Module 2 Muscle Growth And Development Flashcards Preview

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Flashcards in Module 2 Muscle Growth And Development Deck (72):
1

What is the normal process of increase in size produced by accretion of tissues similar in constitution to those of the original tissue or organ

Growth

2

How do animals grow?

Increase in height, length, girth, and weight. Size and weight of structural tissues increases

3

What is hypertrophy

Enlargement of existing cells

4

What is hyperplasia

Multiplication or production of new cells through mitosis or prenatally. No Change in cell size

5

What is accretionary growth

Increase in extra cellular material

6

What is true growth vs fattening

True growth is an increase in muscle tissue

7

What is net growth

Tissue synthesis minus tissue degradation

8

Growth is liner true or false

False

9

Why is growth not linear

Proteins turn over every 21 days

10

What is development

Gradually progressing from a lower complexity to a higher complexity

11

What is differentiation

Process by which cells and organs acquire completely individual characteristics.. progressive diversification of cells of embryo into muscle cells, brain cells, liver cells, etc

12

What is morphogenesis

Organization of various dividing cells into specific organs

13

What is maturation

Process of becoming fully developed and reaching the highest stage of complexity

14

What is senescence

When individual tissues and organ are no longer maintained in their mature form and undergo degenerative changes

15

What are the 3 phases of prenatal growth

Ovum, embryonic, prenatal/fetal

16

What is the ovum stage

Fertilization to gastrulation (when primary cell layers develop: ectoderm, mesoderm, and endoderm)

17

What is the embryonic stage

Differentiation of organs, tissues, and systems

18

When is the most prenatal growth

Last 1/3

19

What determines the length of gestation

Animal complexity

20

What is myogenesis

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

21

When does myogenesis occur

Prenatally

22

What type of cells does myogenesis form

Multinucleated muscle cells

23

What are myoblasts

Muscle precursor cells that fuse to form fibers

24

What is proliferated mitosis

Creation of daughter cells identical to parent cells

25

What are the steps of myogenesis

Multipotent stem cells undergo proliferation and differentiation, becoming myoblasts. Myoblasts line up and fuse forming a myotube, which forms muscle fibers

26

What type of cell growth occurs prenatal

Hyperplasia and hypertrophy

27

What kind of growth occurs postnallay

Only hypertrophy (no new cells after birth)

28

How do muscle fibers grow postnatally

Increase in length, adding sarcomeres to each myofibril

29

How to muscle cells grow postnatally

Increase in diameter, adding new myofibrils in each cell

30

What happens to the rate of myofibril growth over time?

Growth levels off

31

Fiber number is _____ at birth

Fixed

32

Hypertrophy results in increased:

Muscle cell size and weight

33

dna/protein ratio must remain constant in the cell during hypertrophy true or false

True

34

Why is more DNA needed for protein accumulation and cell growth?

The ratio must be constant

35

What must there be more of in order to provide extra DNA for hypertrophy cells

Nuclei

36

How is nuclei obtained for extra DNA for hypertrophy

Satellite cells

37

What are satellite cells

Non-fused myoblasts present in muscle cells after birth

38

What happens to satellite cells as animals age?

Decrease

39

What happens to growth when satellite cells decrease

Muscle growth is slower

40

What two things can increase muscle diameter

Fat cells and connective tissue

41

Where does termination of a muscle fiber occur?

Throughout the muscle, not just at the end

42

All muscle fibers are ______ at birth meaning they are:

Type 1: Red, with the most oxidation requirements

43

What happens to muscle fibers after birth?

Differentiation into White and intermediate types

44

Why do fibers differentiate into other types after birth?

Nerve influence and sequence of morphological changes experienced by developing fibers (exercise)

45

What is a fibroblast

Precursor cell to connective tissue, developing into tropocollagen, tropoelastin, and ground substance

46

Amount of connective tissue is related to:

Muscle function

47

Quality of collagen changes with:

Age (decreases with age)

48

Where would you find the most connective tissue: back or limbs?

Limbs

49

What gradually develops into lobes and lobules that are enclosed in collage our fibers and supplied with blood capillaries

Adipose tissue

50

What is an adipoblast

Starts to accumulate lipids

51

What is an adipocyte

Filled with lipid

52

Which is larger, adipoblast or adipocyte

Adipocyte

53

What is another term for visceral fats

Internal fats

54

What is KPH fat?

Visceral fats (Perirenal fat, pericardial fat, Mesenteric)

55

What is perirenal fat

Kidney fat

56

What is pericardial fat

Heart fat

57

What is mesenteric fat

Intestinal fat

58

What is subcutaneous fat

Just under the skin, fat used for yield grading, undesirable for cutability

59

What is Intermuscular fat

Fat between muscles, seam fat, undesirable for cutability

60

What is intramuscular fat

Fat within muscle, marbling, desirable for palatable to and quality grades

61

What is intracellular fat

Membrane phospholipids, most responsible for beef flavor development

62

What fat is the first deposited?

Internal fat

63

What is the first fat utilized

Intramuscular

64

Why do beef need fed for a long period

Marbling is deposited last

65

Growth of adipose tissue is highly _________ and depends on:

Variable: Genetics, calories fed

66

As fat percentage increases, what happens to moisture and protein?

Both decrease

67

What is the leanest gender for cattle

Bulls

68

What is the fattest gender for cattle

Heifers

69

What is the leanest gender for sheep?

Ram

70

What is the fattest gender for sheep?

Ewes

71

What is the leanest gender for hogs?

Boars

72

What is the fattest gender for hogs?

Barrows