HTHSCI 1H06A- EXAM lessons 13-25

What do the quadriceps muscles work together to form?

Tendon for the patella to be inserted

Where do the quadriceps muscles insert?

Tibial tuberosity in front of the patella

What are the 4 muscles of the quadriceps?

-rectus femoris
-vastus lateralis
-vastus intermedius
-vastus medialis

Where does the semi-membranosus tendon insert?

Medial aspect of tibial plateau

Where does the semi-tendinosus tendon insert?

Medial aspect of tibial plateau

Where is the popliteal fossa?

posterior knee joint

Where do muscles of balance from the thigh insert and what do they contribute to?

Medial aspect of the tibia, form the pes anserinus

What is the name for the bursa between tendons and the condyle of the femur?

Pes anserine bursa

What does the adductor hiatus allow for?

Femoral to get to back of knee and form politeal artery

Is the PCL or ACL bigger?

PCL

What is the purpose of a synovial membrane around the articular surface of the femoral condyles?

To exclude cruciate ligaments (intra-capsular but extra-synovial)

What does the medial meniscus do?

Improves fit between the femur and tibial plateau

What does "unlocking the knee" result in?

External rotation of the femur

How are the tibia and fibula attached?

Interosseus membrane

What artery is able to pass through the interosseus membrane?

Anterior tibial artery

What is a typical ACL injury?

Rotation from the foot being glued to the floor

What are 2 typical PCL injuries?

hyperextension of knee
blow to tibial tuberosity

What does the ability to "open the drawer" indicate?

ACL damage

What does the ability to "close the drawer" indicate?

PCL damage

What is the "unhappy triad"?

ACL, MCL, medial meniscus - blow to the lateral femur
What makes up the triceps (plantar flexors) group? What do they form?

What innervates the plantar flexors?

Tibial nerve

What do the deep muscles of the plantar flexors have an action on?

Toes

What do the tendons of the deep muscles cross?

Medial malleolus

Where do the deep muscles attach? Why?

Tarsal bones on medial aspect to get inversion

What are the 3 deep plantar flexor muscles?

-Tibialis posterior
-Digital flexors
-Hallucis muscle

What does the flexor digitorum do?

Sends tendons out to toes

What does "Tom, Dick, and not Harry" stand for?

-Tibialis posterior
-Digital flexors
-Artery (posterior tibial)
-Nerve (tibial)
-Hallucis (longus muscle)

What are the dorsiflexors responsible for?

Extension of the toes, eversion of the foot

What innervates the dorsiflexors?

Fibular nerve

What do the tibialis anterior and posterior work together to do?

Inversion

What do the digital extensors do?

Extend toes

What does the fibularis group do?

Eversion of toes, plantar flexion of foot

What does the tibial nerve innervate?

Intrinsic muscles of plantar compartment of foot (deep, posterior)

What compartment does the fibular nerve innervate?

Anterolateral

What would you have difficulty doing if you were to knock out the fibular nerve?

Dorsiflexion, eversion, toe extension

What does the popliteal artery divide into?

anterior and posterior tibial arteries

What are causes of pain in the anterolateral compartment? (3)

-microfractures
-strains (muscles tear away from interosseus membrane)
-poor blood flow (lactic acid buildup)

What does the posterior tibio-fibular ligament do?

Keeps fibula and tibia together

What makes up the "functional mortise"?

Talus, fibula, tibia

How is the talus jammed into the tibia and fibula in dorsiflexion?

Wider part jammed = really stable

How is the talus jammed into the tibia and fibula in plantar flexion?

Loose = much less stable

Where is the deltoid ligament found?

Medial aspect of ankle

What are the lateral ligaments that stabilize the ankle joint?

-anterior talo-fibular
-posterior talo-fibular
-calcaneo-fibular

How susceptible are lateral ligaments to injury and what usually occurs?

all very tiny and susceptible to injury, usually inversion sprains in the least stable position (plantar flexion)

How is the weight distributed across the foot?

Equally distributed between posterior (calcaneus) and anterior (towards metatarsals)

What do the longitudinal and transverse arches have?

Spring-like property

What ligaments and tendons help maintain the longitudinal arch? (3)

-calcaneo-navicular ligament
-peroneus longus muscle (fibularis tendon)
-tibialis posterior muscle

What innervates the intrinsic muscles of the foot? (plantar surface)

tibial nerve

How does the endocrine system broadcast hormonal messages all over the body?

Producing hormones in one part of the body that circulate through the whole body (hypothalamus --> bloodstream)

How is the endocrine system long acting?

Endocrine hormones last minutes to days while neurotransmitters work from fractions of seconds to minutes

How is the endocrine slow to act?

onset of action of hormone is seconds to minutes which is much slower than neurotransmitters that can take only milliseconds

How are endocrine hormones blood borne?

Released by the "ductless glands" throughout the body into the bloodstream

How are endocrine hormones also neurotransmitters?

Epinephrine and norepinephrine can cross synapse and act as neurotransmitters but may be released into the bloodstream by the adrenal medulla

What are examples of how top drug prescriptions are for hormones?

-synthroid (treating hyothyroidism)
-oral contraceptives
-humulin (recombinant insulin for diabetes)
-various cortical steroids (inflammatory disorders)

The hypothalamus works largely through...

The pituitary gland

What does the pineal gland do?

Secretes melatonin to regulate day-night cycle

What does the thyroid gland do?

"Turns up" metabolic activity to every single cell in the body

What does the parathyroid gland do?

Regulates calcium levels to keep muscles contracting and neurons firing (calcitonin + parathyroid hormone)

What do the adrenal glands do?

Release glucocorticoids to regulate blood glucose levels

What does the pancreas release?

Glycogen and glucagon

What endocrine role does adipose tissue have?

Releases a lot of hormone products to control hunger

What does the stomach do?

Sends ghrelin to the hypothalamus to indicate hunger

What does the placenta do?

Temporary endocrine gland that develops during pregnancy and produces large amounts of endocrine substances, particularly sex steroids

What is gigantism due to?

Hypersecretion of growth hormone (GH) after puberty - long bones grow

What is Cushing's Syndrome due to?

Hypersecretion of cortisol (moving fats around in the body and starts to deposit in weird places)

What 2 reasons can diabetes be due to?

Low amounts of insulin or insensitivity to insulin

What is hypothyroidism due to?

Low amount of circulating thyroid hormone

Why did people in the upper class during the Renaissance have goiters?

Less diverse diet, low iodine

How do hydrophilic hormones act?

Cannot cross plasma membrane, must attach to receptor outside of cell

How do lipophilic hormones act?

Endocrine hormone binds to receptor INSIDE the cell

How do paracrine cells act?

Hormone travels to nearby cell and attaches to receptor outside of target cell (E.G. Prostaglandins)

How do autocrine cells act?

Hormone released by cell, stimulates receptor outside cell and acts back on itself (E.G. Insulin)

What does it mean for hydrophilic hormones to be transduced?

Since the hormone binds on the exterior of the cell, the hormone message must be converted to another form within the cell to have any effect within the cell

How common are hydrophilic hormones? What are common examples?

Most common - oxytocin, insulin

What kind of hormone is ADH?

peptide hormone

Why do hormones move in the blood easily?

Because of their water solubility

What does the binding of hormones to cell-surface receptors leads to?

Manufacture of second messengers which alter cellular function

What are examples of second messengers?

cAMP, IP3

What are examples of water soluble hormones that produce second messengers?

Epinephrine and norepinephrine

Why are secondary messengers necessary?

Because plasma membrane is lipid soluble and water soluble hormones cannot diffuse across

How does amplification of a signal occur?

Interaction of a few hormones or neurotransmitters (first messengers) can cause the formation of a lot of second messengers

What is an example of a hydrophilic hormone that can cause direct activation of a cell without second messengers?

Insulin

Where are receptors found for lipophilic hormones?

Intracellular (usually intranuclear as well)

What are examples of lipophilic hormones?

Steroids like estrogen and testosterone, thyroid hormone

How do hormones tend to move in the bloodstream?

Bound to a transport protein

What does the exocrine pancreas secrete?

Digestive proteins

What do endocrine islands of the pancreas secrete?

Blood vessels, a lot of endocrine hormones

What do alpha cells of endocrine islands release?

Glucagon

What do beta cells of the endocrine islands release?

Insulin

What kind of feedback mechanism do many hormones work with?

Negative feedback mechanism

What are types of signals that can lead to hormone release? (3)

-chemical alteration in blood
-nervous
-other hormones

What is an example of chemical alteration in blood?

Ca2+ decrease in blood leads to parathyroid hormone release

What is an example of a nervous signal that leads to hormone release?

pressure on the cervix leads to the release of oxytocin because of sensory neurons which carry the signal

What is an example of how other hormones signal hormone release?

Progesterone and estrogen are released because of luteinizing hormone (LH)

What are the hormones released by the posterior pituitary?

Oxytocin, ADH

What is the difference between anterior and posterior pituitaries?

-Hormones from the posterior pituitary enter the bloodstream directly
-Stimulating hormones from the anterior pituitary travel to the pituitary portal system and then enter the blood, where they stimulate hormone release to the blood

What does growth hormone inhibiting hormone (GHIH) do?

inhibits GH and TSH

What is the structure/location of the pituitary?

Infundibulum hangs off hypothalamus, pituitary hangs off infundibulum

Where does the anterior pituitary arise from?

Outgrowth of ectoderm of the roof of the mouth

What is another name for the anterior pituitary?

Adenohypophysis