Anatomy of the Cell - Lecture 1 Flashcards
What are the features of common to all eukaryotic cells.
Cellular Membrane Cytosol Cytoskeleton Membrane Bound Organelles Inclusion
What is the Cytosol?
A solution of proteins and electrolytes and carbohydrates
What does the cytoskeleton consists of?
- Thin filaments
- Intermediate filament
- Microtubules
What is the purpose of the Cytoskeleton?
Determines the shape and fluidity of the cell.
What is the Plasmalemma?
The Cell Membrane
Describe the polarity of the Membrane?
It is amphipathic phospholipid bilayer
What is the arrangement of the phospholipids in the bilayer?
The hydrophilic heads are on the outer region.
The hydrophobic fatty acid chains face towards the middle of the two layers
What do embedded protein act as in the Membrane?
- Receptor channels
- Transporters
- Enzymes
- Cell attachment proteins
What is the membrane considered (e.g. solid, liquid, gas) ?
The cell membrane is a fluid
It can change it shape easily
Membrane proteins can diffuse laterally in the cell.
What is the membrane highly permeable to?
- Water
- Oxygen
- Small hydrophobic molecules
What is the function of the Mitochondria?
Energy production
What is the function of the Rough Endoplasmic Reticulum?
Protein Synthesis
What is the function of the Smooth Endoplasmic reticulum?
Cholesterol/lipid synthesis and detoxification
What is the function of the Golgi Apparatus?
Modification and packaging
What are the functions of Lysosomes?
Hydrolytic enzyme for intracellular digestion
What is the function of the Nucleus?
Genetic Code stored here
What are Microfilaments made from?
Composed of Actin
What is the structure of Intermediate Filaments?
6 main proteins
What is the function of Intermediate filaments?
- Bind to the plasmalemma
* Used for structure
What are Microtubules composed of?
Compose of two tubulin proteins
Where do Microtubules originate from?
The centrosome
What is the function of the Microtubules ?
Serve as a motorway to transport material with the aid of dynein and kinesin.
What is Kinesin?
Kinesin is an ATPase that moves towards the cell membrane
What is Dynein?
Dynein is an ATPase that moves towards cell centre.
What is continuous with the endoplasmic reticulum?
Perinuclear Cistern
What is Euchromatin?
Euchromatin - DNA that is actively undergoing transcription.
What is Heterochromatin?
Heterochromatin, DNA condensed and not undergoing transcription.
Where are Ribosomes formed?
The Nucleolus
Describe Protein synthesis in the R.E.R?
- Free ribosome attaches to mRNA
- If ER signal sequence is present growing peptide is inserted into a pore in the ER
- Growing peptide forms in the ER
- Ribosomes detaches (most proteins then enter SER)
What is the purpose of the Golgi Apparatus?
Modification and packaging of the macromolecules
What is the function of the S.E.R ?
Important role in the synthesis of lipids
What face do vesicles arrive on the golgi?
The Cis Fce
What face do the Vesicles leave the golgi from?
The Trans face
What is the function of the Mitochondria?
Generation of ATP
Synthesis of Lipids
Play a role in cell death
What are the types of Intracellular junctions?
Occulding Junctions
Anchoring Junctions
Communicating Junctions
What is the fucntion of an Occulding Junction?
Links cell together to form a diffusion barrier
Where are Occudling junctions found?
Focal regions of close apposition between cells
What are the functions of Anchoring Junctions ?
Provide Mechanical strength
What are the three types of anchoring junctions?
Adherent Junctions
Desmosomes
Hemi-Desmosomes
What is the function of a Communicating Junction?
Allow movement of ions between cells
-Found in smooth muscle/cardiac muscle
