Animal Locomotion

Question 1

3 Types of Skeletons

Answer 1

hydrostatic- fluid inside body, skin on outside keeps fluid under pressure -limited protection because soft body
Exoskeleton- made up of proteins+ polysaccharides that form hard shell -lot of protection but must b shed for growth
Endoskeleton- inside, expose to body fluids -can grow without shedding

Question 2

Ca+ homeostasis

Answer 2

vertebrate skeleton relies on it, blood Ca+ tightly regulated by endocrine negative feedback loops

Question 3

Three types of vertebrate muscle:

Answer 3

Skeletal: moving appendages, voluntary, neurogenic, striated
Cardiac: heart, involuntary, myogenic, striated
Smooth: lining of arteries and veins, involuntary, myogenic, un striated

Question 4

Sarcolemma length

Answer 4

2.5 microns in length, distance shortened per sarcomere is around 0.25 micron, 40000 sarcomeres shorten a muscle by 1 cm

Question 5

Filament Sliding Theory

Answer 5

-explains muscle contractions: due to cross bridge binding between filaments
-actin and myosin are polymers that have responsive bonding sites
-change in myosin shape after cross bridge formation moves filaments past each other

Question 6

What are Reflex Arcs

Answer 6

-stretch receptors and motor neurons connect in CNS, operate “automatically”, important in posture -neural stimulation always shortens skeletal muscles

Question 7

Motor Unit

Answer 7

-one neuron plus all muscle fire it contacts, multiple APs will lead to tetanus (form of summation), produces much more force than a twitch