Proposed by Robertson

Answer 6

Unit membrane model

Question 7

Model that suggest the phospholipid bilayer are composed with proteins partially or fully imbedded. The basic paradigm of biological membrane structure proposed by Singer and Nicolson

Answer 7

Fluid-Mosaic Model

Question 8

The lipids in a membrane are organized into a __________________________

Answer 8

Liquid crystalline lattice

Question 9

The transition temperature of the lipid membrane

Answer 9

-20 degrees celsius to 60 degrees celsius

Question 10

How many types of protein are present in the cell membrane?

Answer 10

50 different types of protein

Question 11

Trait of the lipid molecules to having a hydrophilic and a hydrophobic end

Answer 11

Amphipathic or Amphiphilic

Question 12

Process of rapidly freezing membrane followed by a fractionation using a knife

Answer 12

Freeze-Fracture

Question 13

Why is the plasma membrane composed of two layers of lipids?

Answer 13

To repel the water that constantly surrounds the cell. To much water can cause the cell to burst

Question 14

Describes that the plasma membrane has consistency of olive oil at body temperature due to unsaturated phospholipids.

Answer 14

Fluid

Question 15

Characteristic of the plasma membrane where proteins form a collage that differs on either side of membrane and from cell to cell (greater than 50 types of proteins)

Answer 15

Mosaic

Question 16

State of hydrocarbons when exposed to low temperatures:

Answer 16

Gel phase

Question 17

Hydrocarbon phase at high temperatures

Answer 17

Fluid phase

Question 18

Formation of _________ is energetically favorable

Answer 18

Sphere

Question 19

______ a harsh ionic detergent, and ________, a gentler non-ionic detergent commonly used as solubilizing agents

Answer 19

SDS, Triton X100

Question 20

Types of phospholipid membrane movement

Answer 20

1. Lateral Diffusion
2. Flexion
3. Rotation
4. Flip-flop(rare)

Question 21

It affects the fluidity of the plasma membrane

Answer 21

Cholesterol

Question 22

Found in plants and serves the same purpose as cholesterol in the plasma membrane

Answer 22

Sterol

Question 23

How does cholesterol affect fluidity at body temperature?

Answer 23

Lessens fluidity

Restrains the movement of phospholipids, also reducing permeability

Question 24

Cholesterol maintains fluidity by not allowing phospholipids to pack close together during

Answer 24

Colder temperatures

Question 25

__________ of the cholesterol makes the plasma membrane more rigid, less permeable, and resistant to low temperature crystalization

Answer 25

Planar rings

Question 26

Major membrane component in animal cells. Not found on plant cells. Sterols function the same.

Answer 26

Cholesterol

Question 27

Solid state of the plasma membrane

Answer 27

Paracrystalline state

Question 28

Classification of Membrane Proteins

Answer 28

1. Peripheral Membrane Proteins 2. Integral Membrane Proteins 3. Transmembrane Proteins

Question 29

Types of Membrane Proteins

Answer 29

1. Channel Protein 2. Carrier Protein 3. Cell Recognition Protein 4. Receptor Protein 5. Enzymatic Protein

Question 30

Channel and Carrier proteins belong to this classification of membrane proteins

Answer 30

Transport Proteins

Question 31

Protein for insoluble molecules and ions to pass through freely

Answer 31

Channel Proteins

Question 32

Binds to a substance/solute and carry it across the membranes, conforms to the shape of the substance in process

Answer 32

Carrier Proteins

Question 33

Binds to chemical messengers which sends a signal to the cell, causing cellular reaction

Answer 33

Receptor Protein

Question 34

Carries out enzymatic reactions at the membrane when a substrate binds to it

Answer 34

Enzymatic Proteins

Question 35

Serves as ID tags of the cell, made from glycoproteins

Answer 35

Cell recognition proteins

Question 36

Maintains cell shape and stabilize by attaching to the cytoskeleton or the extracellular matrix

Answer 36

Attachment Proteins

Question 37

Space between the cells composed and filled with proteins and carbohydrates secreted by the cells in return supports the cells in a tissue

Answer 37

Extracellular Matrix

Question 38

Binds the cells together, two types: Tight and Gap junctions

Answer 38

Intercellular Junction Proteins

Question 39

Type of cell junction where transmembrane proteins of opposite cells attach in a zipper like fashion | No leakage

Answer 39

Tight junctions | Bars the movement of dissolved materials

Question 40

Cytoplasmic plaques of two cells bind with the aid of intermediate filaments of keratin | Allows for stretching ## Footnote Ex. Bladder, Stomach, Heart

Answer 40

Desmosomes

Question 41

Channel of opposing cells join together creating small channels for ions, sugars, amino acids, and other small molecules to pass | Allows direct communication between cells

Answer 41

Gap Junctions

Question 42

A type of gap junction present on plant cells

Answer 42

Plasmodesmata

Question 43

Establishes the rate of Membrane Component Movement

Answer 43

Fluorescence Recovery After Photobleaching (FRAP)

Question 44

The lattice becomes a _________ at transition temperature

Answer 44

Frozen crystalline gel