Question 1

On an evolutionary tree,any group that includes a common ancestor and all of its descendants is called monophyletic ("one-tribe").Recall the current evolutionary tree for Bacteria,Archaea,and Eukarya.According to this tree,are all organisms alive today monophyletic?

Accepted Answer

A)  yes
B)  no A

Question 2

How does a scientific theory differ from a scientific hypothesis?

Accepted Answer

A)  Theories are proposed to test scientific hypotheses.
B)  A theory is an explanation for a very general phenomenon or observation;hypotheses treat more specific observations.
C)  A hypothesis is an explanation for a very general phenomenon;theories treat more specific issues.
D)  Theories define scientific laws;hypotheses are used to set up experiments. B

Question 3

On an evolutionary tree,any group that includes a common ancestor and all of its descendants is called monophyletic ("one-tribe").Recall the current evolutionary tree for Bacteria,Archaea,and Eukarya.Are prokaryotes monophyletic?

Accepted Answer

A)  yes
B)  no B

Question 4

What is the difference between experimental replicates and experimental controls?

Accepted Answer

A)  Replicates are "repeat" samples under a given condition.
B)  Replicates decrease sample size.
C)  All replicates in an experiment are found under the control conditions.
D)  All replicates differ from other replicates by a single factor.

Question 5

In comparison to eukaryotes,prokaryotes _____.

Accepted Answer

A)  are more structurally complex
B)  are larger
C)  are smaller
D)  lack any cell membranes

Question 6

The best experimental design _____.

Accepted Answer

A)  includes a large number of replicates for each condition
B)  includes a control
C)  alters only one condition between the controls and the experimental condition
D)  includes a large number of replicates,a control,and alters only one condition between the controls and the experimental condition

Question 7

Which of the following statements about cells is true? A cell is _____.

Accepted Answer

A)  only found in multiples of two,because single cells cannot exist independently
B)  always between 200 and 500 micrometers in diameter
C)  characteristic of eukaryotic but not prokaryotic organisms
D)  characteristic of both prokaryotic and eukaryotic organisms

Question 8

Which of the following observations led to the conclusion that the food competition hypothesis for giraffe neck length might not be correct?

Accepted Answer

A)  In the populations studied to date,giraffes never feed high in trees.
B)  In certain populations at certain times of year,only male giraffes feed high in trees.
C)  Male and female giraffes spend most of their time feeding low in trees.
D)  Giraffes rarely die of starvation,so food availability is unimportant.

Question 9

You find yourself standing next to a beautiful rosebush.Based on the current evolutionary data,which of the following do you and the rose have in common?

Accepted Answer

A)  You both are multicellular.
B)  You both lack a membrane-bound nucleus.
C)  You are both prokaryotic.
D)  You and the rose have nothing in common.

Question 10

Recall the caterpillar experiment,where caterpillars born in the spring looked like flowers,and caterpillars born in the summer looked like twigs.What is the most likely selective advantage for this difference in body shape?

Accepted Answer

A)  Looking like their food sources allows the caterpillars to move through their environment more efficiently.
B)  Development into the adult moth form is faster for caterpillars shaped like twigs than like flowers.
C)  Looking like their food source lets the caterpillars blend into their surroundings,and thus avoids predation and increases survival rates.
D)  Looking like their food source will increase the caterpillars' feeding efficiency;this would increase their growth rate and survival rate.

Question 11

Figure 1.1
The following experiment is used for the corresponding question(s).
A researcher discovered a species of moth that lays its eggs on oak trees.Eggs are laid at two distinct times of the year: early in spring when the oak trees are flowering and in midsummer when flowering is past.Caterpillars from eggs that hatch in spring feed on oak flowers and look like oak flowers.But caterpillars that hatch in summer feed on oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on the same trees? To answer this question,the biologist caught many female moths from the same population and collected their eggs.He put at least one egg from each female into eight identical cups.The eggs hatched,and at least two larvae from each female were maintained in one of the four temperature and light conditions listed below.
  
Figure 1.1
In each of the four environments,one of the caterpillars was fed oak flowers,the other oak leaves.Thus,there were a total of eight treatment groups (4 environments × 2 diets).
-Refer to Figure 1.1.Recall that eggs from the same female were exposed to each of the eight treatments used.This aspect of the experimental design tested which of the following hypotheses?

Accepted Answer

A)  The longer day lengths of summer trigger the development of twig-like caterpillars.
B)  Differences in air pressure,due to elevation,trigger the development of different types of caterpillars.
C)  Differences in diet trigger the development of different types of caterpillars.
D)  The differences are genetic-a female will produce all flowerlike caterpillars or all twig-like caterpillars.

Question 12

Current evolutionary data groups land plants with green algae and red algae.Brown algae,which you often find in the same habitat as red and green algae,is part of a distantly related group that includes the diatoms.This suggests that _____.

Accepted Answer

A)  green algae and land plants are not closely related
B)  green algae are very closely related to the brown algae
C)  green,red,and brown algae form a single taxon unto themselves
D)  the term "algae" does not indicate a single taxon

Question 13

If you find a mouse in your basement,it is likely Mus musculus.Peromyscus leucopus is also common.Or,you may get lucky and find a relatively rare Peromyscus maniculatus instead.Out of these three species,which two are the most closely related (from an evolutionary standpoint)?

Accepted Answer

A)  the two most common: M.musculus and P.leucopus
B)  the two species in the Peromyscus genus
C)  the two with the species name that starts with "m" because species that start with the same first letter are closely related
D)  There is no way to tell with the information provided in this question.

Question 14

Agrobacterium is a type of bacteria that infects plants and causes them to form tumors.You are asked to determine how long a plant must be exposed to the bacteria to become infected.Which of the following experiments will provide the best data for that question?

Accepted Answer

A)  determining the survival rate of Agrobacterium to different concentrations of an antibiotic
B)  determining the number of tumors formed on a plant depending on the concentration of Agrobacterium applied
C)  determining the concentration of Agrobacterium in different soil environments
D)  determining the number of tumors formed on a plant depending on how long it is exposed to Agrobacterium

Question 15

Lance Armstrong just finished third (by about 5 minutes)in the 2009 Tour de France cycling race.This was an incredible feat for the 37-year-old father of 4.First and second-place winners,Alberto Contador (age 27)and Andy Schleck (age 24),respectively,have no children.Which of these three men shows the greatest evolutionary fitness?

Accepted Answer

A)  Alberto Contador,because he won the race.
B)  Lance Armstrong,because he came in third at the advanced age of 37!
C)  Andy Schleck,because he beat the highly experienced Lance Armstrong.
D)  Lance Armstrong,because he has reproduced.

Question 16

What do nodes on a phylogenetic tree represent?

Accepted Answer

A)  environmental events that caused speciation
B)  new kingdoms or domains
C)  ancestral groups that split into two or more descendant groups
D)  groups that got new names

Question 17

Starting from the wild mustard Brassica oleracea,breeders have created the strains known as Brussels sprouts,broccoli,kale,and cabbage.Which of the following statements is supported by this observation?

Accepted Answer

A)  In this species,there is enough heritable variation to create a variety of features.
B)  Heritable variation is low-otherwise the wild strain would have different characteristics.
C)  Natural selection has not occurred very frequently in the wild populations.
D)  In this species,most of the variation present is due to differences in soil,nutrition,amount of sunlight,or other aspects of the environment.

Question 18

Figure 1.1
The following experiment is used for the corresponding question(s).
A researcher discovered a species of moth that lays its eggs on oak trees.Eggs are laid at two distinct times of the year: early in spring when the oak trees are flowering and in midsummer when flowering is past.Caterpillars from eggs that hatch in spring feed on oak flowers and look like oak flowers.But caterpillars that hatch in summer feed on oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on the same trees? To answer this question,the biologist caught many female moths from the same population and collected their eggs.He put at least one egg from each female into eight identical cups.The eggs hatched,and at least two larvae from each female were maintained in one of the four temperature and light conditions listed below.
  
Figure 1.1
In each of the four environments,one of the caterpillars was fed oak flowers,the other oak leaves.Thus,there were a total of eight treatment groups (4 environments × 2 diets).
-Refer to Figure 1.1.In every case,caterpillars that feed on oak flowers look like oak flowers.In every case,caterpillars that were raised on oak leaves looked like twigs.These results support which of the following hypotheses?

Accepted Answer

A)  The longer day lengths of summer trigger the development of twig-like caterpillars.
B)  Differences in air pressure,due to elevation,trigger the development of different types of caterpillars.
C)  Differences in diet trigger the development of different types of caterpillars.
D)  The differences are genetic a female will produce all flowerlike caterpillars or all twig-like caterpillars.

Question 19

Figure 1.1
The following experiment is used for the corresponding question(s).
A researcher discovered a species of moth that lays its eggs on oak trees.Eggs are laid at two distinct times of the year: early in spring when the oak trees are flowering and in midsummer when flowering is past.Caterpillars from eggs that hatch in spring feed on oak flowers and look like oak flowers.But caterpillars that hatch in summer feed on oak leaves and look like oak twigs.
How does the same population of moths produce such different-looking caterpillars on the same trees? To answer this question,the biologist caught many female moths from the same population and collected their eggs.He put at least one egg from each female into eight identical cups.The eggs hatched,and at least two larvae from each female were maintained in one of the four temperature and light conditions listed below.
  
Figure 1.1
In each of the four environments,one of the caterpillars was fed oak flowers,the other oak leaves.Thus,there were a total of eight treatment groups (4 environments × 2 diets).
-In Figure 1.1,which of the following is not a plausible hypothesis to explain the difference in caterpillar appearance observed in this population?

Accepted Answer

A)  The longer day lengths of summer trigger the development of twig-like caterpillars.
B)  The cooler temperatures of spring trigger the development of flowerlike caterpillars.
C)  Differences in air pressure,due to differences in elevation,trigger the development of different types of caterpillars.
D)  Differences in diet trigger the development of different types of caterpillars.

Question 20

The phylogenetic tree below _____.

Accepted Answer

A)  depicts the three major domains of life
B)  includes unicellular but not multicellular life
C)  includes unicellular and some forms of multicellular life,but not complex animals and plants
D)  includes noncellular life-forms

Exam 1: Biology and the Tree of Life

On an evolutionary tree,any group that includes a common ancestor and all of its descendants is called monophyletic ("one-tribe") .Recall the current evolutionary tree for Bacteria,Archaea,and Eukarya.According to this tree,are all organisms alive today monophyletic?