1.1 General Properties of cells

Question 1

criteria for self-replication

Answer 1

• be able to obtain and use energy from environment
  
  • other building blocks
  • DNA (instructions)
    ○ a way to read and replicate the DNA/pass on to next generation
  • machinery to undergo division (proteins)
  • plasma membrane (container)

Question 2

Cell theory

Answer 2

1. all living organisms are made of cells
   
   2. cells arise from pre-existing cells
   3. cells are the basic unit of life

Question 3

DNA in bacterial cell

Answer 3

• single circular chromosome
• also carry additional DNA in the form of plasmids

Question 4

plasmids

Answer 4

small circles of DNA that replicate independently of the cell’s circular chromosome

not essential for cell’s survival but may have adaptive value!!

Question 5

organelles in bacterial cell

Answer 5

• non membrane-bounded organelles
• cell processes are carried out by proteins that float freely in cytoplasm or are embedded in the plasma membrane
• does contain internal membranes similar to chloroplasts and mitochondria

Question 6

structural support in bacterial cell

Answer 6

• Cell wall made of peptidoglycan
• Can have thick wall made of multiple ^ layers
• Or thin wall with an outer layer of lipids
• Bacteria DO possess internal scaffolding of proteins that play role in determining shape, polarity, and other spatial properties of bacterial cells

Question 7

how does diffusion limit cell size in bacteria

Answer 7

• Small cell has more surface area in proportion to its volue
  ○ Interior parts of a small cell are closer to the surrounding environment than those of a larger cell
  
  • So!!! Slowly diffusing molecules do not have to travel far to reach every part of a small cell’s interior
  • As cell size increases, It becomes harder to supply the cell with the materials needed for growth

Question 8

Unicellular

Answer 8

one cell

Question 9

• Multicellular

Answer 9

– billions to trilion of cells that function in a coordinated function

Question 10

Plasma membrane

Answer 10

separates the living material within the cell from the nonliving environment around it
○ Controls movement of materials into and out of the cell

Question 11

Nuclear membrane

Answer 11

selectively controls movement of molecules into and out of it

Question 12

what are the 3 domains of life

Answer 12

○ Bacteria & Archaea
§ Mostly single celled microorganisms
§ Lack nucleus
§ prokaryotes
○ Eukarya
§ Have a nucleus
§ Eukaryotic

Question 13

Organisms acquire energy from 2 sources

Answer 13

○ Sun
Chemical compounds

Question 14

Metabolism

Answer 14

chemical reactions by which cells convert energy from one form to another and build and break down molecules

Question 15

adenosine triphosphate (ATP)

Answer 15

Molecule that carries energy within cells

Question 16

Many metabolic reactions are highly conserved between organisms, meaning…

Answer 16

the same reactions are found in many different organisms

Question 17

internal organization in eukaryotes

Answer 17

• Has a nucleus
• Allows for Transcription and Translation to be separated in time and space
• Allows for more complex ways to regulate gene expression than is possible in prokaryotes
  Has organelles – divides cell contents into smaller spaces specialized for different functions

Question 18

lipids in eukaryotes

Answer 18

Cholesterol (part of the sterol group)

Question 19

lipids in prokaryotes

Answer 19

• Do noy synthesize sterols
  Some synthesize compounds called hopanoids

Question 20

nucleoid

Answer 20

• DNA concentrated in discrete region of cell
  because prokaryotes have no nucleus!!

Question 21

eukaryote internal scaffolding

Answer 21

• rely on these to organize the cell
• different from protein framework of bacteria in that it can be remodelled quickly, enabling cells to change shape!!

Question 22

endomembrand system

Answer 22

are all interconnected, many are capable of changing shape rapidly. are in dynamic continuity!
- dynamic network of membranes
- nuclear envelop
- endoplasmic reticulum
- Golgi apparatus
- plasma membrane

Question 23

endocytosis

Answer 23

engulfing molecules or particles
enabled by cytoskeleton and membrane system

prokaryotic cells cannot perform this activity!!

Question 24

phagocytosis

Answer 24

specific form of endocytosis in which eukaryotic cells surround food particles and package them in vesicles that bud off from the cell memrane

Question 25

exocytosis

Answer 25

molecules or cytoplasmic waste formed within the cell are packaged in vesicles and moved to the cell surface for removal

Question 26

how are intracellular vesicles and the molecules they carry transported?

Answer 26

molecule motors associated with the cytoskeleton!!

the speed means that EUK cells can be larger than most bacteria

Question 27

mitochondrion

Answer 27

where aerobic respiration

Question 28

chloroplast

Answer 28

where photosynthesis