Ch 1 review

Question 1

What is the importance of a hierarchical
classification system?

Answer 1

-helps us categorize organisms so we can more easily communicate biological information
-taxonomy uses hierarchical classification as a way to help scientists understand and organize the diversity of life on our planet

Question 2

Why do taxonomists sometimes use
intermediate taxa, such as superfamily
and suborder, to classify organisms?

Answer 2

Sometimes diversity is so vast within a group that intermediate taxa is required to classify organisms further
-e.g. within the class Insecta, taxonomists group insects into intermediate taxa, such as
superfamily and suborder

Question 3

Use a specific example to explain how a
population’s lack of genetic diversity may
impact an ecosystem

Answer 3

Irish Potato Famine
-genetically identical crops and one disease wiped out all potatoes in Ireland
-caused starvation and disease

Monoculture
-genetically uniform farms, known as monocultures, are systems with almost no biodiversity
-without the diversity typically found in an ecosystem, monocultures are especially vulnerable to diseases and pathogens
-these diseases can decimate populations in which all individuals are equally at risk

Question 4

What factors may be contributing to the loss
of honeybees?

Answer 4

insecticides (neonicotinoids)
-affect central nervous system of bees and contaminates nectar, when taken back to hive

cold weather, lack of genetic diversity (virus/disease can kill all bees)

Question 5

Suppose scientists want to design a chemical
that targets mites that cause allergies. How
might they go about it?

Answer 5

they should classify the mites and find out which species is causing allergies, so that they’re not just killing any mites that could be helpful to the environment

Question 6

Consider the biological definition of a species.
(a) Use the lion and the tiger as an example to
explain this definition

Answer 6

not the same species so they can’t mate and produce offspring

Question 7

Consider the biological definition of a species.
(b) Would scientists use this definition to
classify a dinosaur? Justify your answer.

Answer 7

no biologists cannot rely on the biological concept of species to define all species, because some
organisms do not reproduce sexually, have gone extinct*, or have not been observed to reproduce

Question 8

The lion and the tiger belong to the same
family. The gray wolf and the brown bear
belong to the same order. Which pair of animals
is more closely related? Justify your answer

Answer 8

the lion and tiger in the same family are more closely related because it’s ranked closer to the bottom and lower ranks are more closely related

Question 9

The ermine and the mink are commonly found
in the boreal forests of Ontario. Although the
two mammals look very similar (see below),
they are considered distinct species. Explain
why

Answer 9

-deeper analysis reveals that there are major differences between the two
-as well, they can’t mate and produce offspring
= different species