Unit B

Question 1

What are the 3 Prenatal Stages?
How long is each stage?
What happens in each stage?

Answer 1

Prenatal stage is 40 weeks
1. Egg
first two weeks
cell division and differentiation
a lot of hyperplasia
2. Embryo
weeks 2-8
increase in cell number and cell differentiation
almost all organs are formed
3. Fetus
weeks 9-40
increase in cell size and mass
functional development

Question 2

Fetal Growth (2 points)

Answer 2

fetus increases in length at constant weight

weight gain happens near the end of the pregnancy

Question 3

Fetal Development (3 points)

Answer 3

heart tissue: 4 weeks
trunk, arms, and legs: 6-9 weeks
reflexes: 36 weeks

Question 4

Factors Affecting Prenatal Growth and Development (5 things)

Answer 4

nutrition
alcohol: affects growth and CNS (irreversible)
smoking: affects growth and brain
caffeine
recreational drugs

Question 5

What are the 3 types of bone cells and what do they do?

Answer 5

osteoblasts: bone formation
osteoclasts: bone resorption
osteocytes: regulation of flow of minerals and nutrients

Question 6

Bone Growth and Remodelling

Infancy vs Adulthood

Answer 6

infancy: 50% annually
adulthood: 5% annually

Question 7

Formation vs Resorption Rates Throughout the Life (3 points)

Answer 7

youth: formation > resorption
adult: format = resorption
old: formation < resorption
- leads to osteoporosis

Question 8

How can you Prevent Osteoperosis? ( 3 points)

Answer 8

exercise to increase peak bone mass
nutrition
pharmaceuticals

Question 9

What are the 3 Types of Bone Growth?

Answer 9

growth: longer, wider
modeling: change in shape
remodelling: change in shape again

Question 10

What effects Growth? (7 points)

Positive or Negative Growth?

Answer 10

thyroid hormone (positive)
GH (positive)
IGF-1 (positive)
estrogen (positive)
androgens (positive)
cytokines (negative)
corticosteroids (negative)

Question 11

Bone Mass Throughout the Life ( 3 points)

Answer 11

Birth: 3% of body mass
adult male: 6-7% body mass
adult female: 6-7% body mass

Question 12

Calcium Content in Bone Throughout Life (3 points)

Answer 12

Birth: 25g
Adulthood: 1000g
Old age: 600G

Question 13

What are the 3 Types of Muscle Tissue?

Answer 13

Skeletal
Smooth
Cardiac

Question 14

What is Myogenesis? (1 point)

Answer 14

increase in the number of fibres

Question 15

What does Myostatin do? (1 point)

Answer 15

Slows down muscle growth

Question 16

What are the 3 types of Connective Tissue? Where are they?
Why is Connective Tissue Important? (1 point)
What Happens to the Tendon with Growth? (2 points)

Answer 16

endomyosin is around the fibre
perimysium is around a bundle of fibres
epimysium is around the whole muscle
important in transmitting force to bone
increased tendon stiffness with growth
decreased tendon compliance with growth

Question 17

What Happens to Muscle Fibre Size with Growth and Aging? (2 points)

Answer 17

increase in diameter with growth (until middle age)

decrease in diameter with aging (after middle age)

Question 18

What Happens to Muscle Mass with Age? What causes this?

Answer 18

increase muscle mass
due to hypertrophy of muscle which is caused by increase in fibre size and increase in number of nuclei per fibre
(number of fibres doesn’t really change)

Question 19

What are Adipocytes? (1 point)

Answer 19

the cells that make up fat tissue

Question 20

What are the functions of fat tissue? (4 points)

Answer 20

energy storage
insulation
mechanical protection
regulation of biological function

Question 21

What does Leptin regulate? (7 points)

Answer 21

energy balance
appetite, food intake
glucose and lipid metabolism
puberty
reproductive function
angiogenesis
bone formation

Question 22

What molecules are secreted by adipocytes? (4 points)

Answer 22

leptin
IGF-1
estrogen
angiotensin

Question 23

How do adipocytes regulate biological functions? (6 points)

Answer 23

energy balance
glucose and insulin metabolism 
lipid metabolism 
immunity
reproduction, puberty
blood pressure

Question 24

What is Adipogenesis? (1 point)

What is the process? (4 points)

Answer 24

adipogenesis is fat formation

adipoblasts
pre-adipocytes
very small adipocytes
mature adipocytes

Question 25

Fat cell size during growth (2 points)

Answer 25

hypertrophy in first year of life

variable hypertrophy during puberty

Question 26

Fat cell number during growth (2 points)

Answer 26

no change during infancy

hyperplasia during childhood and adolescence

Question 27

What is body composition? (2 points)

Answer 27

typically means the percentage of fat in the body

partitioning and quantifying basic components of body mass

Question 28

what is the importance of body composition? (3 points)

Answer 28

sport performance
thermoregulation
risk factor of diseases

Question 29

How do you measure BMI? (1 point)

What do the numbers indicate? (4 points)

Answer 29

BMI = mass / (height)^2

<20: underweight
20-25: healthy
25-30: overweight
>30: obese

Question 30

What are 3 reasons for increases in obesity?

Answer 30

increased caloric consumption
increased fat consumption
decreased physical activity

Question 31

relationship between physical activity and age (1 point)

Answer 31

physical activity decreases with age

Question 32

reasons for decreases in physical activity (4 points)

Answer 32

increased urbanization
decreased safety considerations
decreased facilities
increased technologies

Question 33

Risks with childhood obesity (7 points)

Answer 33

increased risk of high BP
increased risk of heart disease
increased risk of high cholesterol
increased risk of diabetes
respiratory problems
orthopaedic problems
psychological problems

Question 34

what came first? overweight or low physical activity?

Answer 34

lower PA before becoming overweight