Subcellular Architecture of the Eukaryotic cell and Protists

Question 1

what are the four major roles that membranes play in the cell?

Answer 1

1. restricts movement in and out of the cell
2. prevents organelles from mixing with the cytoplasm
3. regulating the transport of molecules in and out of the cell
4. receiving signals from the environment

Question 2

define selective permeability

Answer 2

some substances can pass through the lipid portion of the membrane without transport protein

Question 3

what are free ribosomes?

Answer 3

ribosomes that float freely in the cytoplasm and make proteins that are used within the cell

Question 4

what are bound ribosomes?

Answer 4

ribosomes bound to the rough endoplasmic reticulum
- they also produce proteins that go outside the cell or are used within the cell membrane

Question 5

what is the purpose of the mitochondria?

Answer 5

it is responsible for converting the energy in food molecules into energy in the form of ATP

Question 6

what is the endomembrane system?

Answer 6

where protein production and modification take place

Question 7

what is the function of a lysosome?

Answer 7

the breakdown of materials in the cell

Question 8

what is endosymbiosis?

Answer 8

where one organism began living within the body of another

Question 9

what is the evidence that the endosymbiotic theory that chloroplasts and mitochondria came from two prokaryotes living in each other?

Answer 9

mitochondria and chloroplasts reproduce like binary fission and have very similar structure to bacteria

Question 10

explain the path of proteins that stay inside the cell

Answer 10

1. in the nucleus the DNA creates mRNA through transcription
2. the RNA goes to a free ribosome
3. then the ribosome goes through translation and stays in the cell
   (All of this takes place inside the cytoplasm)

Question 11

explain the path of proteins that are exported outside of the cell

Answer 11

1. DNA creates mRNA through transcription
2. the RNA goes to a free ribosome
3. the RNA goes to bound ribosome
4. protein is produced in rough ER, or sent to the lysosomes
5. the RNA travels to the golgi apparatus where they are labeled/given their function based on sugars placed on them
6. then a transport/secretory vesicles transports the protein to outside the cell, through the cell membrane

Question 12

describe the basic characteristics of protists

Answer 12

• eukaryotic
• most are unicellular
• membrane bound nuclei and organelles
• they range metabolically from photoautotroph to heterotrophy - not photoheterotrophs
• occupy marine, freshwater, and terrestrial environments

Question 13

what are apicomplexians?

Answer 13

parasites, specialized for living and reproducing inside animal cells

Question 14

define convergent evolution

Answer 14

when unrelated organisms in the same environment evolve similar functional traits