Week 13: Noise/Exposome

Question 1

Noise

Answer 1

Unwanted sound

Sound is created when objects vibrate - air is compressed and expanded forming waves

Question 2

Sound waves

Answer 2

Amplitude and frequency

Question 3

Path of hearing (4)

Answer 3

1) Sound waves enter, travel to ear drum
2) Eardrum vibrates with incoming sound, sending vibrations to middle ear bones
3) Vibrations from middle ear travel to inner ear, cochlea, which activate tiny hair cells which release neurochemical messengers
4) Auditory nerves cary electrical signal to brain

Question 4

Factors affecting noise propagation

Answer 4

Source, distance, atmospheric absorption, wind, temperature and gradient, obstacles, ground absorption, reflections, humidity, precipitation

Question 5

Decibel

Answer 5

Logarithmic unit of measurement that expresses the magnitude of the sound pressure level
Loudest: 195dB

Question 6

Disturbances from noise

Answer 6

Sleep
Attention span
Cognitive

Question 7

Psychological effects of noise

Answer 7

Lack of control, anxiety, aggression, depression

Question 8

Epidemiological evidence of noise exposure

Answer 8

Stress - increased BP and HR leading to cardiovascular disease
Diabetes
Immune depression
Problems with fetal development

Question 9

Exposome

Answer 9

Combined exposures from all sources that reach the internal chemical environment

Question 10

Epigenetics

Answer 10

Study of inherited changes in phenotype or gene expression caused by mechanisms other than changes in underlying DNA sequence
DNA methylation

Question 11

DNA methylation

Answer 11

Methyl markers added to certain DNA bases that repress gene activity

Question 12

Histone modification

Answer 12

When histones are tagged or acetylated, chromatin is open and genes are active
When histones are not chemically tagged, deacetylated, the chromatic condenses and genes silenced

Question 13

Non-coding RNAs

Answer 13

RNA not used to make proteins, but can be cleaved and used to inhibit protein-coding RNAs