2 - Cell Structure and Organelles Flashcards
Who discovered cells and in what year?
Robert Hooke - 1665
What is Cell Theory and when was it introduced?
1839
- All living organisms are made of cells.
- Cells are the basic unit of life.
- Cells arise from pre-existing cells.
What are the basic requirements of a cell?
- Cell Membrane
- DNA
- Energy Metabolism
What is the function of the phospholipid bilayer?
Permeable Barrier,
Regulated Transport,
Communication with environment.
What is ATP?
Chemical energy used by the cell.
What is the difference between a prokaryotic and eukaryotic cell?
Prokaryotic has free DNA (Nucleoid) can have flagellum eg. bacteria/archaea.
Eukaryotic is an animal cell with DNA in nucleus and organelles.
What are the 4 groups of Archaea?
- Methanogenes (methan producers)
- Thermoacidophils (heat and acid lovers)
- Chemosynthesizers (make own chemicals)
- Extreme Halophiles (salt lovers)
What is the difference with Archaea cell wall?
Monolayer not bilayer. Ether linkage, branched hydrocarbon.
What is Cytoplasm?
Fluid inside plasma membrane (cytosol).
Contains Organelles.
What are organelles?
Absent from prokaryotic cells.
Perform specialised functions.
What is a protist?
Mostly unicellular and live in colonies.
Mostly asexual
Typically water based environments.
eg Slime Mold, Water Mold.
What is the function of the nucleus?
Stores DNA
Codes for protein synthesis.
What is the nuclear envelope?
Double membrane layer around nucleus.
Pores to regulate the transportation of molecules.
DNA+Packaging proteins = Chromatin.
Prokaryotic vs Eukaryotic chromosomes
PROKARYOTE
• A circular DNA molecule
• No associated proteins
• 1 chromosome only
EUKARYOTE
• A linear DNA molecule
• Associated with histone proteins
• 2 or more different chromosomes
What is Nucleolus
- Assembly of ribosomes begins here
* Produces ribosomal RNA (rRNA)
What is Transcription and Translation
Transcription is DNA to RNA.
Translation is RNA to Protein
What are Ribosomes
Ribosomes (protein factories)
• Composed of ribosomal RNA and proteins
• Function: produce proteins
• Location: in nucleus, cytoplasm, rough endoplasmic reticulum
What is Endoplasmic reticulum (ER)
Endoplasmic reticulum (ER)
• Function: transport of materials
• Location: from nuclear envelope to cell membrane
What is Rough ER
Rough ER
•
Surface appears “rough” = many ribosomes attached
•
Receives newly synthesised proteins, modifies them, helps transporting them
•
Makes most membrane bound proteins
What is Smooth ER
Smooth ER
- No ribosomes
- Modifies proteins from the RER
- Detox
- Glycogen degradation
- Synthesis of lipids and steroids
- Stores Calcium (eg. muscle function)
What is Golgi Body
Location: near RER & Nucleus Function: shipping and receiving. •Receives proteins from RER (vesicles) •Modifies/sorts proteins •Adds carbohydrates •Synthesizes polysaccharides for plant wall.
What are Vacuoles
Vacuoles (sac-like structures in cytoplasm; storage)
- Function:
- Storage of water, salts, proteins, carbohydrates
- Remove excess water from cell (contractile vacuole)
- Arise from ER and Golgi
What are Lysosomes
Lysosomes (digestive compartments)
Function:
•filled with enzymes; breakdown of lipids, carbohydrates, proteins from food
•cell cleaner: break down of old organelles, dead pathogens
Arise from the Golgi body
•After breakdown the building blocks
will be released into the cytoplasm
What are Peroxisomes
Peroxisomes (Security and waste removal)
•Function:lipiddestruction; containsoxidativeenzymes
