Exam 2 Flashcards
List the 3 major types of cytoskeleton proteins
In Eukaryotic cells: microfilaments, intermediate filaments and microtubules
What is meant by the term “extra cellular matrix”?
collection of secreted proteins and carbohydrates found in the extracellular space of all tissues.
Describe the 3 major components of the extracellular matrix?
- Fibrillar proteins: collagens and elastins
- Multiadhesive proteins: fibronectin and laminin
- Hydrophilic proteoglycans: bind water and growth factors
What are the 2 major types of ECM?
- Basal Lamina: separates different tissues
- Stromal ECM: between cells within a tissue
Where are the 2 major types of ECM located?
- Basal Lamina: separates different tissues
- Stromal ECM: between cells within a tissue
Describe what is meant by the term “basal lamina” and describe what it is composed of.
Separates many tissues and often times provides orientational cues.
Example the epithelial sheet which is composed of (from top to bottome) lumen, basal lamina then connective tissue
Describe what is meant by the term “cytoskeleton”?
- Present in all cells providing structure and support.
- Acts as an intracellular ‘highway system’
- Participates in cell locomotion
Provide an example of how two types of connective tissue can have very different structures and functions
- Cartilage= composed of chondrocyte cells, type II collagen, rich in proteoglycans, resists compression due to high water content
- Tendons= fibrous connective tissue connecting muscle to bone, provide tensile strength, type I collagen
Describe at least 3 functions of the cytoskeleton
- provide transport pathway for intracellular molecules
- cellular locomotion
- help provide cell shape
- anchor organelles in place
Describe what a tight junction is and where it might be found
- seal cells together into sheets, forming an impermeable barrier
- found in intestinal epithelium
Describe what a gap junction is and where it might be found
- primary communication junction, protein channel for small molecules to pass. Cell exchange of electromchemical signals
- found in heart tissue and some neuronal structures
Describe what is meant by the term “cell cycle” and provide a diagram that shows its various phases and what happens in them
- Series of phases leading to the division of a cell into 2 identical daughter cells
- Interphase (G2), Prophase, Prometaphase, Metaphase, Anaphase, Telophase
Provide a diagram of mitosis and list 3 reasons why it is a significant process in human health
- slide 38 week 5 Cell Cycle
- circle cycle of Prophase -> Metaphase->Anaphase->Telophase ->G1, S, G2
-understand development and growth, wound healing, cell replacement, regeneration-neurogenesis-olfactory neuron replacement
What happens in Interphase (G2) and what order phase is this? (1-6)
1st phase, centrosomes with centriole pairs, nuclear envelope with nucleolus, chromatin duplicated
-cell growth and DNA duplicates
What happens in Prophase and what order phase is this? (1-6)
2nd phase, early mitotic spindle, centrosome pairs move to ends are asters, centromere = chromosome consisting of 2 sister chromatids
-condensation of chromatin, nucleolus disappears
What happens in Prometaphase and what order phase is this? (1-6)
3rd phase, nuclear envelope disintegrates, asters moved to opposite ends, kinetochore microtubles attach to kinetochore
What happens in Metaphase and what order phase is this? (1-6)
4th phase, chromosomes moved to metaphase plate,
What happens in Anaphase and what order phase is this? (1-6)
5th phase, chromosomes pulled towards poles
What happens inTelophase and what order phase is this? (1-6)
6th last phase, nuclear membrane reforms
What are the 3 major communication systems of the human body?
Nervous, immune and endocrine systems
List 6 steps that are common to all extracellular signaling communication systems
- Synthesis of signal molecule (ligand) 2. release of signal molecule by signal cell 3. transport of signal to target cell 4. binding of signal molecule to specific receptor 5. ligand binding or signal tranduction 6. removal/termination of signal
What is meant by “signaling molecules operate over varying distances”? Provide 2 examples
- Direct Haptic (touch)-mediated signaling= to cells that they are in direct contact with
- Soluble signaling= to itself, nearby cells, cells in a different tissue or organ
What is meant by a ligand/receptor interaction?
ligand is a small molecule that binds to specific molecules on or within a cell called a receptor
Describe 2 types of cellular receptors and how they are different in terms of their role as effectors.
- ligand gated ion channel
- G protein coupled receptor = activates or inhibits enzymes
Describe agonist and antagonist
week 6 slide 17
- agonist drug= effective active site of similar shape to ligand, binds to receptor
- antagonist= no effect, close in shape to active site, blocks receptor, prevents binding