a&p exam 2

6. List the types of sudoriferous glands and compare their functions.

- merocrine (many places in body), apocrine (few, puberty, groin/armpit, smelly)

Which of the following phrases best describes the cyclical actions of a myosin cross-bridge during a muscle contraction? [Learning Outcome: 7-3, Level 2]

"attach, pivot, detach, and return"

Perforating (Volkmann's) canals

At right angles to the central canal Connects blood vessels and nerves of the periosteum and central canal - provide passageways for linking the blood vessels of the central canals with those of the periosteum and the marrow cavity.

hermatoma

Blood-filled swelling caused when blood vessels are ruptured when the bone breaks (blood clot)

Which of the following statements correctly defines tension? [Learning Outcome: 7-5, Level 1]

It is an active force applied to an object that tends to pull the object toward the source of the force.

keratin vs carotene

Keratin- tough, fiborous _proteins_ found in the skin, nails, and hair Carotene- orange-yellow _pigment_

spongy bone

Layer of bone tissue that has many small spaces and is found just inside the layer of compact bone.

synchondrosis

an almost immovable joint between bones bound by a layer of cartilage, as in the vertebrae.

intercalated discs

are specialized sites of contact between cardiac muscle cells

Which of the following is an example of a synchondrosis?

articulation between the diaphysis and epiphysis in a growing long bone

What 3 cells does the stratum basale layer have?

basal (dividing & making more skin cells), merkel (pressure cells), melanocytes (make melanin)

In response to action potentials arriving from the transverse tubules, the sarcoplasmic reticulum releases...

calcium ions

Which of the following accounts for almost two-thirds of the mass of bone tissue?

calcium phosphate

sebaceous gland

holocrine secretion

apocrine secretion

mammary gland

sudiriferous gland

merocrine secretion

epiphyseal line

remnant of the epiphyseal plate, seen in adult bones

muscle agonist

the contracting muscle that initiates movement

What is the source of most of the calcium ions that enter smooth muscle cells to trigger contractions? [Level 1]

the extracellular fluid (NOT sarcoplasmic reticulum bc no sarcomeres in smooth muscle!)

The heart has to be able to regulate its contractions. Heart muscle, unlike skeletal muscle, cannot go into a tetanus. This is because

the heart muscle has to be able to consistently contract and pump blood in a controlled fashion.

neuromuscular junction

the junction between a nerve fiber and the muscle it supplies

undulate

to move in waves

What is the function of the transverse tubule?

to transmit electrical impulses to the cell's interior

Tropomyosin strands are held in position by which of the following?

troponin molecules

origin

attachment of a muscle that remains relatively fixed during muscular contraction

stratum spinosum (spiny layer)

cells arranged in 8 to 10 layers with desmosomes that pull cells into spiny shapes; rich in RNA

compact bone

dense, hard layers of bone tissue that lie underneath the periosteum

sarcolemma

plasma membrane of a muscle fiber

epiphyses

proximal and distal ends of the bone

Melanosomes

store melanin

What epidermal layer is characterized by cells that have stopped dividing and have begun making large amounts of keratin?

stratum granulosum

Which layer is only found in thick skin?

stratum lucidum

5. Describe the papillary and reticular layers of the dermis. Draw and label a diagram of the layers of the dermis.

- papillary has blood vessels (capillaries), lymphatic vessels, and nerves - reticular is a network of collagen & elastic fibers The papillary layer of the dermis contains blood vessels, lymphatic vessels, and sensory nerves. This layer supports and nourishes the overlying epidermis. The reticular layer consists of a meshwork of collagen and elastic fibers oriented to resist tension in the skin.

functions of skeletal muscle

- produce bone movement - maintain body posture - maintain body temp

fracture repair steps

1. hematoma (blood clot) forms 2. fibrocartilage and collagen (soft callus) fill in space 3. Osteoblasts convert fibrocartilage into spongy bone (bony callus) 4. osteoclasts remodel bone by reabsorption

periosteum and endosteum

A long bone is covered externally with a sheath called ______________, whereas the marrow/medullary cavity is lined with _____________.

sarcoplasmic reticulum (SR)

A specialized endoplasmic reticulum that regulates the calcium concentration in the cytosol of muscle cells.

What is the main difference between spongy bone and compact bone?

Compact bones contain osteons; spongy bones contain trabeculae.

Canaliculi

Hairlike canals that connect lacunae to each other and the central canal

papillary layer function

Nourishes and supports epidermis, fingerprints

Which of the following is true about red muscles?

Red muscles are slower than white muscles. (also... don't fatigue quickly)

Which of the following is an accurate characteristic of slow fibers?

Resting slow muscle fibers contain oxygen reserves, bound to myoglobin.

Try to come up with some advantages of the avascularity of epithelium and cartilage. Also, try to deduce why tendons are poorly vascularized.

Simple epithelium is thinner than the diameter of the smallest vessel and must overlie all other tissues. Stratified epithelium forms the protective covering of deeper tissues. If blood vessels were within the epithelial layer, protection of the vessels would be reduced. Cartilage undergoes severe compression, which could damage vessels. Tendons are designed to withstand a strong pull; vessels would weaken the structure of tendons and would be at risk for rupture during extreme tension.

insertion

The attachment of a muscle tendon to a moveable bone or the end opposite the origin

In terms of both function and benefit, why are surface keratinocytes dead?

The stratum corneum is so far removed from the underlying blood supply in the dermis that diffusion of nutrients is insufficient to keep the cells alive. Also, the accumulation of glycolipids in the intercellular spaces retards diffusion of water-soluble nutrients. The accumulated keratin within the cells inhabits life functions. In terms of benefit, bacterial or other infections cannot become established easy in the deaf, water-insoluble layer. Dead cells provide a much more effective mechanical barrier than living cells (from water loss and infections).

Which of the following statements concerning slow fibers is NOT true? [Learning Outcome: 7-7, Level 2]

They contain large glycogen reserves.

cyanosis

a bluish discoloration of the skin resulting from poor circulation or inadequate oxygenation of the blood.

7. Explain what causes skin pigmentation and why there are differences.

carotene (orange) & melanin (brown), and oxygen saturation (blood supply), ex: cyanosis

medullary cavity

cavity within the shaft of the long bones filled with bone marrow

Melanocytes

cells that produce melanin to protect against UV rays

synergist

muscle that aids a prime mover in a movement and helps prevent rotation

fixator

muscle that prevents movement of bone

muscle antagonist

muscles opposite or opposing the agonist (opposing muscles)

muscle action

named for action they produce, e.g., flexor or extensor

The less-movable end of a skeletal muscle is the

origin

Lamellae (compact bone)

rings of bone matrix within an osteon

merocrine secretion

salivary & sweat glands

holocrine gland

sebaceous gland

diaphysis

shaft of long bone, composed of compact bone

Lacunae (compact bone)

small cavities in bone that contain osteocytes

callus formation

soft callus of fibrocartilage replaced by hard callus of bone in 6 weeks

T-tubules (transverse tubules)

spread the action potential into the interior of the muscle fiber

Describe the main structures of the epidermis, and explain the functional significance of each.

(Boy Stop Going Loco Crazy, deep --> superficial) - basale (stem/basale cells), spinosum (still dividing, white blood cells), granulosum (make keratin & stop dividing), lucidum (clear), corneum (15-20 layers of flat cells)

4. Describe the overall structure of the skin. Draw and label a diagram showing the epidermis and dermis.

- 3 layers (epidermis, dermis, hypodermis) - dermis split into papillary and reticular - hypodermis has adipocytes (fat cells) - subcutaneous layer under

11. Compare skeletal, cardiac, and smooth muscle tissue with respect to: location, function, and structure.

- cardiac muscles are different than skeletal muscle bc they're smaller, have a single nucleus, rely on aerobic metabolism, and have intercalated discs - cardiac have automaticity (don't require neural stimulation to contract) --> contractions last longer than skeletal, and cannot undergo tetanus - smooth muscle is nonstriated, involuntary, and can contract over a greater RANGE of lengths than skeletal - smooth muscle lack direct connections to motor neurons

1. Draw, label, and describe the gross structure of a long bone including the location and structure of: a) compact bone b) spongy bone c) diaphysis d) epiphyses e) epiphyseal line f) medullary cavity g) periosteum h) endosteum

- epiphysises at both ends - epiphyseal line: when someone stops growing, it replaces the cartilage - medullary cavity - endosteum on the inside - periosteum on the outside

Which of the following structures surrounds each skeletal muscle fiber and ties adjacent muscle fibers together? [Learning Outcome: 7-2, Level 1]

endomysium

Which muscle functions in abduction of the wrist? [Learning Outcome: 7-11, Level 1]

flexor carpi radialis

3. Describe the process of fracture repair.

fracture hermatoma formation (blood clot) --> fibrocartiliginous callus formation --> spongy bone formation (bony callus) --> compact bone formation (bone remodeling)

Unlike skeletal muscle tissue, smooth muscle tissue __________.

is involuntary, lacks sarcomeres, and is not striated