Eukaryotic cells:Animals Flashcards
Features of the nucleus
5
- Nuclear envelope
- Nuclear pores
- Nucleoplasm
- Chromosomes
- Nucleolus/ nucleoli
What is nuclear envelope?
- Double- memrbane surrounding the nucleus.
What are nuclear pores?
- Pores in nuclear envelope: allow large molecules out of nucleus (e.g., mRNA.)
Function of nucleus.
2
1.) Site of replication (of DNA) and transcription (making mRNA.)
2.) Contains genetic material of cell.
What is the nucleoplasm?
- Nucleoplasm: granular, jelly-like material.
What are chromosomes?
- Protein-bound, linear DNA (linear = has two open ends.)
() - extra info for clarification.
What is the nucleolus (nucleoli? )
- Small sphere within nucleoplasm.
- Site of ribosomal RNA production and makes ribosomes.
- One or more in a nucleus.
Two different types of endoplasmic reticulums?
- Rough endoplasmic reticulum
- Smooth endoplasmic reticiulm.
Structure of endoplasmic reticulum.
- Both have folded membranes called cisternae.
- Rough have ribosomes on cisternae.
Function of rough ER.
- Responsible for protein synthesis
- Responsible for packaging protein into vesicles (that can transport protein out of the nucleus.)
Function of smooth ER.
- Site of lipid and carbohydrate synthesis.
- Lipids and carbohydrates can also be stored here.
Structure of golgi apparatus.
- Folded membranes (making cisternae.)
What passes through the golgi apparatus?
- Proteins/ lipids from ER passed through golgi apparatus.
Structure of golgi vesicles.
- Hollow structures that pinch off from cisternae.
Function of golgi apparatus.
5
- Add carbohydrate to proteins to form glycoproteins.
- Produce secretory enzymes
- Secrete carbohydrates
- Transport, modify, store lipids
- Form lysosomes (powerful digestive enzymes are packages into golgi vesicles.)
() - extra info for clarification
Finish sentence
Golgi apparatus …… molecules, allowing them to be accurately sorted and sent to …….. ……..
- Labels
- Correct
- Destinations
What happens once the proteins and lipids have been modified in the golgi apparatus?
- The modified proteins and lipids are transported to golgi vesicles (which are pinched off from cisternae.)
- G Vesicles move to cell surface, fuse with membrane and release contents to outside.
What are lysosomes?
- A membrane-bound organelle.
- Sac of digestive enzymes.
Function of lysosomes (4)
- Hydrolyse material ingested by phagocytic cells (ie. fuse with phagosomes/ release hydrolytic enzymes - MS answer.)
- Completely break down cells after they have died.
- Release enzymes to outside of cell to destroy material.
- Digest worn out organelles for re-use of materials/ chemicals.
() - extra info for clarification
(Hydrolyse = decompose with water.)
Finish the sentence (from SPEC.)
Lysosomes release ……… enzymes.
- Hydrolytic (enzymes that catalyse the hydrolysis of various bonds.)
() - extra info for clarification.
What is it called when lysosomes release enzymes to the outside of the cell?
- Exocytosis.
What is the structure of mitochondria?
- Double membrane
- (Extensions) of inner membrane = cristae
- Fluid- centre is called the “mitochondrial matrix.”
- Loop of mitochondria DNA.
Function of mitochondria.
1.) DNA codes for enzymes needed in respiration.
2.) Site of aerobic respiration
3.) Site of ATP production.
What are the two types of ribosomes? What makes them different? Where can each type be found?
- 80S and 70S.
- 80S (large ribosome found in eukaryotic cells.)
- 70S (smaller ribosome found in prokaryotic cells, mitochondria and chloroplasts.)
What are ribosomes made of?
- Two sub units (refer to diagram in textbook Pg. 71 for guidance.)
- 1 sub unit = ribosomal RNA.
- 1 sub unit = protein.
Function of ribosomes.
- Site of protein synthesis.
True or False
Lysosomes are not membrane-bound organelles.
- False.
- Lysosomes are membrane-bound organelles.
By what process are modified proteins and lipids released from the cell (after the golgi vesicles fuse with cell surface membrane?)
- Exocytosis.
By what process are chemicals transported INto cells?
- Endocytosis.
