Muscle and Nervous Tissue

Question 1

Describe a Muscle tissue

Answer 1

-it is specialized for contraction

-generates force to produce motion of body parts
-moves substances through blood vessels and organs

-maintains body temperature

Question 2

Describe nervous tissue

Answer 2

-receives, processes and integrates signals from within the body and from the external environment

-generates and transmits impulses that control and integrate the various functions of the body

Question 3

What are the characteristics of the muscle tissue

Answer 3

-elongated cells(longer than wide)

-specialized to contract(myofilaments: actin and myosin)
->generates force

Question 4

What are the different types of muscle tissue

Answer 4

1. Skeletal Muscle
   -cylindrical, with multiple peripheral nuclei
   -striated
   -powerful contractions but fatigued easily
   -attaches to bone: voluntary contractions through somatory innervation
2. Cardiac Muscle
   -striated
   -single central nucleus, branching fibres with intercalated disks
   -specialized for continuous and rhythmic beating
   -involuntary contractions(autonomic innervation)
3. Smooth Muscle
   -spindle-shaped with a central nucleus
   -non-striated
   ->not arranged in an organized banding pattern
   -slow sustained contractions(associated with viscera or organs)
   -involuntary contractions

Question 5

Are skeletal muscles wrapped in 3 connective tissue layers?

Answer 5

-yes

-these connective tissues:
->binds muscle together
->seperates muscle compartments
->transmits the force of contractions to the muscle attachment

Question 6

What are the layers surrounding the muscle

Answer 6

-endomysium(surrounds individual muscle cells)
-perimysium(surrounds group of fibres(fascicles)
-epimysium(surrounds entire muscle(continuous with tendons)

Question 7

Define a muscle cell

Answer 7

-skeletal muscle fibre formed by fusion of many myoblasts

Question 8

What is each sarcoplasm of muscle cells filled with

Answer 8

-it is filled with myofibrils(myofilaments:actin and myosin) which are eosinophilic(stains red and pink)

-organelles are found between myofibrils

Question 9

Are cardiac muscle heavily striated

Answer 9

-not as heavily striated as skeletal muscles
-contractile myofilaments work similarly to the skeletal muscles

-cardiac muscles fibres are also surrounded by connective tissue endomysium with many capillaries

Question 10

What is a major component of cardiac muscles(hint it has to do with disks)

Answer 10

-intercalated disks

-they are complex, intercellular junctions between the ends of adjacent cardiac muscle fibres

-composed of interdigitating plasma membranes of adjacent fibres

-communicating cell junctions
->allows for ionic coupling between fibres via gap junctions

Question 11

Describe smooth muscle

Answer 11

-non-striated, spindle shaped muscle fibres
-they are tightly interlaced with centrally located and oval shaped nuclei

-very little connective tissue compared to cardiac and skeletal muscle

-there are no myofibrils

-autonomic nerves and capillaries can be found in the surrounding connective tissue

-non-contractile organelles are located at the poles of the nucleus

Question 12

Is skeletal muscle much larger than smooth muscle

Answer 12

-yes

Question 13

Are neurons asymmetrical

Answer 13

-yes
->with long cytoplasmic processes
->there are 4 functional compartments: cell body, dendrites, axons, presynaptic terminals

Question 14

What is the purpose of small glial cells

Answer 14

-they support in metabolism and structure and protect and provide framework for neurons

Question 15

Are cell bodies really dark when stained

Answer 15

-yes
->because where most of the metabolic processes occur

Question 16

What covers one axon, one bundle and the entire nerve

Answer 16

-endoneurium is the connective tissue over a nerve axon

-perineurium is a connective tissue over a fascile or a nerve bundle

-epineurium is a connective tissue over an entire nerve