Allometry

Question 0

Average weights & heights of children at the same chronological age are increasing. This trend towards increasing size is also apparent in adults but to a lesser extent

Answer 0

True

Question 1

What is the principle of similitude?

Answer 1

In similar geometric figures, the surface area increases as the square of the linear dimensions & volume increases as the cube

Question 2

Children are not only getting bigger they are maturing earlier

Answer 2

True

Question 3

What are the reasons for the trend towards earlier maturation?

Answer 3

• improved nutrition allowing for optimal growth
• link between nutritional status, weight, fatness & timing of sexual development (critical weight hypothesis)
• improved environmental circumstances (adequate housing, clean water)
• drop in incidence of childhood disease (antibiotics,vaccination,immunization)
• second-hand hormones (in meat, milk & poultry)
• chemicals in the environment
• increasing overt sexuality in the popular media

Question 4

Correlation does not mean causation

Answer 4

True

Question 5

What is allometry?

Answer 5

Dimensional relationships during growth

Question 6

Archimedes

• laws of mechanical advantage (lever & fulcrum)
• inventor of the water screw (a device to raise water)
• law of buoyancy
• first to approximate pi
• principle of simlitude

Answer 6

True

Question 7

Thermoregulation is dependent on body size

• heat production is dependent on body mass
• heat dissipation is dependent on surface area
• large animals have trouble in the heat because the ratio of surface area/mass is relatively small
• small animals have trouble in the cold because the ratio of surface area/mass is relatively large

Answer 7

True

Question 8

Heat loss
Radiation: the skin emits small amounts of radiant energy
Conduction: heat passes from the skin to a cooler object
Convection: cooler air currents remove heat from the skin
Evaporation: body heat is used to turn sweat into water vapour at the skin

Answer 8

True

Question 9

There are 3 levers in the human body
3rd class most common
Effort-fulcrum-load

Answer 9

1st class is like a see saw, the fulcrum is in between the load and the effort
2nd class is like a wheelbarrow, the load is inbetween the effort & fulcrum
3rd class is like an arm, the effort is inbetween the load & fulcrum

Question 10

Muscle growth
Prenatal - hyperplasia
Postnatal- hypertrophy

Answer 10

True