Comprehensive Course Notes

Question 1

Cycle 1

Viruses are obligate parasites :

Answer 1

must infect a cell (host) to replicate

Question 2

Cycle 1

Retroviruses :

Answer 2

Viruses made of RNA that use RT to convert their RNA to DNA

Question 3

Cycle 1

Viruses Composition :

Answer 3

Viruses Composition : Protein shell w/ nucleic acid genome inside

Question 4

Cycle 1

What type of Cells does HIV target? How?

Answer 4

1. Virion fuses w/ host immune cell → integrats its genome into hosts’ nuclear genome
2. Viral RT reverse transcribes viral RNA to ds DNA
3. Viral integrase [protein] splices viral DNA into host DNA
4. Viral DNA is transcribed + translated -> forms new virions

Question 5

Cycle 1

Animal Virus Infection

Answer 5

1. Viral particles move randomly until contact w/ surface of a host cell
2. Viruses infect host cell → to rep. its DNA, hijack machinery → host cell manufactures new viruses → virions released from host cell
   > Viruse w/o envelope: bind to plasma mem→ endocytosis
   > some enveloped viruses (like HIV) enter cell by fusion of their envelope w/ host plasma mem

Question 6

Cycle 1

Convergent Evolution

Answer 6

Independent evolution of comparable traits in unrelated species *Ex: birds & bats both have wings - but evolved them seperately

Question 7

Cycle 1

Scala of Natura Theory

Answer 7

“Simple organisms evolve into more complex ones, moving up Scale of Nature”

Question 8

Cycle 1

Speciation

Answer 8

Lineages diverge into daughter lineages

Question 9

Cycle 1

Biogeoraphy

Answer 9

similar species in different places, but few changes have occured

Question 10

Cycle 2

The location of DNA in eukaryotic and prokaryotic cells

Answer 10

Prokaryotes = Nucleoid
Eukaryotes = Nucleus

Question 11

Cycle 2

Do all Cells have the Ability to Replicate?

Answer 11

Not all cells have the ability to rep
* Cells that CAN are Stem cells
* Ex: Neurons never replicate

Question 12

Cycle 2

What SA:V Ratio Must be Maintained? Why?

Answer 12

High SA:V Ratio
* Because a Low ratio => V is limited to SA of plasma mem; as cell grows, ratio decreases until cell can no longer function

Question 13

Cycle 2

Prokaryotic Cell Division

Answer 13

B Period: Growth occurs (from birth to DNA rep)

** C Period: **Chromosomes rep → separated to opposite ends of cell

D Period: **Binary fission; mem. pinches together between cells ⇒ 2 daughter cells are formed

Analogy: B= Gap phase, C = S Phase, D = Cell Division

Question 14

Cycle 2

Animal Life Cycle

Answer 14

Animal Life Cycle
Gametes arise by Meiosis [Meiosis-> Gametes]

Zygote divides by Mitosis [Zygotes -> Mitosis]

Question 15

Cycle 2

Plants and some fungi life cycle

Answer 15

Plants and some fungi life cycle
Gametes arise by Mitosis [Mitosis -> Gametes]

Spores divide by Meiosis [Spores -> Meiosis]

Question 16

Cycle 2

Algae and Some Fungi Life Cycle

Answer 16

Algae and Some Fungi Life Cycle
Gametes arise by Mitosis [Mitosis -> Gametes]

Zygote divide by Meiosis [Zygote -> Meiosis

Question 17

Cycle 2

Homologous chromosomes

Answer 17

Similar but nonidentical chromo pairs received from parents: **1 from mom & 1 dad

*Genes w/ same corresponding loci but Diff alleles

Question 18

Cycle 2

Chromosome segregation

Answer 18

Equal distribution of daughter chromosomes into each daughter cell that results from cell division