Life on Earth and Macromolecules

Question 1

What are the common characteristics of life?

Answer 1

Growth, metabolism, response to stimuli, movement, and reproduction

Question 2

What is the smallest unit of life?

Answer 2

Cell

Question 3

True/False. New cells arise only from pre-existing cells.

Answer 3

True

Question 4

True/False. Multicellular organisms cannot arise from a single cell.

Answer 4

False. It can.

Question 5

What is central dogma?

Answer 5

Central Dogma is the major principal which allows cells to take control of itself.

Question 6

What is the function of DNA?

Answer 6

DNA stores genetic information

Question 7

Why is genetic information written on DNA expressed?

Answer 7

To produce a product which is used to control cellular activity.

Question 8

How are copies of cells made?

Answer 8

DNA replication

Question 9

What are the steps of central dogma?

Answer 9

DNA synthesis -> DNA -> RNA synthesis -> RNA -> protein synthesis -> protein

Question 10

What is the difference between prokaryotes and eukaryotes?

Answer 10

Prokaryotes do not have defined nucleus while eukaryotes have a true nucleus.

Question 11

Aside from nuclei, what do prokaryotes lack?

Answer 11

membrane-bound organelles

Question 12

Are prokaryotes smaller or larger than eukaryotes?

Answer 12

Smaller

Question 13

What are macromolecules?

Answer 13

Macromolecules are building blocks of life.

Question 14

What are the four different kinds of blocks?

Answer 14

Sugars, fatty acids, amino acids and nucleotides

Question 15

When each of the four building blocks are organized, what major cellular structures are built?

Answer 15

Sugars – polysaccharides
Fatty acids – fats, lipids, membranes
Amino acids – proteins
Nucleotides – nucleic acids

Question 16

How are polymers formed?

Answer 16

When monomers of sugars, amino acids and nucleotides are linked together.

Question 17

What do all cells use as catalysts? What else?

Answer 17

All cells use proteins as catalysts. Nucleotides especially RNA can also be used as catalysts.

Question 18

How are fatty acids different from sugars, amino acids and nucleotides?

Answer 18

Fatty acids usually do not polymerize the same way sugars, amino acids, and nucleotides would do. They group together to form various membranes found in cells.

Question 19

What one feature of phospholipids?

Answer 19

They have hydrophilic head group and hydrophobic tails

Question 20

What strain of the bacterial pathogen streptococcus pneumonieae causes pneumonia and what strain does not?

Answer 20

Smooth (S) strain causes pneumonia and rough (R) strain does not.

Question 21

How is R strain converted to an S strain?

Answer 21

When different macromolecules from S strain extracts and purifies, transfers it into the R strain, and the R strain receives DNA of S strain.

Question 22

What happens to the R strains that receive other molecules (not DNA) of S strain?

Answer 22

They do not get converted to an S strain.

Question 23

Describe the central dogma in eukaryotes in steps.

Answer 23

DNA -> synthesis of mRNA in the nucleus -> RNA -> mRNA needs to cross the nuclear membranes to get into cytoplasm so it moves via nuclear pore -> synthesis of protein -> protein

Question 24

What is the function of ribosomes in the cytoplasm during the central dogma in eukaryotes?

Answer 24

Ribosomes translates mRNA into proteins in the cytoplasm.