Cell Theory

Question 1

What are the three principles of cell theory?

Answer 1

• All living cells come from pre-existing cells
• The cell is the basic unit of life
• All living organisms are composed of cells

Question 2

Who was the first inspiration of cell theory?

Answer 2

Robert Hooke

Question 3

What did Robert Hooke observe under a microscope to then coin the term “cells”?

Answer 3

A cork

Question 4

Who else contributed to cell theory?

Answer 4

Schleiden and Schwann

Question 5

Do prokaryotes and eukaryotes both have a nucleus?

Answer 5

Nucleus is only present in eukaryotes. Prokaryotes have non membrane bound DNA

Question 6

Do prokaryotes and eukaryotes both have cell walls?

Answer 6

Usually only prokaryotes have a cell wall as well as a plasma membrane

Question 7

What is the general size of a prokaryote?

Answer 7

1-10µm

Question 8

What is the general size of an eukaryote?

Answer 8

10-100µm

Question 9

Examples of prokaryote

Answer 9

Archae, bacteria

Question 10

Examples of eukaryotes

Answer 10

Plants, animals

Question 11

What is a microelectrode?

Answer 11

An electrode of very small size, used in neurobiology. Traces electrical signals

Question 12

What is the principle behind the use of fluorescent dyes in cell biology?

Answer 12

Based on shining light of a specific wavelength on the sample which is then edited at a different wavelength and observed

Question 13

What two types can bacteria be split into?

Answer 13

Gram positive or gram negative

Question 14

What does it mean for a bacterium to be gram positive?

Answer 14

Thicker peptidoglycan layer which retains the crystal violet stain

Question 15

What does it mean for a bacterium to be gram negative?

Answer 15

Do not retain stain. Peptidoglycan layer lies between two membranes

Question 16

What disease is involved with a deficiency in scramblase?

Answer 16

Scott’s disease

Question 17

What kind of proteins are membrane transport proteins?

Answer 17

Multi-pass integral membrane protein

Question 18

What is uniport transport?

Answer 18

When a molecule is transported through a membrane via a carrier

Question 19

What is symport transport?

Answer 19

When a molecule is transported with a co-transported ion via carrier

Question 20

What is antiport transport?

Answer 20

When a molecule is transported through one way and an ion is co-transported the opposite way via carrier

Question 21

What gives an electrochemical gradient?

Answer 21

The combination of membrane potential and concentration gradient

Question 22

What 3 things help to maintain membrane asymmetry?

Answer 22

• Tight junctions
• Lipid rafts
• Flippase

Question 23

Give an example of how the lipid composition of each leaflet differs?

Answer 23

Phosphatidyl-serine is found in the cytosolic monolayer to help maintain negative potential across membrane

Question 24

Examples of proteins that carry out active transport

Answer 24

• Coupled carrier (symport/antiport transport
• ATP-driven pumps
• Light-driven pumps

Question 25

What is the cytoskeleton composed of?

Answer 25

- Thick filaments - Thin filaments - Intermediate filaments - Microtubules

Question 26

What is the thick filament in the cytoskeleton?

Answer 26

Myosin

Question 27

What is the thin filament in the cytoskeleton?

Answer 27

Actin

Question 28

G/F actin?

Answer 28

G-actin is a helical polymer and can form the trimer F- actin

Question 29

What are the microtubules in the cytoskeleton for?

Answer 29

Structural support and subcellular motility, especially in mitosis

Question 30

Where do the microtubules originate from?

Answer 30

Centrosome

Question 31

What are the intermediate filaments for?

Answer 31

Structural support

Question 32

Peripheral membrane proteins can form a __________ cytoskeleton

Answer 32

Submembranous/Cortical

Question 33

What is the "+" and "-" end found on filaments?

Answer 33

The plus end is the growing end where molecules are added | The minus end is the shrinking where where molecules leave

Question 34

What does the cortical cytoskeleton mainly consist of?

Answer 34

Spectrin

Question 35

Which cell is used as an example of a cell with a sub membranous cytoskeleton?

Answer 35

Erythrocyte

Question 36

What are the two forms of spectrin?

Answer 36

Alpa and beta

Question 37

What can spectrin form?

Answer 37

A dimer

Question 38

What do spectrin dimers bind to?

Answer 38

Protein band 4.1 and ankyrin

Question 39

What protein band does spectrin bind to?

Answer 39

4.1

Question 40

What does does protein band 4.1 bind to?

Answer 40

Actin

Question 41

What kind of meshwork is formed?

Answer 41

A spectrin-actin meshwork

Question 42

What is the spectrin-actin meshwork anchored by?

Answer 42

Ankyrin

Question 43

What kind of membrane protein is ankyrin?

Answer 43

Peripherally associated membrane protein (which is bound to integral membrane proteins)

Question 44

What does the cortical cytoskeleton provide?

Answer 44

Provides the plasma membrane with strength and resilience (also forms mechanical barriers to diffusion)

Question 45

What would happen if the cortical cytoskeleton didn't cause the plasma membrane to have a biconcave shape?

Answer 45

The erythrocytes would tear when going through capillaries

Question 46

What is your blood group determined by?

Answer 46

The structure of the oligosaccharides

Question 47

What does the structure of oligosaccharides determine?

Answer 47

Blood group

Question 48

Which blood group is the universal donor?

Answer 48

O

Question 49

Which blood group is the universal acceptor?

Answer 49

AB