bio 101 lecture exam #2

describe how a true rib differs from a false rib

(1-7) are true ribs because they attach to the sternum through coastal cartilage where (8-12) are indirectly and not attached to the sternum and the last two pairs are floating ribs because they lack sternal attachment

name the components of the thoracic cage

-sternum -jugular notch -manubrium -sternal angle -sternal body -xiphoid process

repair of bone fractures

1. hematoma forms 2.fibroartilage callus form 3.the bony callus forms 4.bone remodeling occurs

Which one of the following is the correct sequence of events that correlates to the sequence of events of a nerve impulse?1. the membrane becomes depolarized2. sodium channels open and sodium ions diffuse inward3. the membrane becomes repolarized4. potassium channels open and potassium ions diffuse outward

2, 1, 4, 3

Which of the following causes the release of neurotransmitter molecules?

an electrical signal reaching the terminal bouton

Each complex of central canal and matrix rings in compact bone is known as

an osteon (harvesian system)

Describe briefly the process of bone formation in the fetus, and summarize the events of bone remodeling throughout life.

In embryos skeleton consist primarily of hyaline cartilage, cartilage later becomes bones except bridge of nose, parts of ribs, and the joints.

Which of the following indicates damage to the primary motor area?

Inability to voluntarily move skeletal muscles

Which one of the following is not a criterion generally used in naming muscles?

Method of attachment of the muscle to bone

Which meningeal layer is filled with cerebrospinal fluid (CSF)?

Subarachnoid space

How does the formation of a bony callus assist with the process of bone healing after a fracture?

The bony callus is made of spongy bone, which replaces the fibrocartilage callus.

Saltatory conduction is a faster type of nerve impulse transmission that occurs along myelinated axons. Why is nerve impulse transmission faster in myelinated neurons?

The nerve impulse can jump from one node of Ranvier to the next, speeding the rate of nerve impulse transmission.

While doing "jumping jacks" during an exercise class, your arms and legs move laterally away from the midline of your body. This motion is called ________

abduction

Neurotransmitters are released upon stimulation from a nerve impulse from the ________.

axon terminals of the motor neuron

The presence of an epiphyseal plate indicates that

bone length is increasing

Muscle tissue has the ability to shorten when adequately stimulated, a characteristic known as __

contractility

A person who excels at weight lifting but does NOT do well at running marathons probably has leg muscles containing a large percentage of ________ fibers.

fast twitch

Name the three major structural categories of joints, and compare the amount of movement allowed by each.

fibrous joints-immobile cartilaginous joints-immobile/slighly movable synovial joints-freely movable

What does collagen contribute as a component of bone?

flexibility

Skeletal muscle, as a whole, can generate different amounts of force, and different degrees of shortening, in response to stimuli. What is this concept called?

graded response

discuss the importance of intervertebral discs and spinal curvatures

intervertebral discs cushion the vertebrae and absorb shock while allowing flexibility. curvatures allow us to enter our body weight on the lower limb with min effort

Cerebrospinal fluid _

is continually formed mostly by the choroid plexuses

Leaning against an immovable wall while waiting for a bus is a type of ________.

isometric contraction

subdivisions of appendicular skeleton

limbs ( upper and lower extremities) which includes the shoulder gridles and pelvis

four main classifications of bones

long(femur), short(bones of wrsit and ankles), flat(skull,sternum,ribs), irregular(vertebrae)

The blood-brain barrier is effective against the passage of

metabolic waste such as urea

The state of continuous partial muscle contractions is known as ________.

muscle tone

Which of the following are specialized cells that receive and respond to stimuli?

neurons

What is released by axon terminals into the synaptic cleft to stimulate a muscle to contract?

neurotransmitter

The point of muscle attachment to an immovable or less movable bone is known as the ______

origin

What type of bone cell is primarily active when bone growth occurs?

osteoblasts

When growing bones widen through appositional growth, what cells add bone matrix to the outside of the diaphysis?

osteoblasts

While ________ are involved in bone deposition, ________ are involved in the breakdown of bone tissue.

osteoblasts,osteoclasts

Describe the microscopic structure of compact bone.

osteocytes are are found within the lacunae, the lacunae are arranged in the concentric circles called lamellae around central canals (harvestian system)(rings). Canaliculi radiate outwards the canals. Communication from outside of bone is done through perforating canals.

Mothers who breast-feed their children will lose a percentage of calcium from their bones. Which hormone is responsible for raising blood calcium levels when they drop below homeostatic levels?

parathyroid hormone (PTH)

The ________ is a connective tissue wrapping around fascicles of neuron fibers.

perineurium

The joint that allows us to shake our head "no" must be a ________ joint.

pivot joint

_ is an increase in the number of active motor units that would increase the force developed by a skeletal muscle.

recruitment

The myofibrils of skeletal muscle are organized into units called

sacromeres

The ________ is a saclike membranous network that surrounds each myofibril.

sarcoplasmic reticulum

What organelle wraps and surrounds the myofibril and stores calcium?

sarcoplasmic reticulum

explain how the different curvatures (scoliosis,lordosis, and kyphosis differ from another

scoliosis- sideways curvature of the spine lordosis-exaggerated lumbar curve kyphosis- excessive outward curvature

Which is a ball-and-socket joint?

shoulder and hip joint

Which of the following types of muscle in humans is involved in voluntary body movements?

skeletal

subdivisions of axial skeleton

skull, vertebral column, thoracic cage

In adults, the function of the yellow marrow is to

store adipose tissue

When a person dies, muscles become rigid and fixed in position. This is a condition known as rigor mortis. Rigor mortis occurs because

ATP is not available to release myosin heads from actin filaments.

What is the unstoppable electrical current that travels down the length of the entire surface of a sarcolemma?

Action potential

Which of these neuroglial cells contributes to the structure of the blood-brain barrier?

Astrocytes

What part of the neuron releases vesicles containing neurotransmitters?

Axon terminals

Sally has a brain injury; she knows what she wants to say but can't vocalize the words. The part of her brain that deals with the ability to say words properly is the ______

Broca's area

__ is the property of skeletal muscle whereby an increase in the frequency of action potentials enhances the force developed by the muscle cell.

summation

3 functions of the skeletal system

support(internal framework),protection(organs),allow movement(tendons attached to bones lever movement) and stroage( minerals)

The gap between two communicating neurons is termed

synaptic cleft

Plane, hinge, and pivot joints are examples of

synovial joints

Neurons either conduct action potentials along the length of their axons, or they remain at rest. This statement best describes

the all-or-nothing response

A sarcomere is ________.

the contractile unit between two Z discs

You examine an articulated skeleton in the laboratory and determine the skeleton to be a female since

the distance between the female ischial spines is greater than in a male

describe importance between a male and female pelvis

the female pubic arch is more rounded female sacrum is shorter female pelvis as whole is shallower

A skeletal muscle twitch differs from a tetanic contraction in that ________.

the muscle twitch is a brief and "jerky" movement, while the tetanic contraction is prolonged and continuous

Which of the following statements is true about the excitation-contraction coupling mechanism in skeletal muscle?

Calcium binds to troponin causing a shift in tropomyosin exposing the binding sites on actin for myosin.

Explain the role of bone salts and the organic matrix in making bone both hard and flexible.

Calcium deposited in the matrix give bone hardness and organic parts especially collagen fibers provide flexibilty.

What is required to form a cross bridge between a myosin head and an actin filament?

Calcium ions and ATP

Which one of the following statements about aging is most accurate?

Despite some neuronal loss, an unlimited number of neural pathways are available and ready to be developed; therefore, additional learning can occur throughout life.

According to the sliding filament theory, how does muscle contraction occur?

Myosin heads form cross bridges and pull thin filaments, causing them to slide.

What division of the autonomic nervous system is often called the "rest-and-digest" division?

Parasympathetic

Define muscular system.

Responsible for the movement of the body and internal organs

define muscular system

Responsible for the movement of the body and internal organs

What cells form the myelin sheaths around nerve fibers in the PNS?

Schwann cells

What are the two main functional subdivisions of the nervous system?

Sensory and motor

Which term does not describe smooth muscle cells?

Skeletal

Describe similarities and differences in the structure and function of the three types of muscle tissue, and indicate where they are found in the body.

Skeletal-attached to bones, single very cylinder cardiac- located in the wall od the heart, branches with striations smooth- located in the walls of hollow organs (other than the heart),no striations single, fusiform

What must rush into a muscle cell to promote its depolarization?

Sodium ions

Striated involuntary muscle tissue is classified as ________ muscle.

cardiac

The part of the neuron that houses the nucleus is the

cell body

name and describe the describe the various types of fractures

comminuted(bone breaks in 3 or more fragments)compression(bone is crushed)depressed(broken bone is pressed inward)impacted(broken bone ends are impacted into each other) spiral (occurs when excessive twisting force) greenstick(bone breaks incompletely, common in children)

four major skull sutures

coronal, sagittal, squamous, and lamdoid suture

The part of the neuron that receives nerve impulses and acts as an "antenna" is called the

dendrite

Julie experienced a break in the shaft of her femur. What part of her bone was fractured?

diaphysis

major anatomical areas of a long bone

diaphysis and epiphysis

Which of the following neurotransmitters is involved in both Parkinson's disease and ADD?

dopamine

Define and explain the role of the following: endomysium, perimysium, epimysium, tendon, and aponeurosis.

endomysium-wraps the muscle fibers perimysium- wraps a BUNDLE of fibers epimysium-wraps the entire muscle tendon-ends of epimysium that extend muscle (cordlike) aponeurosis- indirectly attaches the muscle to bone

On an exam, you recognize the bone in front of you as a long bone. It has a rather large knobby head and a tuberosity on its proximal end; two epicondyles and two rounded condyles are present on the distal end. What bone marking or characteristic helps you conclude the bone is a femur?

epicondyle

The network of nerves that radiates out from the brain and the spinal cord is part of

the peripheral nervous system.

The shortening of a skeletal muscle fiber during contraction involves ________.

the sarcomeres shortening

Without the protein myosin, a muscle would lack

thick filaments

A muscle is stimulated at a frequency that allows the muscle to relax completely between contractions. However, the amount of tension increases with each contraction. What is this called?

treppe