Producing movement Producing movement Muscle contraction allows
movement Of the body For facial expression To move fluids,
digesting food, and other substances through the body Maintain
blood pressure
Slide 4
Maintaining posture Maintaining posture Muscles are constantly
varying their contraction to maintain posture while we are seated
or standing. Stabilizing joints Muscle contraction helps Muscle
contraction helps keep joints in keep joints in position
position
Slide 5
Generating heat Muscle contraction requires an enormous amount
of energy. When food is converted to ATP to power the muscles,
nearly 75% of the energy is lost to heat. Remember: shivering
functions to raise body temperatures by contracting muscles
Slide 6
Notice the prefixes! -mys, -myo, and -sarco
Slide 7
muscle fiber A single muscle cell is called a muscle fiber.
Muscle fibers are LONG (up to 1 ft). Each muscle fiber is wrapped
in a delicate connective tissue called endomysiumRemember: Endo =
inside
Slide 8
fascicle. Multiple fibers (cells!) are grouped together to form
a fascicle. Each fascicle is wrapped up with a connective tissue
called perimyscium. perimyscium. Remember: Remember: peri = around
peri = around
Slide 9
Blood vessels branch out between the fascicles. The whole
muscle is covered by a thick, tough layer of connective tissue
called epimysium. Epi = outer Epi = outer
Slide 10
to The epimysia fuse to The periosteum (outer connective
tissue) of bone The periosteum (outer connective tissue) of bone -
or - - or - The perichondrium (outer connective tissue)of cartilage
The perichondrium (outer connective tissue)of cartilage - or - - or
- Tendons (rope like connective tissue that connects muscle to
bone) Tendons (rope like connective tissue that connects muscle to
bone) - or - - or - Aponeuroses (sheetlike connective tissue that
attaches muscle to bones, cartilage, or other muscles) Aponeuroses
(sheetlike connective tissue that attaches muscle to bones,
cartilage, or other muscles)
Slide 11
Slide 12
Slide 13
This is a micrograph of muscle tissue, magnified ~70 X
Identify: Nuclei, Muscle fibers, Endomysium Perimysium Blood
vessels
Slide 14
This is a micrograph of muscle tissue, magnified ~70 X
Identify: Nuclei, Muscle fibers, Endomysium Perimysium Blood
vessels
Slide 15
What do you already know about the three types of muscles?
Slide 16
Attached to bones (or, in the face, to skin) Walls of hollow
organs, airways, and arteries Walls of heart
Slide 17
SkeletalSmoothCardiac Regulation of contraction Nervous system
excites contraction. No effect of hormones Nervous system excites
or inhibits contraction. Hormones and other chemicals (e.g. CO 2,
pH, low O 2, ) may stimulate or inhibit contraction. Intrinsic
regulation from a pacemaker within the heart. Natural rhythm can be
excited or inhibited by the nervous system OR by body hormones
Speed of contraction Slow to fastVery slow slow Rhythmic
contraction NoYes, can be triggered by stretch receptors Yes, has
internal pacemaker Muscle contraction is stimulated by nervous
system. Hormones have no effect Contraction can be stimulated
(excited) OR reduced (inhibited) by EITHER the nervous system OR
hormones OR body chemicals (e.g. pH)
Slide 18
Relate at least 3 differences between skeletal, cardiac, and
smooth muscle to differences in their function.
Slide 19
Make a Venn Diagram comparing and contrasting skeletal, smooth,
and cardiac muscle
Slide 20
1) The connective tissue covering that encloses the sarcolemma
of an individual muscle fiber is called the a) Epimysium b)
Perimysium c) Endomysium d) periosteum
Slide 21
2) A fascicle is a) A muscle b) A bundle of muscle fibers c) A
bundle of myofibrils d) A group of myofilaments
Slide 22
3) Muscle tissue that is involuntary a) cardiac muscle only b)
Smooth muscle only c) Skeletal muscle only d) Cardiac and smooth
muscle e) Cardiac and skeletal muscle
Slide 23
4) The muscle tissue that consists of single, very long,
cylindrical, multinucleate cells with very obvious striations is:
a) cardiac muscle only b) Smooth muscle only c) Skeletal muscle
only d) Cardiac and smooth muscle e) Cardiac and skeletal
muscle
Slide 24
5) Which of the following is NOT a function of the muscular
system a) Producing movement b) Maintaining posture c) Stabilizing
joints d) Generating heat e) hematopoiesis