Cells, Water, and Chemicals

Question 1

natural selection

Answer 1

traits that lead to better reproduction and survival continue while others die out

Question 2

cells

Answer 2

complex machine that survives and builds more similar machines

Question 3

diffusion

Answer 3

moves things over short distances from region of high to low concentration

Question 4

covalent bonds

Answer 4

formed by sharing electrons between 2 atoms

Question 5

hydrogen bonds

Answer 5

electrical attraction between the positively and negatively charged ends

Question 6

adhesion

Answer 6

polar water molecules are electrically attracted to polar and charged molecules

Question 7

solvent (water property)

Answer 7

binds, suspends, hydrophilic

Question 8

cohesion

Answer 8

polar water binds to polar water

Question 9

high specific heat of water

Answer 9

requires a higher heat input to increase temperature than many other sources

Question 10

what do fossil records show about evolution?

Answer 10

fossils show that species have vanished but new species have emerged; make it clear evolution happened slowly

Question 11

what causes polar covalent bonds?

Answer 11

differences in electronegativity cause unequal sharing

Question 12

how does the density of liquid water compare to ice?

Answer 12

ice is less dense due to greater spacing which allows ice to float