KNES 355 Quiz 2 questions with correct answers
Distance Growth Curve Correct Answer-Height (cm) or weight (kg) at
each age (years), curve shape (sigmoid) similar for both sexes and for
weight and height (but although general shape is sim, there are
differences, e.g. weight increases slows down more than height increase)
Half adult stature achieved at age Correct Answer-2
Stature growth curve male vs female Correct Answer-males final stature
typically taller, Males slightly taller than females at all stages except 11
to 13 years (female PHV)
Body mass growth curve Correct Answer-Lag in growth in body weight
is seen during pre-natal stage of development (stretch then fill/grow long
before grow strong), 20% of full adult weight at age 2
Distance growth curve - growth segments Correct Answer-infancy (first
more rapid growth period), childhood (less rapid but slow continuous
growth), and adolescence (puberty causing the onset of another rapid
growth spurt, this is when males and females start to differ in stature and
weight)
Velocity Curve take off Correct Answer-onset of puberty, when growth
starts to accelerate
Velocity Curve peak height velocity Correct Answer-highest growth rate
obtained during puberty (e.g. 13cm/year is the largest rate of growth)
,Velocity Growth Curve Correct Answer-Mostly deceleration from birth
until mid-childhood growth spurt, Boys have prolonged (+2 yrs)
appendicular growth at a rate of 5.5 cm/yr (this is the primary cause of
final stature differences, 10+ cm diff from females), Larger amplitude of
spurt in boys - 9.5 cm/yr boys vs 8 cm/yr girls, larger rate of growth for
boys
Mid-Childhood Growth Spurt Correct Answer-NOT EVERYONE
GETS A MID-CHILDHOOD GROWTH SPURT - More common in
boys 80% vs. girls 33%, Occurs between 6 to 8 yrs, Magnitude of
velocity increases by at least 1cm/year, Occurs earlier in girls by 1yr,
Compare to velocities during pubertal growth spurt of 8 cm/yr (girls)
and 9.5cm/yr (boys)
velocity curve slope Correct Answer-shows acceleration
(increasing)/deceleration (decreasing), steeper = greater rate of change,
shallower = slower rate of change
Velocity curves male vs female Correct Answer-girls take off earlier by
about 2 years (mature earlier than boys), boys have a greater PHV
(greater rate of growth), boys continue growing for about 2 years longer,
However, individual variation is considerable
Age Increment Correct Answer-difference of ages, Age 2 - Age 1, e.g.
10 vs 9, age increment = 10 - 9 = 1 year
,Height Increment Correct Answer-difference of height, Height 2 -
Height 1, e.g. 180cm vs 170cm, height increment = 180 - 170 = 10cm
Whole Year Velocity Correct Answer-growth velocity in terms of 1
year, Height Increment / Age Increment, e.g. age increment = 1.5yrs,
height increment = 8cm, 8cm/1.5yrs = 5.33 cm/yr
Age Centre Correct Answer-Average age, (Age2 + Age1)/2, e.g. 10 vs 9,
(10 + 9) / 2 = 9.5yrs, use age center when comparing to velocity curve
Velocity Growth Curve: Body Mass Correct Answer-Early acceleration
(days/weeks), then deceleration, then acceleration again at age 2-3,
Pubertal growth spurt is a period of sex dichotomy in body composition
- males get more lean mass during puberty, females get more fat mass
during puberty, Age at peak weight velocity (PWV) usually later than
PHV by 6 months (again stretch then fill/long then strong)
Velocity Growth Curve: Male body composition Correct Answer-
Skeletal tissue & muscle mass (~ 7.2 kg/yr), Fat mass - more stable/rate
stays constant (0.7 kg/yr)
Velocity Growth Curve: female body composition Correct Answer-
Skeletal tissue and muscle mass (3.5 kg/yr), Fat mass (continuous
increases of rate; 1.5 kg/yr)
Primary Factors that Account for Changes in Stature and Body Mass
Correct Answer-Endocrine, age, sex, timing, genetics, maturity
, Age and Sex Differences Correct Answer-Largely due to genetics, grow
as you age, final height and mass differences - 13 cm difference in
stature, 12 kg difference in weight
Genetic Influence on Adult Stature Correct Answer-Age of PHV seems
to have a strong genetic factor (timing of maturation), amplitude of PHV
has a moderately strong genetic factor (seems to have a higher
correlation in males than females, May relate to genetic influence on
male pattern of hormone secretion - increase testo and growth hormone
release)
Genetic Influence on Adult Body Mass Correct Answer-Moderately
strong influence on timing of body mass growth spurt (timing of
maturation), Weaker influence on amplitude of body mass growth spurt,
particularly in females (BW has a greater environmental/nurture
influence)
Maturity Influence on Stature Correct Answer-Although there are
moderate to strong genetic influences on timing and amplitude of
maturity, Maturation itself does NOT affect the final growth outcome,
just the tempo of growth
Timing Factors Influencing Growth Correct Answer-diurnal effect,
Seasonal effects, Secular trends