quiz 6

Question 1

Characters Used for Phylogenetic Trees

Answer 1

Morphological traits (physical structures like wings or limbs).
Molecular data (DNA, RNA, and protein sequences).
Behavioral traits (specific behaviors of organisms).

Question 2

information in Phylogenetic Branches:

Answer 2

They show evolutionary relationships.
Branch lengths may represent time or genetic changes.

Question 3

Fossils and Phylogenetics:

Answer 3

Fossils help calibrate trees by providing time points.
They offer evidence for extinct common ancestors.

Question 4

Recognizing Common Ancestors:

Answer 4

Nodes in the tree represent common ancestors.

Question 5

Differences Between Monophyletic, Polyphyletic, and Paraphyletic Groups:

Answer 5

Monophyletic: Includes an ancestor and all its descendants (e.g., mammals).
Polyphyletic: Includes unrelated organisms without their common ancestor.
Paraphyletic: Includes an ancestor and some, but not all, of its descendants.

Question 6

Differences Between Archaea and Bacteria:

Answer 6

Cell Wall Composition: Archaea lack peptidoglycan; bacteria have it.
Membrane Lipids: Archaea have ether-linked lipids; bacteria have ester-linked lipids.
Genetics: Archaea are more closely related to eukaryotes in certain genetic processes.

Question 7

Classifying Bacteria:

Answer 7

Based on shape (cocci, bacilli, spirilla).
Gram staining (Gram-positive or Gram-negative).

Question 8

Differences Between Types of Bacteria:

Answer 8

Gram-Positive: Thick peptidoglycan layer, stain purple.
Gram-Negative: Thin peptidoglycan layer, additional outer membrane, stain pink.

Question 9

Processes of Genetic Variation:

Answer 9

Transduction: Transfer of DNA via viruses.
Conjugation: Direct transfer of DNA between bacteria via a pilus.
Transformation: Uptake of DNA from the environment.

Question 10

Bacterial Structures and Functions:

Answer 10

Pili: Help in attachment and conjugation.
Flagella: Aid in movement.
Fimbriae: Shorter than pili; assist in adhesion to surfaces.