intro

Question 1

Why are cells small?

Answer 1

in order to transfer materials from outside the cell into the cell, to work quickly, surface to volume ratio must be maximized

Question 2

Large cells are…

Answer 2

multinucleated

Question 3

Complexity of cells

Answer 3

not random! ordered and consistent eg: PCD

Question 4

Cell Biology is…

Answer 4

Reductionist–knowledge of the parts explains the whole

Question 5

Tools used to look at cells

Answer 5

Modern Compound microscope

transmission electron micrscope

Question 6

Robert Hooke

Answer 6

“cell” using first compound microscope in 1665

Question 7

Anton van Leeuwenhoek

Answer 7

Made really good lenses, first to describe many single celled organisms “animalcules”

Question 8

Matthias Schleiden & Theodore Schwann

Answer 8

first two tenants of cell bio

1. all organisms composed of one or more cells
2. cell = structural unit of life

Question 9

Pasteur

Answer 9

environment causes growth, not spontaneous if left in closed vessel–lead to 3rd tenant

Question 10

3rd tenant

Answer 10

cells can arise only by division from an existing cell

–Rudolf Virchow

Question 11

Why are these exciting times for cell bio?

Answer 11

low cost genome sequencing

Question 12

Stems cells and gene regeneration

Answer 12

take own cells and derive tissues from them

Question 13

Problem with growing full organs

Answer 13

complex! not just a bundle of tissue–have specific organization

Question 14

synthetic biology

Answer 14

make life from scratch–could disrupt the 3rd tenant
J Craig Venter–alter genome in bacteria so it has a new set of characteristics
creating artificial DNA–new base pairs

Question 15

Why are chemical interactions so important in the cell?

Answer 15

because at the molecular level all events are triggered by another

Question 16

T or F: movement of molecules is smooth

Answer 16

F–make use of brownian movement in order to fit in to small spaces because the cell is very crowded

Question 17

Basic cell properties:

Answer 17

complex 
genetic program and means to use it 
reproduce 
acquire and utilize energy 
carry out chem rxns 
engage in mechanical activities 
interact with environment 
self regulation 
evolve

Question 18

timeline of life

Answer 18

photosynthetic bacteria–cyanobacteria–eukaryotes

Question 19

cyanobacteria importance

Answer 19

took in CO2 and spewed out O2 which was toxic to many organisms but lead to the great oxygenation event 2.3 bya

Question 20

Initial eukaryotes

Answer 20

stuck together and began to specialize in function leading to first multicellular organisms

Question 21

Importance of cambrian time period

Answer 21

cambrian explosion–lots of life occured

Question 22

3 domains of the phylogenetic tree of life

Answer 22

Bacteria, Archaea, and Eucaryota

Question 23

LUCA

Answer 23

Last universal common ancestor (branch pt)

Question 24

Theory of endosymbiosis

Answer 24

anaerobic heterotrophic prokaryote engulfed an aerobic prokaryote which was not digested because it helped the cell by making ATP and thus created an aerobic heterotrophic prokaryote with a mitochondria

Question 25

T or F: chloroplasts came before mitochondria

Answer 25

F–some engulfed photosynthetic cyanobacteria which lead to the creation of cholorplasts after mitochondria

Question 26

What happened after an aerobic prokaryote was engulfed?

Answer 26

pre-eukaryote started getting lots of folds which lead to the primitive eukaryote w/ a nuclear envelope precursor

Question 27

Characteristics common to prokaryotes and eukaryotes

Answer 27

similar plasma membrane constituted of lipids
both us DNA, similar genetic code
similar transcription and translation mechanisms
similar metabolic pathways
(plants and cyanobacteria–similar photosynthesis)
LUCA had to have all of these things

Question 28

Unique characteristics of Eukaryotes

Answer 28

nucleus--stores DNA 
separate chromosomes 
membraneous organelles 
presence of mitochondria 
complex cytoskeleton 
ability to phagocytose and endocytose material 
diploidy or polyploidy 
cell division, mitosis--mitotic spindle 
sexual reproduction--meiosis