Lecture 4: Eukaryotes

Question 1

Eukaryote: large cells

Answer 1

• do work slower because molecules have longer diffusion path
• must have division of labour

Question 2

Eukaryote: large genomes

Answer 2

• add metabolic burden

Question 3

Eukaryote: phagocytosis

Answer 3

• bring food in, breakdown in phagosome, then diffuse products in cytosol
• much more efficient because it turns a public good into private

Question 4

Eukaryote: endosymbiosis

Answer 4

The cell may ingulf something that doesn’t want to be digested and it may take over
- sometimes it may be mutualistic or it may be obligate (ex. mitochondria)

Question 5

Eukaryote: Internal membranes

Answer 5

ex. mitochondria: provide extensive active membrane system without requiring a large and expensive genome
ex. endoplasmic reticulum: helps achieve high rates of biosynthesis

Question 6

Eukaryote: Nucleus

Answer 6

ensures only mRNAs are presented to ribosomes

Question 7

Eukaryote: Cytoskeleton

Answer 7

internal system of interlinked filaments and tubules that power dynamics
• microfilament: generate force when growing end is attached to membrane
• microtubules: hollow cylinders formed of tublin (drag/drop objects)
• Intermediate tubules: bear tension

Question 8

Eukaryote: Mitosis

Answer 8

• allows eukaryotes to replicate faster than bacteria (makes many origins)

Question 9

Eukaryote: Multicellularity

Answer 9

• cell to cell junction is needed to form multicellular organisms

Question 10

Eukaryote: SEX!!!!!

Answer 10

• vegetative cycle: growth and reproduction

* sexual cycle: sexual fusion and sexual division