What a cell is
1.[2p] Why does Pasteur's swan-necked flask experiment support the claim that cells arise only from cells?
Why does Pasteur's swan-necked flask experiment support the claim that cells arise only from cells?
The answer is: Sterile broth open to the air stayed sterile while dust was trapped in the neck, and clouded only when the broth was tipped to touch the dust
The answer is: Sterile broth open to the air stayed sterile while dust was trapped in the neck, and clouded only when the broth was tipped to touch the dust
The answer is: Sterile broth open to the air stayed sterile while dust was trapped in the neck, and clouded only when the broth was tipped to touch the dust
2.[1p] Hooke's 1665 observations of cork showed living cells.
Hooke's 1665 observations of cork showed living cells.
The answer is: False
3.[2p] Using with m²/s, how many seconds does a small molecule take to diffuse 100 µm?
Using with m²/s, how many seconds does a small molecule take to diffuse 100 µm?
4.[2p] A cell of radius 1 µm and a cell of radius 10 µm are compared. What happens to the membrane area available per unit of cell contents?
A cell of radius 1 µm and a cell of radius 10 µm are compared. What happens to the membrane area available per unit of cell contents?
The answer is: It falls by a factor of ten, since the ratio of surface to volume is
The answer is: It falls by a factor of ten, since the ratio of surface to volume is
The answer is: It falls by a factor of ten, since the ratio of surface to volume is
5.[3p] Match each quantity for one Escherichia coli cell to its approximate value.
Match each quantity for one Escherichia coli cell to its approximate value.
Cell volume
Protein molecules
Genome size
Length of its DNA
Protein concentration in the cytoplasm
1.6 mm
200 g per litre
1 µm³
3 million
4.6 million base pairs
Show the answer
Cell volume: 1 µm³ Protein molecules: 3 million Genome size: 4.6 million base pairs Length of its DNA: 1.6 mm Protein concentration in the cytoplasm: 200 g per litre
6.[2p] Which of these are found in bacteria, archaea and eukaryotes alike?
Which of these are found in bacteria, archaea and eukaryotes alike?
Select all that apply
The answer is: A lipid bilayer boundary, A double-stranded DNA genome, Ribosomes built partly of RNA
The answer is: A lipid bilayer boundary, A double-stranded DNA genome, Ribosomes built partly of RNA
7.[2p] Put these in order of increasing size.
Put these in order of increasing size.
A skeletal muscle fibre
A bacterium such as E. coli
A typical human cell
A ribosome
Show the answer
a, b, c, d
8.[2p] Which group did Woese separate from the bacteria in 1977 using ribosomal RNA?
Which group did Woese separate from the bacteria in 1977 using ribosomal RNA?
9.[2p] What is the honest reason a mature human red blood cell sits awkwardly with the cell theory?
What is the honest reason a mature human red blood cell sits awkwardly with the cell theory?
The answer is: It has ejected its nucleus, so it cannot divide and cannot give rise to another cell
The answer is: It has ejected its nucleus, so it cannot divide and cannot give rise to another cell
The answer is: It has ejected its nucleus, so it cannot divide and cannot give rise to another cell