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AVS 109 > Animal Growth > Flashcards

Flashcards in Animal Growth Deck (58):
1

Why study animal growth?

Disease prevention/therapy
Tissue regeneration
Prevent wasting conditions
Optimize health and well-being
Optimize performance
Growth rate and efficiency important in ag.

2

Growth

increase in size or mass of structural tissues or organs- does not include excess adipose tissue (fat) deposition

3

Hyperplasia

increase in cell number

4

Hypertrophy

increase in cell size due to accretion of cell products

5

Differentiation

the process of acquiring characteristics distinct from a progenitor cell or tissue, such as occurs in progressive diversification of cells and tissues of the embryo

6

What types of animals have growth plates that don't stop growing?

Castrated animals

7

What happens during the ovum stage?

Fertilized by sperm
Hyperplasia occurs
As cells differentiate morphogenisis occurs
(cells are not increasing in size at this stage therefore it is not hypertrophic growth.

8

What happens during the Embryonic stage?

High rate of cell division, hyperplasia and simultaneous differentiation
While there begins to be some hypertrophy it is still a minor proportion of the growth

9

What is totipotent?

Totipotent stem cells are one of the most important stem cells types because they have the potential to develop into any cell found in the human body.

10

What is pluripotent?

Can't become everything, but can become a number.

11

Endoderm refers to

internal organs

12

Mesoderm refers to

skeletal muscle

13

Ectoderm refers to

brain, nerves, skin, and hair

14

What are the three germ layers?

Endoderm, Mesoderm, and Ectoderm

15

What occurs during the Fetal stage?

Both hyperplasia and hypertrophy
Dramatic increases in both cell number and size
Represents 80-85% of prenatal time period

16

What occurs during the post-natal stage?

Most muscle growth (nearly all) is hypertrophic growth
Some tissues such as adipose show propensity for both hyperplasia and hypertrophy.

17

What does neonatal mean?

newborn

18

How many more muscle fibers grow after you're born?

None

19

There is a change in what as we develop?

Proportion

20

Allometry

relationship of growth of a part of an organism to growth of the whole organism

21

During allometry, what happens?

growth at different rates

22

Apoptosis

programmed cell death

23

Atrophy

decrease in size of a cell, tissue, organ, or part

24

Development

change in form and/or function of the animal or tissue, which results from changes in the rate of increase or decrease of individual components of the body or tissue.

25

When does Atrophy happen?

If you don't actively use the muscles.

26

What is the opposite of Atrophy?

Hypertrophy

27

An increase in strenuous exercise would happen during what?

Hypertrophy

28

What is Hypertrophy and Atrophy influenced by?

Gender

29

What increases the speed of the growth plates in females?

Estrogen

30

What recieves its share of nutrients first when referring to the runt of the litter?

Brain and central nervous system

31

T or F? Everything in the body grows at the same time, but at different rates.

True

32

The white in bones is what?

Cartilage

33

What is in the Epiphyseal Growth Plate?

Epiphyseal Cartilage

34

When there is a lack of use within bones, what happens? (females)

break down of the bone

35

Hyperplasia exists in what stage of skeletal muscle development?

Cell division

36

What is the name for the cells during cell division?

Myoblasts

37

What is a myotube?

Immature muscle fiber

38

What is myogenesis?

muscle fibers form

39

What is adiopogenisis?

formation of adipose tissue

40

What is myostatin?

Muscle inhibitor (growth factor) that inhibits muscle development

41

What does naturally occuring myostatin mutations cause in animals?

Double muscling

42

What happens with double muscling?

Myostatin mutations
More muscle fibers
Larger muscle fibers
Higher percentage white muscle fibers
Less body fat
High incidence of dystocia
Very little intramuscular fat
Tender meat

43

What is dystocia?

calving difficulty

44

DNA accretion in post natal growth

nuclei incorporated into pre-existing muscle fibers by satellite cells
increase muscle fiber's capacity for gene expression and growth

45

Protein accumulation in post natal growth

accounts for majority of muscle fiber hypertrophy
accumulation of myofibrillar protein occurs when protein synthesis exceeds protein degradataion

46

What is a satellite cell?

adult myoblast

47

What is an adipocyte?

a unilocular lipid

48

Lipids account for what percentage of tissue?

76-94%

49

Triacglycerols (triglycerides) account for what percentage of lipids?

90-99%

50

The diameter of an adipocyte is normally?

15-200 um

51

Are adipocyte cells organized in clusters?

Yes

52

What happens during the phases of fattening?

Hyperplasia is followed by hypertrophy
recruitment of new fat cells (hyperplasia) can occur

53

What is increased during fattening?

Adipose tissue and number of fat cells

54

Why is fat in the body accumulated?

It is accumulated because of hyperplasia, and because of the increasing size (hypertrophy).

55

Is growth hormone an FDA approved growth regulator?

No

56

What is differentiation?

acquiring different specialized characteristics

57

Embryonic growth accounts for what percentage of the prenatal period?

15-20%

58

What can happen with stem cells?

Zygote can become anything
cells become more highly differentiated