Exam 1

What are the four types of muscle fibers?

Type I
Type IIA
Type IIX
Type IIB

What are the two kinds of red muscle fibers?

Type I
Type IIA

What is considered the intermediate muscle fiber?

Type IIA

What are the two kinds of white muscle fibers?

Type IIX
Type IIB

Which kind of muscle fiber contains more myoglobin, red or white?

Red

Which kind of muscle fiber is larger in diameter, red or white?

White

Which kind of muscle fiber contracts faster, red or white?

White

Which kind of muscle fiber contains more mitochondria that are also larger, red or white?

Red

Which kind of muscle fiber has a higher capillary density, red or white?

Red

Which kind of muscle fiber is ran by oxidative metabolism, red or white?

Red

Which kind of muscle fiber is ran by glycolytic metabolism, red or white?

White

Which kind of muscle fiber has a higher lipid content, red or white?

Red

Which kind of muscle fiber has a higher glycogen content, red or white?

White

Which type of muscle fiber has a larger Z disk width, red or white?

Red

Is a wider Z disk width or thinner one more tender?

wider

What pigment makes meat red?

myoglobin

What are the three types of muscles?

Smooth
Striated - Involuntary
Striated - Voluntary

what is a muscle?

a band or bundle of fibrous tissue in a human or animal body that has the ability to contract, producing movement in or maintaining the position of parts of the body.

Nebulin

actin-binding cytoskeletal protein that is localized to the I-band of the sarcomeres in skeletal muscle

Among the chemical components of meat, \_____ is the most abundant?

moisture

As an animal grows older, connective tissue:

Matures and becomes stronger
Decreases meat tenderness
Generates more intermolecular cross links
Is influenced by hormones

Cytoskeletal protein that connects the Z line to the M line in the sarcomere

Titin

Calcium in the muscle is stored in the:

sarcoplasmic reticulum

Connective tissue that connects bone to bone

Ligament

Directional term meaning toward the median plane

Medial

In mammalian skeletal muscle, the nuclei are located

at the periphery of the fiber, beneath the sarcolemma

Intermuscular fat is deposited in the

Epimysium

Intramuscular fat is deposited in the

Perimysium

Mitchondria are:

'Powerhouse' of the muscle cell

Myofibrils:

are unique to muscle fibers
run parallel to the long axis of the muscle fiber
are comprised of myofilaments

On a compositional basis, \______ is the most variable component of meat

Lipid

Marbling is deposited in the \______

Perimysium

The most abundant fatty acid in the animal body

Oleic

The amino acid, \_______, is unique to collagen

Hydroxyproline

The laboratory exercises comprise \_____% of your final grade in this course.

30

The portion of the myofibril spanning two adjacent Z disk is called:

Sarcomere

The thick filament is also known as the \______ filament.

Myosin

Which of the following would be associated with Type 1 MHC muscle fiber types?

Oxidative metabolism
Red in color
Small diameter
Slow contraction speed
High lipid content
More mitochondria

A total of six thick filaments surround one thin filament in the sarcomere (T or F)

False

Actin filaments cross the z-disk (T or F)

False

Collagen in meat is classed as salt soluble (T or F)

False

Collagen is the most abundant protein in the animal body (T or F)

True

Connective tissues in meat are fibrous in nature (T or F)

True

Fatty acid chains of 10 or fewer carbon atoms are common in animal fat (T or F)

False

Meat is an excellent source of protein in the diet (T or F)

True

Neutral lipids are mostly found in meat in the form of phosphoglycerides (T or F)

False

Oxygen is required for oxidative metabolism in the mitochondria ( T or F)

True

Skeletal muscle fibers contain multiple nuclei (T or F)

True

Skeletal muscle gets its striated appearance because of myofilament arrangements (T or F)

True

The infraspinatus and serratus ventralis muscles can be found in cuts from the round/leg (T or F)

False

The lipids found in cell membranes are classified as triglycerides (T or F)

False

The most abundant inorganic constituent in the animal body is potassium (T or F)

False

The percentage of carcass to live weight increases as live weight increases (T or F)

True

The predominate protein comprising the thin filament is actin (T or F)

True

The predominate type of lipids found in carcass tissues are polar lipids (T or F)

False

The relative proportions of muscle, bone and fat tissues in carcasses of constant weight determines carcass value (T or F)

True

The sarcolemma is the membrane surrounding the muscle fiber (T or F)

True

The sarcotubular system of the sarcoplasmic reticulum is associated with each sarcomere (T or F)

True

The true cell of a skeletal muscle is the myofibril (T or F)

False

There are only thick filaments in the I band (T or F)

False

You are responsible for all the material missed in this course due to an excused absence (T or F)

True

You have two week to complete any assignments missed due to an excused absence (T or F)

False

List the chemical composition components of skeletal muscle and the average abundance (% weight) of each

Moisture 75%
Protein 18.5%
Non Protein Nitrogen 1.5%
Carbohydrates 1%
Inorganic 1%
Lipids 3%

List the four fat deposits by their common names

Marbling (Intramuscular)
Seam (Intermuscular)
External (Subcutaneous)
Internal (Perinephric)

List the three types of protein found in skeletal muscle

Sarcoplasmic
Myofibrillar
Stromal

List the three classes of myofibrillar proteins and an example of each

Cytoskeletal - Titin
Regulatory - Troponin
Contractile - Actin

The characteristics of skeletal muscle tissue are dictated by?

Function

What is the membrane surrounding the muscle fiber called?

sarcolemma

What is the sarcolemma composed of?

proteins and lipids

structures present at the myoneural junction form a raised mound called

the motor end plate

cytoplasm of the muscle fiber

sarcoplasm

There are only \_________ filaments in the H zone

myosin (thick)

There are only \______ filaments in I band

actin (thin)

Four z filaments attach to \____ actin filament

one

What proteins account for 90% of the myofibrillar protein?

Myosin
Actin
Titin
Tropomyosin
Troponin
Nebulin

What are the two types of actin?

Globular actin (G actin)
Fibrous (F actin)

What are the connective tissue proteins?

Collagen
Elastin

What is the most abundant amino acid in collagen?

Glycine

Collagen is more soluble in \______ animals.

young

List the inorganic constituents and their abundance in the body

Calcium - 1.5%
Phosphorus - 1%
Potassium - 0.35%
Sulfur - 0.25%
Sodium - 0.15%
Chlorine - 0.15%
Magnesium - 0.05%

What length of fatty acid chain is most common in the body?

C16-C18

Triglycerides with \_____ palmitic fatty acid and \____ fatty acids are most common in the animal body

One

Two

What is the most abundant carbohydrate in the body?

Glycogen

Which type of protein requires low ionic strength?

sarcoplasmic- water soluble

Which type of protein requires high ionic strength?

myofibrillar - salt soluble

Which type of protein is considered insoluble?

stromal - connective tissue

Percentage of non-carcass components (hide, blood, stomach, intestines and liver) decline with increased live weight (T or F)

True

Motor nerve fibers terminate on the sarcolemma at the?

myoneural junction

The sarcomere is:

basic contractile unit of the muscle

Mitochondria are:

'powerhouse of the muscle cell'

The contractile unit of the myofibril spanning two adjacent Z disk is called:

Sarcomere

Among the chemical components of meat, \_____ is the most variable.

lipid

Type IIX muscle fibers have what characteristics?

white
large diameter
glycolytic metabolism
fast contraction speed
high glycogen content

Type I or IIA muscle fibers have what characteristics?

red in color
small diameter
oxidative metabolism
slow contraction speed
high lipid content

Attending on a portion of lecture or lab will be considered an absence (T or F)

True

Collagen in meat is classed as insoluble in high ionic strength solutions (T or F)

True

Handwritten copies of the lab exercise will not be graded and a score of "0" will be assigned if a handwritten copy is submitted for grading (T or F)

True

If a laboratory exercise is not turned in at the beginning of class, a late penalty of 30% will be deducted from the grade. (T or F)

True

If an exercise is submitted for a lab missed with an unexcused absence, a score of "0" will given for the exercise. (T or F)

True