3.4.5 Species and Taxonomy

Question 1

.Q: What defines organisms as belonging to the same species?

Answer 1

A: Organisms are considered the same species if they can produce fertile offspring together.

Question 2

Q: Why is courtship behavior important in species recognition?

Answer 2

A: Courtship behavior is crucial as it ensures that mating occurs between the same species, helping individuals to recognize suitable mates and facilitate successful reproduction.

Question 3

Q: What is a phylogenetic classification system?

Answer 3

A: A phylogenetic classification system arranges species into groups based on their evolutionary origins and relationships, using a hierarchy where smaller groups are nested within larger groups.

Question 4

Q: What is the hierarchy of taxa in the phylogenetic classification system?

Answer 4

A: The hierarchy is: domain, kingdom, phylum, class, order, family, genus, and species.

Question 5

Q: How are species universally identified in taxonomy?

Answer 5

A: Species are identified by a binomial nomenclature consisting of the genus name and the species name, e.g., Homo sapiens.

Question 6

Q: What is a taxon?

Answer 6

A: A taxon (plural: taxa) is a group of one or more populations of organisms that form a unit in the classification hierarchy..

Question 7

Q: What is the role of advances in immunology in taxonomy?

Answer 7

A: Advances in immunology help to clarify evolutionary relationships by analyzing immune responses and proteins, providing insights into how closely related different species are.

Question 8

Q: How does genome sequencing contribute to understanding evolutionary relationships?

Answer 8

A: Genome sequencing provides detailed genetic information, allowing scientists to compare DNA sequences between species and better understand their evolutionary connections.

Question 9

Q: Describe the role of the genus in binomial nomenclature.

Answer 9

A: The genus is the first part of the binomial name and groups species that are closely related. It is always capitalized.

Question 10

Q: Describe the role of the species name in binomial nomenclature.

Answer 10

A: The species name is the second part of the binomial name and specifies the exact species within the genus. It is always written in lowercase.

Question 11

Q: What is the primary purpose of using a hierarchical classification system in taxonomy?

Answer 11

A: The hierarchical system organizes species into nested groups, reflecting their evolutionary relationships and making it easier to study and understand the diversity of life.

Question 12

Q: Explain the term “phylogeny.”

Answer 12

A: Phylogeny refers to the evolutionary history and relationships among species or groups of species.

Question 13

Q: How does phylogenetic classification differ from traditional Linnaean classification?

Answer 13

A: Phylogenetic classification is based on evolutionary relationships, while traditional Linnaean classification is based on physical characteristics and does not necessarily reflect evolutionary histories

Question 14

Define the term “phylogenetic tree.”

Answer 14

A phylogenetic tree is a diagram that represents the evolutionary relationships among different species or groups of species.
It is based on the common ancestry and evolutionary history of the organisms.

Question 15

A student is studying the classification of different species of flowering plants. The student is using a hierarchical classification system.

Describe the hierarchy of taxa used in the classification of these plants from the broadest to the most specific level.

Answer 15

Mark Scheme:

Domain (1 mark)
Kingdom (1 mark)
Phylum (1 mark)
Class (1 mark)
Order (1 mark)
Family (1 mark)
Genus (1 mark)
Species (1 mark)
Total: 8 marks

Question 16

The binomial nomenclature system is used to name species.

(a) What is binomial nomenclature?

(b) Give an example of a species name and identify its genus and species components.

Total: 4 marks

Answer 16

Mark Scheme:

(a) Definition (2 marks):

Binomial nomenclature is a system of naming species using two names: the genus name and the species name.
The genus name is capitalized, and the species name is written in lowercase.
(b) Example and identification (2 marks):

Example: Homo sapiens
Genus: Homo (1 mark)
Species: sapiens (1 mark)

Question 17

Explain the importance of courtship behavior in maintaining species integrity.

Total: 4 marks

Answer 17

Mark Scheme:

Courtship behavior helps individuals identify and recognize potential mates of the same species. (1 mark)
It ensures that mating occurs between members of the same species, leading to the production of fertile offspring. (1 mark)
It can involve specific signals or rituals that are unique to each species, which helps prevent interbreeding with other species. (1 mark)
This behavior increases the likelihood of successful reproduction and species survival. (1 mark)

Question 18

Advances in genome sequencing have provided new insights into the relationships between species.

Explain how genome sequencing can be used to clarify evolutionary relationships.

Total: 4 marks

Answer 18

Mark Scheme:

Genome sequencing provides detailed genetic information about the DNA of different species. (1 mark)
By comparing the DNA sequences, scientists can identify similarities and differences between species. (1 mark)
The degree of genetic similarity or difference can indicate how closely related species are and help construct more accurate phylogenetic trees. (1 mark)
This information can reveal evolutionary lineages and divergence points between species. (1 mark)