2 - Cells Flashcards
Cells, tissues, membranes, development
Cell membrane
Controls what enters and exits the cell Homeostasis
Anchors cytoskeleton
Nucleus
Control centre for cell metabolism and reproduction Stores genetic information
Ribosomes
Protein synthesis
Endoplasmic reticulum
Transports proteins (RER) and lipids (SER)
Golgi apparatus
Folding and packaging of proteins
Lysosomes
Digestion of debris, invaders, metabolites
DDIM
Mitochondria
Energy production; Glucose + Oxygen = ATP
Cytoskeleton
- Microtubules
- Intermediate filaments Microfilaments (actin)
- Supports the cell, determines its shape and mobility
- Vesicles and organelles transport through the cell along microtubules
How do we keep cells together?
Cell adhesion molecules Intercellular junctions • tight junctions • desmosomes /anchoring junctions • gap junctions
tight junctions
Impermeable junctions prevent molecules from passing through the intercellular space
- interlocking junctions protein
- intercellular space
desmosomes /anchoring junctions
Anchoring junctions bund adjacent cells together like a molecular “Velcro”
- intermediate filament (keratin)
- linker proteins (cadherins)
- plaque and intercellular space
gap junctions
Communicating junctions allow ions and small molecules to pass for intercellular communication
- channel between cells (connexons)
- intercellular space
What are the basic tissues?
Epithelium
Connective tissue
Muscle tissue
Nervous tissue
Epithelium
Layer(s) of cells lining a surface
Connective tissue
Defined by the extracellular matrix
Muscle tissue
Can contract in response to electrical signalling
Nervous tissue
Excitable cells that can harness ion movements
Extracellular Matrix (ECM)
Scaffolding that support cell attachment, migration, proliferation, and differentiation
Structural proteins
Proteoglycans: compliance, shock absorption
Elastin: elasticity
Collagen: strength
Adhesive proteins
Bind matrix proteins together, facilitate adhesion of cells to ECM
- fibronectin and laminin
Transporters
Facilitated transport via transporters
Active transport
Ion transporters vs. ion channels
Facilitated transport
Glucose transport
Active transport
Sodium-potassium pump
Co-transport
Sodium-glucose co-transporter