origin of life

Question 1

what makes water important for life ?

Answer 1

water is a polar molecule
1. universal solvent

Question 2

what is a solution ?

Answer 2

a solid substance ( the solute)
dissolves in a liquid ( the solvent)

Question 3

polar covalent bond

Answer 3

electrons are drawn to one nucleus more than other because that atoms has greater electronegativity

Question 4

non polar covalent bond

Answer 4

electrons are shared equally (atoms have similar electronegativity

Question 5

what happens when an iconic solid dissolves in water ?

Answer 5

when an iconic solid dissolves in water polar water molecules cluster around the cations and anions preventing them from reassociating

Question 6

what is a hydrogen bond ?

Answer 6

the attraction between the end of one molecule and the hydrogen end of another molecule

Question 7

how do hydrogen bonds form ?

Answer 7

between water molecules and are important in the structure of dan and proteins

Question 8

what is hydrophilic

Answer 8

polar molecules that form hydrogen bonds with water are hydrophilic

Question 9

what is hydrophobic

Answer 9

nonpolar molefules , such as hydro carbons that interact with each other but not with water are hydrophobic

Question 10

what is a specific heat ?

Answer 10

specific heat is the amount of heat energy required to raise the temperature of 1 gram of water by 1 o C = 1 calorie

Question 11

how does water change from water to a gas ?

Answer 11

water has a high heat of vaporization amount of energy required to change water from a liquid to a gas state .

Question 12

cohension

Answer 12

water molecules resist going apart from one another surface tension water molecules at the surface are hydrogen bonded to other water molecules bellow them

Question 13

what are nucleic acids

Answer 13

proteins

Question 14

what are prebiotic molecules ?

Answer 14

large molecules

Question 15

what are biological molecules

Answer 15

enclosed in membranes cells

Question 16

who discovered catalytic properties ?

Answer 16

cech and altman , chemistry 1989 discovery of catalytic properties of ran

Question 17

what is catalytic ran

Answer 17

is a ribozyme

Question 18

how are catalytic rna molecules similar to enzymes

Answer 18

through ribozymes

Question 19

what are the 3 domains of life ?

Answer 19

bacteria
Archie
eukarya

Question 20

what are the unique characteristics of eukaryotic cells ?

Answer 20

indicate that eukaryotes are all derived from a single ancestor

Question 22

how do eukaryotic cells risen ?

Answer 22

eukaryotic cells arose from ancient prokaryotic cells

Question 23

what is the proposed event sequence of life ?

Answer 23

1. loss of cell wall
2. development of a cytoskeleton
3. origin of a nuclear envelope
4. ribosomes became associated within internal membranes
5. formation of digestive vesicles (lysosomes)

Question 24

how did eukaryotes acquire chloroplasts ?

Answer 24

by engulfing but not digesting ancestral cyanobacteria

Question 25

what was the effect of ancestral eukaryotes ?

Answer 25

engulfing cyanobacteria gave rise to glaucophytes , green algae and red algae

Question 26

what is the endosymbiosis theory ?

Answer 26

proposed that mitochondria and plastids arose when one cell engulfed another cell

Question 27

what is primary endosymbiosis

Answer 27

a eukaryote engulfs a cyanobacterium

Question 28

what is a secondary endosymbiosis

Answer 28

the uptake and retnetion of a chloroplast , containing cell by another eukaryotic cell

Question 29

what is Teritary endosymbiosis ?

Answer 29

a cell lost its chloroplast and takes up another protist that had acquired its chloroplast via secondary endosymbiosis

Question 30

what is primary endosymbiosis responsible for ?

Answer 30

account for double membrane of mitochondria and chloroplasts

Question 31

what does secondary endosymbiosis accounts for ?

Answer 31

chloroplasts surrounded by 3 or 4 membranes