L12: Physiological Development in Youth Flashcards
What is the difference between chronological and biological age?
Chronological age: Age measured in years since birth
Biological age: Age of cells measured using various biomarkers
In what part of life is metabolism highest?
At birth before steadily declining
In what part of life does metabolism rise slightly before declining again?
During puberty (10 - 16)
Why are there 2 growth spurts in most organs?
One during childhood, another during puberty
Why does the growth rate of the brain plateau earlier than other organs?
In the first two years of life, the brain is already 50% grown
Why do reproductive organs only have 1 growth spurt?
It is of no use during childhood, so it will only develop during puberty
Why does the lymphoid grow twice as large as an adult’s before shrinking to a regular size?
During childhood, the lymphoid is larger as it is exposed to more pathogens and quickly building the immune system
When do males and females tend to reach their full height, and when is their peak rate of height/weight growth?
Full height:
Males: 18
Female: 16
Peak rate:
Males: 14
Females: 12
Besides genetics, what 3 other factors influence the growth of the muscoskeletal system?
- Physical activity
- Nutrition (protein and calcium)
- Sunlight (Vitamin D)
How does Vitmain D interact with calcium in the body?
Vitmain D helps the body better absorb calcium
When does fat-free mass (lean body tissue) plateau for males and females?
Males: 20
Females: 15
What is the average fat percentage for 20 year old males and females?
Males: 15%
Females: 25%
What are growth plates in bones?
Growth plates are composed of cartilage which elongate throughout childhood and adolescence. The body eventually replaces this with bone
In what 3 ways do bones in children differ from bones in adults?
- Smaller, more cartilage
- Less rigidity (tendency for incomplete fractures)
- More haversian canals for blood vessels
By what proportion do the number of alveoli increase from birth to adulthod?
10 fold increase (50 million - 500 million)
For what 3 reasons do children tend to have a higher breathing than adults?
- Smaller lungs
- Smaller tidal volume
- Higher breathing frequency
For what 4 reasons do children tend to have a higher heart rate than adults?
- Smaller heart
- Weaker contractile force
- Less stroke volume
- Higher heart rate
When does growth rate of the nervous system begin to plateau and decline?
Plateau: 20
Decline: After 60 and 80
What is the difference between the amygdala and the cortex?
Amygdala: Responsible for emotions, impulses, and instinctive behaviour
Cortex: Responsible for speech, decision making, and motor skills
When does the pre-frontal cortex finish developing?
After puberty at 25
Besides the gondal hormones, what 3 other homrones change significantly during puberty?
- Dopamine
- Seratonin
- Melatonin
How do the physical activity guidelines differ between adolescents and adults?
Adolescents need to be more active, preferably everyday
