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Muscle development - ANSWER>>From mesoderm
1) cardiac: involuntary, cannot repair itself
2) skeletal: voluntary
3) smooth: involuntary
Muscle groups - ANSWER>>Ste at week 9
Fibre typing at week 10
Hyperplasia followed by hypertrophy
Gender differences - ANSWER>>Males are larger/heavier compared to females,
but females are skeletally more mature (and at less risk of mortality)
Body growth - ANSWER>>Fat peaks at 9 mo
- function for body temperature
- muscle tissue increases slowly
Patterns of growth - ANSWER>>1) Cephalo-caudal: head to toes
2) Proximo-distal: inner to outwards, proximally located things are most
important
Functions of Nervous System - ANSWER>>- Sensory: receives and transmits info
- Integrative: processes and sends
- Motor: stimulates muscle
Components of NS - ANSWER>>CNS: brain and spinal cord
PNS: sensory and motor nerves
Micro development - ANSWER>>Neurons: send and receive sensory info, many
are made rapidly
,Dendrites: recieve info
Axon: transmits info
Glial cells: support neurons and make up myelin sheath
Process of neuron development - ANSWER>>1) Cell production
- 2nd trimester begins
- 250000/minute
2) Cell migration
- movement of immature cells
- axons grow and connect
3) Cell elaboration
- neurons specialize
- infancy/toddlerhood are very sensitive periods
- tests on kittens
Macro development - ANSWER>>CNS starts as neural tube
- hindbrain: cerebellum: breathing, digestion (most important section)
- midbrain: connections, interpretations
- forebrain: cerebral cortex: higher centers, recieves sensory info
Synaptogenesis - ANSWER>>Creation of the synapse
Synaptic pruning - ANSWER>>Death of unused neurons
4 lobes - ANSWER>>Frontal: movement, intelligence, emotion
Temporal: hearing
Occipital: seeing
Parietal: senses, proprioceptive
Lateralization - ANSWER>>Each lobe controls movement of the opposite side
Left: language and positive emotion
Right: spatial and negative emotion
, Homunculus - ANSWER>>Reflects how the brain controls different components of
the body
- motor: greater for fingers, lips
- somatosensory is for sensory info, but is similar
1) Hearing - ANSWER>>Outer ear: pinna
Middle ear: ear drum, malleus, incus, stapes
Inner ear: cochlea
- hair cells are auditory nerve receptors that interpret sound
Infant hearing - ANSWER>>Infants organize sound, identify locations, recognize
sounds
- at 3 mo, sound threshold becomes reduced
- at 12 mo, we link cognition with sounds
2) Vision - ANSWER>>Cornea, iris, pupil, sclera
Protection: tears, eyelid, eyelashes (2 external, 1 internal)
Basal: normal tears to lubricate eye
Reflex: Produced if foreign object enters eye
Psychic: As a result of emotion
Internal eye structures - ANSWER>>Retina: sensitive lining with cones and rods
Macula densa: highest concentration of cones, central vision
Fovea centralis: spot of greatest concentration on macula densa
Optic nerve head in retina
Vitreous body: fluid-filled hollow area
Infant vision - ANSWER>>First 6 mo: 20/600 to 20/100
By 11 mo, near adult vision
Depth - ANSWER>>Ability to judge the distance between objects and from objects
to oneself
- perhaps somewhat innate, but develops with experience