Biology Lecture Test 1

Front 1

for most ecosystem___is the ultimate source of energy, and energy leaves the ecosystem in form of__.

Back 1

sunlight, heat

Front 2

what is a hypothesis

Back 2

tentative explanation that can be tested and falsifiable

Front 3

all mammals so far studied have hair, produce milk, an dhave 3 middle ear bones. we have just discovered a new kind of animal that has hair and produces milk. we would predict that it has 3 bones n its middle ear. this type of reasoning is

Back 3

deductive

Front 4

why are water molecules cohesive?

Back 4

b/c theyform hydrogen bonds

Front 5

you have been hired as a chemist and are examining the paperwork of a newly discovered atom. You read taht this atom has a tendency to lose 2 electrons. based on what you know, this would result in the formation of

Back 5

an ion

Front 6

which of the following are nitrogenous bases of the pyrimidine type?

Back 6

cytosine and uracil

Front 7

biological molecules primarily are joined by

Back 7

covalent bonds

Front 8

an isotope of the element fluorine is commonly used in positron emission tomography scans. the non-isotope form of fluorine has 9 electrons, 9 protons, and 10 neutrons. based on your knowledge of isotopes, which of the following could be true about the fluorine isotope used in PET scans?

Back 8

isotope form has 9 neutrons

Front 9

in the term trace element, the modifier trace means

Back 9

the element is required in very small amount

Front 10

which of the following would be regarded as compounds

Back 10

H2O and CH4, but not O2

Front 11

an atom's nucleus is composed of

Back 11

protons and neutrons

Front 12

polar molecules

Back 12

have an unequal distribution of electric charge

Front 13

all the following are true of hydrogen gas, H2, except

Back 13

H2 is polar

Front 14

milk of magnesia is often used to treat stomach upset. it has a pH of 10. based on this info, which of the following is true?

Back 14

milk of magnesia is a base

Front 15

the fact that salt dissolves in water is best explained by

Back 15

the polar nature of water molecuels

Front 16

a living thing composed mostly of water can withstand sunny, hot weather without their body temp soaring quickly. which of the following best explains why

Back 16

water has a high specific heat

Front 17

which of the following results from a transfer of electrons between atoms

Back 17

ionic bond

Front 18

which of the following is the most dense

Back 18

liquid water

Front 19

the water strider skates along the surface of water due to a property of liquids called

Back 19

surface tension

Front 20

scientists now recommend a diet rich in antioxidants to stay healthy. what occurs at the atomic level to explain the reasonging behind this recommendation?

Back 20

antioxidants stop the chain reaction of cellular damage caused by free radicals