Exam Review (Problems)

Microbiota of skin - Normal Healthy Skin, are there microbes?`

• the microbiota is a collection of microbes that live naturally on the skin

• composition varies on species, individuals, and/or body site

• exposure to varied microbiome is considered a key component in immune regulation

Inner ear

• vestibular organ (balancing organ)

• cochlea (hearing organ)

middle ear

• tympanic bulla

• tympanic membrane

• ossicles: malleus, incus, stapes

external ear

pinna

hair growth cycle

anagen: mitotic growth increases, melanin production increases

catagen

regression phase, caspase activity increases, and kerationcyte apoptosis increases

telogen

resting phase, small dermal papillae, no mitotic activity

dermal mucinosis - what causes it?

too many polymers; genetic defect in hyaluronic acid metabolism - can develop polyps

polymers are made up of proteoglycans and hyaluronan, resist compressive forces

components that provide tensile strength for the skin?

dermis

dermal fibers resist pull/tensile forces (collagen)

dermal polymers resst push/compressive forces

changes in skin with low quality diet?

internal: malnutrition and low EFAs can lead to epidermal lipid deficiency/disturbance resulting in scaling and poor barrier function, dull coat

recruitment of motor units - how is it done?

orderly recruitment - as stimuli increases the task becomes more dfficult

cross bridge cycle - what is it?

contraction cycle - key features are cross bridge formation, power stroke, release, and reload

cross bridge formation?

calcium ions cause troponin to move tropomyosin off binding site and myosin attaches to actin

power stroke

ADP and phosphate are released as myosin is oulled by actin

release (cross bridge cycle)?

ATP binds to myosin head, breaking the cross bridge

reload (cross bridge cycle)?

ATP is hydrolyzed to ADP and phosphate

muscle shortening?

caused by the shortening of the sarcomere during the power stroke

excitation - given numbers how does it affect cross bridge formation?

• 2 calcium pumped into sarcoplasmic reticulum by SERCA per ATP hydrolysis

• 1 ATP hydrolysis per cross bridge cycle

infraspinatus muscle (o, i, i, a)

o: infraspinous fossa

i: greater tubercle

i: suprascapular nerve

a: extend and flex the shoulder

infraspinous bursa

a synovial bursa that protects the insertion of the infraspinatus at the greater tubercle.

burstis is painful and causes the animal to stand with limb abducted at the shoulder to relieve pressure

coffin bone - how does it interface inside of the hoof?

the hoof wall connects to it interdigittion between dermal and epidermal laminae

what forces work cranially and caudally to interface the coffin bone in hoof?

opposing forces:

caudally- deep digittal flexor pulls

cranially- common digital flexor pulls

palmar digital nerve block blocks?

palmar lateral and palmar medial digital nerves

what structure keeps the position of the proximal sesamoids?

interosseus suspensory ligament

with a scapular fracture with the supraglenoid tubercle coming off, what muscle is associated with this injury?

fracture would impact biceps brachii because it originates from supraglenoid tubercle

bicipital tendon sheath and glenohumeral joint in dog, why is it special?

they communicate