Lecture 9: Types of Muscle Flashcards
What type of muscle is this?
SKM
What type of muscle is this?
Cardiac
what type of muscle is this
Smooth
Purpose of Bone morphogenic protein 4(BMP4)
expressed in a gradient format, w/ most expressed in the lateral side
what germ layer is muscle derived from and specifically what is the subdivisions of that layer
Muscles are derived from the Mesoderm Germ Layer
Paraxial mesoderm: forms somites and gives rise to SKM, vertebrae, and dermis
Lateral plate mesoderm: Heart and blood vessels
Somites are regulated by different gradients what are they?
Retinoic Acid: in the cranial end
FGF8/Wnt3a: caudal end
Where are somites located
On either side of the notochord
Somites differentiate into what
Sclerotome: Ventral and medial part of somite detach and migrate to surround neural tube and notochord
Myotome: dorsalmedial and ventrolateral par of the upper somites form muscle cell precursor
Dermatome: cells between the muscle cells and skin
What are myoblast and what to they all do together
Precursor for muscle cell and fuse together to form myotubes which then make myofilaments
Smallest portion of SKM to Largest
or vice versa
What are some features of SKM histologically
Striated, tightly packed and similar shape and size Multinuculated
What is the Triad
T-tubulues and two adjacent cisterns observable in TEM
Myasthenia Gravis
Autoimmune to ACH receptors
Dystrophin
Muscular dystrophies
connects cytoskeleton to the scarcolema
patho w/ progressive muscle weakness
degenerative muscle fiber
Cardiac muscle notice the Intercalated discs which are desmosomes and gap junctions, used for impulses
What is a diad
T-tublues are less organized and associated w/ single terminal cisterns
Smooth muscle cell
