BIO 223 Exam 2 Online Q&A

TMCC Dr. Cavanaugh

Bones that are thin and broad are classified as

Flat bones

What part of the bone produces blood cells

Red bone marrow

The bones of the skull are produced through what process

Intramembranous ossification

What is the function of calcium phosphate in bone tissue 

Resist compression 

Cells that secrete the organic component of ECM

Osteoblasts

Bones that experience frequent stress, as when exercising, will experience what type of growth? 

Appositional growth 

Which of the following is NOT a function of the skeletal system

Excretion

Which of the following serves as an opening for blood vessels and/or nerves to pass through a bone 

Meatus 

What type of joint is the least mobile

Synarthrosis

Which type of joint has a fluid-filled cavity between articulating bones

Synovial

The joint between each tooth and its bony socket

Gomphosis

Epiphyseal plates are what type of joint

Sychondrosis

Synovial fluid is secreted by what part of the joint cavity

Synovial membrane

Articular cartilage receives oxygen and nutrients via the

Synovial fluid

A ______ is made of dense regular connective tissue and connects one bone to another

Ligament

What is the functional classification of a hinge joint

Monoaxial

What type of motion occurs between the intercarpal joints 

Gliding 

Movement that decreases the angle between articulating bones 

Flexion 

Movement that brings the body part towards the midline of the body

Adduction

Shaking your head no is an example of what type of movement

Rotation

Movement of the thumb across the palmar surface of the hand is what type of movement

Opposition

Dumping a cup of water down the drain requires which special movement of the forearm

Pronation 

Cells that dissolve extracellular matrix of bone tissue 

Osteoclasts 

Which of the following is NOT a function of the periosteum

Deposition of calcium salts in bone tissue

How many ossification centers are present in intramembranous ossification

Many

Flat bones are formed through what process

Intramembranous ossification

What type of joint forms when two bones fully fuse, as in the coxa?

Syntosis

Which of the following properties is unique to muscle cells

Contractility

The organelles found in muscle cells that facilitate contraction

Myofibrils

Deep inward extensions of the sarcolemma

Transverse tubules

Myofilaments composed of actin, tropomyosin, and troponin

Thin filaments

Groups of overlapping thick and thin filaments that arranged end to end within each myofibril

Sarcomere

The change difference that exist across a plasma membrane due to the difference in the concentration of certain ions on either side of the membrane

Membrane potential

The resting state of ion concentrations is created/maintained by the

Sodium-potassium pump

Ion channels that open and close in response to changes in the charge across the membrane

Voltage gated

Which of the following is rapid source of energy for muscle cells 

Both creatine phosphate and glucose metabolism via glycolysis 

Contraction of a single muscle fiber

Fused tetanus

Period of myogram during which the action potential is first spreading across

Latent period

Stimulating a muscle fiber frequently enough that tension stays constant at nearly 100% of maximum results in what condition

Fused tetanus

Muscles requiring fine motor control will have

Small motor unit

A baseline level of involuntary activation of motor unit

Muscle tone

Picking a book up off a table requires _____ contraction, but continuing to hold it up in one position requires _____ contraction 

Isotonic concentric; isometric 

Each individual muscle cell is surrounded by a thin layer of connective tissue called

Endomysium

Bones that form within a tendon are called

Sesamoid

Which of the following is rough projection where a muscle attaches to a bone

Tubercle, trochanter, tuberosity. (ALL CHOICES)

Bones joined by an interosseous membrane, such as the one between the radius and ulna, have what type of joint

Syndesmosis, amphiarthrotic

What happenes. tothe lactate produced during muscle contraction

It is removed by the blood and converted back into pyruvate by the liver

An overstretched muscle can generate _____ force than a muscle at its normal resting length

Less

As lactic acid and/or CO2 build uo in a muscle fiber, the fiber will fatigue due to

Low pH affecting the ability of calcium to bind appropriately

What is required for muscle relaxation

Acetylcholineesterase to degrade the acetycholine in the synaptic cleft. ATP to power calcium pumps so calcium ions are removed from the sarcoplasm. ATP to bind to myosin so it releases actin

What is the first structure that forms at the site of a bone break

Hematoma 

The resting membrane potential of a muscle fiber is approximately 

Negative 

The resting membrane potential of a muscle fiber occurs because there are more ____ ions outside the cell and more _____ inside the cell

Sodium; potassium

During the cross-bridge cycle, myosin heads move into the cocked position when what happens

ATP that is bound to myosin is hydrolized into ADP+P

When a muscle fiber is repeatedly stimulated to contract, what will happen to the tension generated by the muscle fiber

Tension will increase with each repeated stimulation but only up to a point

The name for the phenomenon described in the last question is

Wave summation

Which of the following events is part of the excitation phase of muscle contraction

Acetylcholine is released from the motor neuron

Which of the following events is part of the excitation-contraction coupling phase of muslce contraction

An action potential reaches the T-tubules

Which of the following events is part of the contraction phase of muscle contraction

Calcium ions binds to troponin

Compact bone formation is the _____ step of bone healing

Final

An action potential will begin when what happens 

Sodium-ion channels open 

In the cross-bridge cycle, myosin heads will bind to exposed sites on 

Actin 

Bone deposition occurs whenever _____ actively outpaces _____ activity

Osteoblasts; Osteoclast

Put the following events of muscle contraction in the correct order: 

1. ACH binds to ligand-gated Na+ channels in the motor end plate triggering them to open 

2. Synaptic vesicles release ACH into synaptic cleft 

3. Na+ ions enter the muscle fiber depolarizing the sarcolemma locally 

4. Action potential arrives at motor neuron axon terminal 

4 → 2 → 1→ 3

Put the following events of muscle contraction in the correct order: 

1. Action potential is propagated down the T-tubules 

2. Depolarization of T-tubules causes Ca2+ channels in sarcoplasmic reticulum to open

3. End plate potential triggers nearby voltage-gated Na+ channels to open triggering an action potential 

4. Cytosol is flooded with Ca2+

3 → 1 → 2 → 4 

Put the following events of muscle contraction in the correct order:

1. Active sites of actin are exposed

2. Calcium ion binds to troponin

3. Troponin shifts allowing tropomyosin to move 

2 → 3 → 1 

Put the following events of muscle contraction in the correct order:

1. Myosin head binds to exposed actin active sites 

2. ADP and phosphate detach from the myosin head 

3. Another molecule of ATP binds to the myosin head

4. The myosin head moves back to its resting position pulling the attached actin toward the center of the sarcomere

5. Myosin head moves into the cocked position 

6. Myosin detaches from actin 

7. ATP bound to a myosin head is hydrolyzed 

7,5,1,2,4,3,6

what type of muscle fiber relies primarily on oxidative metabolism

Slow-twich

What type of muscle fiber has a large diameter

Fast-twich

When a bone is healing an internal callus made of _____ forms in the _____

Spongy bone; medullary cavity

Ligand-gated ion channels are involved in ______ an action potential, while voltage- gated channels are involved in _____ an action potential

Generating; propagating

What event must occur in order for myosin to perform the “power stroke” 

ADP + Pi are released from myosin 

What is the “power stroke”

Myosin moving back into the resting position and pulling actin toward the center of the sarcomere 

Put the steps of endochondral ossification into the correct order: Step 1

Hyaline cartilage model of bone produced by chondroblasts

Put the steps of endochondral ossification into the correct order: Step 2

Bony collar of compact bone laid down on outside of diaphysis

Put the steps of endochondral ossification into the correct order: Step 3

Osteoblasts migrate to interior of diaphysis and begin building spongy bone at primary ossification center

Put the steps of endochondral ossification into the correct order: Step 4

Osteoclasts hollow out medullary cavity

Put the steps of endochondral ossification into the correct order: Step 5 

Osteoblasts migrate to interior of epiphyses and begin building spongy bone of secondary ossification centers

What type of muscle fiber generates long, sustained contractions with relatively low force

Slow-twitch

When a bone is healing, an external callus made of ____ forms in the _____

Cartilage; space beneath the periosteum