(bio) Unit 0 - The beginning of the end

Question 1

Who invented the light microscope

Answer 1

Hans Lippershey , Hans and Zacharias Janssen around 1590

Question 2

Cell Theory ; who discovered it and what did they see

Answer 2

Robert Hooke ; viewed slices of tree bark “cellula”

Question 3

What did Antoine Van Leeuwenhoek do/observe? (2)

Answer 3

• Worked with glass
• became a huge improvement in quality of lenses
  (300x magnification became possible) of compound microscope
• First to observe single celled protists from pond water , bacteria, blood cells, banded pattern in muscle cells, giarda and sperm

Question 4

Robert Brown the botanist and the cell theory

Answer 4

noticed that every plant cell contained a round structure (nucleus)

Question 5

Matthias Schleiden (another botanist)

Answer 5

• all plant tissues are composed of cells
• embyronic plant always arose from a single cell

Question 6

Theodor Schwann (zoologist)

Answer 6

• similar observations in animal cells
• recognition of structural similarities between plants and animals

Question 7

Who formulated the cell theory

Answer 7

Schwann

Question 8

Describe the cell theory (3 facts)

Answer 8

1. All organisms consist of one or more cells
2. The cell is the basic unit of structure for all organisms
3. all cells arise only from pre-existing cells

Question 9

Describe the Scientific Method (5)

Answer 9

• make observations
• use inductive reasoning to develop a hypothesis
• Make predictions based on hypothesis
• Make further observations or design and carry out controlled experiments to test hypothesis
• interpret results to see if they support your hypothesis

Question 10

Describe a theory

Answer 10

• a hypothesis that has been tested critically (under many different conditions/ investigators/approaches)
• widely accepted by most scientists in the field
• “solid ground” of science

Question 11

What is more solid than a theory

Answer 11

a LAW

Question 12

Basic Properties of all Cells (5)

Answer 12

1. Highly complex and organized
2. Use the same “genetic program” - Central Dogma
3. Acquire and use energy to carry out chemical rxns
4. Engage in mechanical activities (transport/ assembly/ movement )
5. Respond to signals (environmental, molecular)

Question 13

What are the two domains of prokaryotes?

Answer 13

• eubacteria (all have cell walls)
• archaebacteria (all have cell walls, best known are extremophiles; halophiles, acidophiles, thermophiles )

Question 14

What are the 4 groups of eukaryotes?

Answer 14

• protists (single cell)
• fungi
• plants
• animals

Question 15

Describe the ‘generic’ prokaryotic cell

Answer 15

• no membrane bound nucleus
• ‘naked’ DNA (fewer proteins), single, circular strand
• cell wall in addition to plasma membrane
• very small, no need for cytoskeletal transport systems

Question 16

Describe protists and give examples

Answer 16

a type of eukaryote - very diverse group
- mostly single cells, but some colonies

ex. algae, water molds, slime moulds, protozoa

Question 17

Describe fungi

Answer 17

a type of eukaryote
- single cells (yeasts) and multicellular (mushrooms)
- cell walls, heterotrophs
- dependent on external source of organic compounds

Question 18

Describe plants

Answer 18

a type of eukaryote
- multicellular
- have cell walls
- autotrophs

Question 19

Describe animals

Answer 19

a type of eukaryote
- multicellular
- no cell walls
- heterotrophs

Question 20

Describe the endomembrane system

Answer 20

• internal membranes that are either in direct contact or connected via transfer of vesicles (sacsof membrane)

this includes; nuclear envelope, membrane. ER, golgi apparatus, lysosomes, vacuoles

Question 21

What two organelles have their own genomes

Answer 21

1. Mitochondria - generate energy to power cell
2. Chloroplasts - using energy from sunlight convert CO2 derived carbon to carbohydrate

they both contain dna that encodes SOME of their own proteins

Question 22

Describe the role of the Rough ER and the Golgi apparatus in the Secretory Pathway

Answer 22

Rough ER: synthesis of proteins for … export, insertion into membranes, lysosomes

Golgi Apparatus: collection, packaging, and distribution

Question 23

Describe the endocytic pathway

Answer 23

• cell ‘stomachs’ have enzymes that can digest biological macromolecules such as
• worn-out organelles
• material brought into cell by phagocytosis

Question 24

How did eukaryotic ells acquire mitochondria and chloroplasts?

Answer 24

Endosymbiont Theory
- organelles evolved to gradually become more complex
- eukaryotes originally originated as predators (certain organelles evolved from smaller prokaryotes engulfed by larger cell

Question 25

Evidence for supporting the endosymbiont theory (5)

Answer 25

Mitochondria and chloroplasts…
1. Similar size, reproduce by fission
2. Have double membranes , engulfing mechanism
3. have their own ribosomes
4. Have their own genomes
5. genetically similar to ‘parent’ bacteria , not eukaryotic cell it was engulfed by

Question 26

Importance of Cytoskeleton

Answer 26

• cell shape, motility, movement
• movement of materials within cells (eg chromosomes during mitosis)

Question 27

fun little thing: contribution of model organism e. coli

Answer 27

DNA replication, gene transcription, translation

Question 28

fun little thing: contribution of model organism saccharomyces cerevisae

Answer 28

cell cycle

Question 29

fun little thing: contribution of model organism Arabidopsis thaliana

Answer 29

all flowering plants closely related

Question 30

fun little thing: contribution of model organism drosophila melanogaster

Answer 30

genetics, development

Question 31

fun little thing: contribution of model organism C. elegans (“the worm”)

Answer 31

First animal genome to be sequenced

Question 32

Fun little thing: contribution of model organism mouse

Answer 32

‘model mammal’
Genetics well understood