Cells Flashcards
List the organelles found in all eukaryotic cells
- Cell surface (plasma) membrane
- Cytoplasm
- Smooth endoplasmic reticulum
- Rough endoplasmic reticulum
- Golgi apparatus + vesicle
- Nucleus (nucleolus + nuclear envelope)
- Ribosomes
- Mitochondrion
List organelles found in animal cells only
- Lysosome
List organelles found in plant and algal cells only
- Chloroplasts
- Vacuole
- Cell wall
- Plasmadesmata
Describe the function of the cell wall
- Maintains cell rigidity
What is the cell wall made of in:
- plants
- algae
- fungi
- prokaryotes
- Cellulose
- Cellulose
- Chitin
- Murein
Describe the function of the cell membrane
- Regulates what can enter and exit the cell
Describe the function of the cytoplasm
- Site of anaerobic respiration
- Where chemical reactions occur
Describe the components and function of the nucleus
- Nuclear envelope, Nucleolus, Chromosomes
- Contains DNA (protein instructions)
- Controls cell activity as it controls transcription
- Pores in envelope control what enters and exits nucleus
- Nucleolus synthesises ribosomes and contains ribosomal DNA
Describe the structure and function of the Golgi apparatus
- Flattened fluid-filled sacs
- Transport, modify, package and sort lipids and proteins
- Labels them so they got to their suited destination
Describe the function of the Golgi vesicle
- Transports modified lipids and proteins to cell surface membrane
Describe the function of the rough endoplasmic reticulum
- Involved in the production of proteinsythesis
- Tubules called cisternae allow for transport of proteins
Describe the function of the rough endoplasmic reticulum
- Involved in the production of proteinsythesis
- Tubules called cisternae allow for transport of proteins
Describe the function of the smooth endoplasmic reticulum
- Involved in the synthesis of lipids
- Processes lipids
Describe the function of the mitochondria
- Site of aerobic respiration
- Produces ATP
- Inner membrane folds to form cristae which increase cell surface area
- Contains matrix which enzymes used in photosynthesis are found
- Has its own ribosomes and DNA to quickly produce proteins
Describe the structure and function of the chloroplast
- Site of photosynthesis
- Thykaloid membranes stack (up to 100) to form grana; grana can be joined by lamelle (flat thin thykaloid)
- Each grana has a chloroplast
- Stroma is weak solution of sugars and salts
- Stage 1 of photosynthesis occurs in grana (chloroplasts)
- Stage 2 of photosynthesis occurs in the stroma
Describe the function of the ribosome and the two types
- Site of protein synthesis
- Either free floating in cytoplasm or attached to RER
- 80S - bigger (25nm radius), found in eukaryotic cells
- 70S - smaller; found in prokaryotic cells, mitochondria and ribosomes
How are cells specialised
- Genes can be turned off
- Genes necessary for cell function are turned on (expressed)
Describe the function of a cell wall (bacterium)
- Made up of murein
- Acts a physical barrier that excludes substances
- Protects against mechanical damage and osmotic lysis
Describe the function of the capsule (bacterium)
- Made of slime
- Protects bacterium from other cells
- Helps group bacteria together for further protection
Describe the function of the cell surface membrane (bacterium)
- Acts as a differentially permeable layer
- Controls entry and exit of chemicals
Describe the function of ribosomes (bacterium)
- 70S - smaller
- Synthesis proteins
Describe the function of Circular DNA (bacterium)
- Holds genetic material
- Processes genetic information for replication
Describe the function of Plasmids (bacterium)
- Can reproduce themselves
- Posses genes necessary to survive adverse environments
- used as vectors in genetic engineering
Describe the function of the flagella (bacterium)
- Lash like
- Propels bacteria
Describe the difference between a gram positive and gram negative cell wall
- Gram-positive cell wall is thick and has multiple layers of peptidoglycan
- Gram-negative cell wall consists of an outer membrane and multiple layers of peptidoglycan
- Gram-negative bacteria are more resistant as their cell wall is impenetrable
List the organelles in a bacterium cell
- Capsule
- Cell wall
- Cell surface membrane
- Ribosomes
- Circular DNA
- Plasmids
- Cytoplasm
- Flagella
Describe the process of binary fission
- Circular DNA replicates - both attach to cell membrane
- Plasmids replicate a variable number of times
- New cell membrane grows and cytoplasm begins to divide
- New cell wall forms - dividing original cell into two daughter cells
- Each daughter cell has one C. DNA but a variable number of plasmids
Describe bacteria’s use in industry
- Replicated in a fermenter - division is rapid
- Cells produced is exponential
- They are sources of enzymes
