Lecture 4

Question 1

First cells

Answer 1

• Bacteria + Archaea = prokaryotes
• Molecular evidence proves that archaea and eukarya are more closely related than bacteria and archaea

Question 2

Who/What is LUCA?

Answer 2

• Last Universal Common Ancestor
• A common ancestor from which all present day organisms are descended

Question 3

Theory of endosymbiosis

Answer 3

states that the mitochondria and chloroplast in eukaryotic cells were once aerobic bacteria (prokaryote) that were ingested by a large anaerobic bacteria (prokaryote).

Question 4

Evidence supporting prokaryotic origin of mitochondria and chloroplasts

Answer 4

• Transcription and translation
• ETC
• DNA sequence analysis

Question 5

Endomembrane system

Answer 5

• Another characteristic feature of eukaryotic cells
• Collection of internal membranes dividing the cell into structurally and functionally distinct regions
• These regions include the nuclear envelope, the endoplasmic reticulum (ER), and the Golgi complex

Question 6

Gene Transfers

Answer 6

1. Vertical gene transfer
2. Horizontal gene transfer

Question 7

Vertical gene transfer

Answer 7

Genetic inheritance from one generation to the next WITHIN a species

Question 8

Horizontal gene transfer

Answer 8

Genetic inheritance between unrelated species

Question 9

Relative and absolute fossil dating

Answer 9

• Relative dating puts geologic events in chronological order without requiring that a specific numerical age be assigned to each event.
• Absolute fossil measure the physical properties of an object itself and use these measurements to calculate its age

Question 10

Common attributes for all forms of cellular life

Answer 10

1. Lipid molecules form a membrane bilayer that defines the cell
2. A genetic system based on DNA
3. A system of information transfer: DNA to RNA to protein
4. A system of protein assembly using messenger RNA and transfer RNA using ribosomes to polymerize the amino acids into peptides
5. Reliance on proteins as the major structural and catalytic molecule
6. Use of ATP as the molecule of chemical energy
7. The breakdown of glucose by the metabolic pathway of glycolysis to generate ATP (chemiosmosis, substrate-level phosphorylation)

Question 11

Cell theory

Answer 11

• All organisms are composed of one or more cell
• The cell is basic structural and functional unit of all living organisms
• Cells arise only from the division of preeexisting cells