Week 2 Flashcards
Describe columnar epithelial cells:
Taller than wide
What do cilia do?
Move material across the surface
What are stereocilia?
Elongated microvilli use for sensation and absorption
Describe apocrine gland:
Secretion accumulate at secreting margins of the cell and the whole margin pinch off and then breaks down.
What are the two components of the nervous system?
1) Central Nervous System
2) Peripheral Nervous System
What are graded potentials?
Change in membrane potential confined to a small region.
Describe microvilli:
Increase surface for absorption and secretion
Describe afferent neurons:
Convery information from tissues and organs to the central nervous system
What are the function of connective tissue:
1) Binds together, support and strengthen other tissues
2) Protect and insulate internal organs
3) Compartmentalize structures
4) Transport substances
5) Stores energy
6) Main source of immune responses.
How do astrocytes form the brain-blood barrier?
By stimulating the formation of tight junctions between the cells that form the capillaries in the CNS.
What are the similarities between K+ and Na+ ion channels?
1) Both have sequences of charged amino acid that change shape in response to a change in the membrane potential
2) Both stay close at negative membrane potential
What are the three types of tissue repair?
1) Labile
2) Stable
3) Permanent
What is an equilibrium potential?
The electrical potential necessary to balance a given ionic concentration gradient across a membrane so that the net flux is zero.
What are the three different types of epithelium according to the number of layers?
1) Simple
2) Pseudostratified
3) Stratified
How do astrocytes sustain neurons metabolically?
By providing glucose and removing ammonia
Describe merocrine gland:
Released via exocytosis from vesicles.
What is summation?
If additional stimuli occur before the graded potential has died away, this can be added to the first.
What are the two majors layes of the skin:
The epidermis and the dermis
Describe transitional epithelium:
The apical cell layers change shape depending upon distention of the organ
Describe the serous tissue membrane:
Simple squamous epithelium called mesothelium, basement membrane and a thin layer of connective tissue. Line cavities not open to the exterior.
Describe oligodendrocytes:
Forms myelin sheats of the CNS neurons.
Describe cuboidal epithelial cells:
About equal in height and width
Describe the main features of cardiac muscle tissue:
Forms the wall of the heart
Cardiomyocites are striated and branching and connected together by a intercalated disc.
Almost completely under involontary control
What are collaterals?
Branched of the axon
What are the 3 components of the neuron?
1) Cell body (soma)
2) Dendrites
3) Axon
What is a membrane potential?
A separation of electrical charges that exists across plasma membranes
What are the two factors that influence neuronal electrical property?
1) concentration gradient of different ions
2) Permeability of the membrane to those ions
How are exocrine glands classified according to their structure?
Unicellular (goblet cells)
Multicellular
What are the two differences between K+ and Na+ ion chanels?
- Voltage-gate Na+ channel respond faster to change
- Voltage gated Na+ channel has an activation gate.
What are the three different types of muscle tissue?
Skeletal muscle tissue
Cardiac muscle tissue
Smooth muscle tissue
Describe permanent tissue repair:
If killed, replaced by a different type of cell. Limited regenerative activity.
What is an intercalated disc?
A large cluster of gap junctions.
What are the functions of epithelial tissue?
1) Protecting underlying structure
2) Acting as a barrier
3) Permitting the passage of substances
4) Secreting substances
5) Absorbing substance
Describe the axon:
A long process that extends from the cell body and carries outgoing signals to target cell.
Describe the movement of kinesin:
It moves from the cell body to the axon terminal (anterograde)
What are the 5 epithelial layers in the epidermis (from bottom to top)
1) Stratum basale
2) Stratum spinosum
3) Stratum granulosum
4) Stratum lucidum
5) Stratum corneum
Describe interneurons:
Connect neurons within the Central Nervous System
Describe efferent neurons:
Convey information away from the central nervou system to effectors.
Describe endocrine glands:
They are in no open contact with the exterior, they have no duct and produce hormones.