Exam 2

Question 1

Growth

Answer 1

Normal process of increase in size produced by accretion of tissue

Question 2

Hypertrophy

Answer 2

enlargement of existing cells

Question 3

Hyperplasia

Answer 3

multiplication or production of new cells

done in utero

Question 4

Accretionary growth

Answer 4

increase in extracellular material

Question 5

True growth

Answer 5

An increase in structural tissue (muscle, bone, vital organs), NOT fattening (an increase in adipose tissue)

Question 6

Differentiation

Answer 6

Process by which cells and organs acquire individual characteristics.
Done prenatally

Question 7

Morphogenesis

Answer 7

Organization of dividing cells into specific organs

Question 8

Maturation

Answer 8

Becoming fully developed; highest stage of complexity

Because tissues and body parts grow and develop at different rates, it is hard to determine exactly when this occurs.

Question 9

Senescence

Answer 9

Begins in individual organs and tissues when they undergo degenerative changes without complete repair or replacement

Question 10

Prenatal Growth

Answer 10

Defined as period from conception to birth. (gestation)

Question 11

Ovum Phase

Answer 11

from fertilization to gastrulation (ectoderm, mesoderm, and endoderm development)
lasts up to 14 days

Question 12

Embryonic Phase

Answer 12

tissue, organs and systems are differentiated with increase in size
lasts 25 to 45 days in most mammals

Question 13

Fetal Phase

Answer 13

from embryonic phase to birth.

growth of fetus organs and tissues.

Question 14

Postnatal Growth

Answer 14

Not easily defined
Changes occur in body conformation and composition
Growth curve is the same for all species (sigmoid shaped curve)

Question 15

Differentiation

Answer 15

Depends on changes in protein synthesis.

Question 16

DNA

Answer 16

contains instructions for synthesizing numerous proteins

Question 17

Myogenesis

Answer 17

The molecular, biochemical, and morphological events that occur during the formation of muscle fibers.

• Occurs throughout the lifetime of most domestic meat animals.
• Most occurs during the embryonic and fetal phases of prenatal development

Question 18

Myoblasts

Answer 18

Fuse with one another and donate their nuclei to a single immature muscle fiber known as a myotuble

Question 19

Primary myotubes

Answer 19

First myotubes formed in developing embryos and fetuses. Give rise to primary muscle fibers

Question 20

Secondary myotubes

Answer 20

Form later in fetal development around primary fibers to produce secondary muscle fibers

Question 21

Contractile proteins

Answer 21

Accumulate as the primary and secondary fibers mature

Question 22

Diameter

Answer 22

increases little during the first 2/3 of prenatal period. Increase in weight due to hyperplasia

Question 23

Growth in length

Answer 23

occurs through the addition of sarcomere units to the ends of myofibrils

Question 24

Muscle Fibers

Answer 24

Grow by increases in their diameter and length

Question 25

Diameter increases

Answer 25

increase in the number and size of myofibrils

Question 26

Larger animals

Answer 26

At maturity, do NOT have larger diameter muscle fibers than smaller animals. They have more fibers.

Question 27

Growth in Length

Answer 27

Accomplished postnatally by increases in length of existing sarcomeres and the addition of new sarcomeres

Question 28

During growth

Answer 28

Protein:DNA ratios undergo increases that are less than would be expected for the amount of protein deposited

• indicates nuclei are increasing in numbers
• nuclei present are no longer able to divide
• new nuclei are created from specialized cells called satellite cells

Question 29

Satellite cells

Answer 29

• Provide fibers with added DNA which increases the muscle’s ability to synthesize protein and grow
• Also responsible for the formation of new myofibers during postnatal growth