Module Two Flashcards
what are 5 common forms of movement in humans
locomotion
climbing
throwing
jumping
swimming
what type of symmetry do humans show
bilateral symmetry- allows organisms to move purposefully and efficiently.
what are the features of monkeys that allow for swinging
long arms
flexible rotating wrists
highly mobile joints
more narrow rib cage
upright posture
scapulas that allow for overhead reaching
what caused us to move to bipedalism?
it was favoured by natural selection, through walking on two feet it meant that hominins could travel further in more open habitats
what did becoming taller do to hominins
it lengthened the back muscles at the base of the spine and hips
what evolutionary changes helped to centre the force of gravity in humans?
the thigh bone got an inward slope down to the knee which required gluteal abductors- developed a big strong bum
what are the human adaptions that favour endurance activities like running?
arched feet with a heel bone
large hip, knee and ankle joints
strong hip and knee muscles (gluteus maximus)
multiple sensitive balance organs
tall narrow body
hairless, sweating and other thermoregulatory mechanisms (this is the most important one for thermoregulation in hot environments)
What is the equation for BMI
mass/ height^2
what does BMI correlate with?
with disease prevalence and mortality rates
what is the only direct measurement of body density
cadaver
they show ratios over internal to subcutaneous fat masses
what are the pros and cons of imaging of tissues
pros
- they can measure fat free mass and bone density
-high accuracy (1-2% error)
cons
-expensive
-technical problems ie atheletes size or recent meal
is fat mass or fat free mass denser?
fat free mass is denser
what are some issues with densirometrey?
pro is that is it accurate with 2-3% typical error
doesnt give info on the distributions of the fat mass or fat free mass.
may have residual air volume in the lungs
trapped air in clothing hair or GI tract
what are five assumptions as a measure of skin folds?
- constant compressibility (within people)
- Skin thickness negligible or constant fraction of skinfold
- Fixed adipose tissue patterning
- Constant fat fraction in adipose tissue
- fixed proportion of internal to external (subcutaneous) fat
why is skeletal muscle mass important?
provides physical capabilities
largest glucose sink
produces heat
insulator
major endocrine organ
major determinant of daily energy use
why is fat mass important?
valuble energy source
insulator
why is fat a valuable energy source?
Its twice as energy dense as carbs and protein?
fat cells provide muscle cells with energy during exercise.
what can relative energy deficit disorder cause in the body and what is it due to ?
it is due to insuffient fat, not having enough energy stores
osteoperosis
amenorrhoea (no period)
can affect males too