Lecture 9: Adaptation, Acclimation and Plasticity Flashcards Preview

APS 136 animal physiology, reproduction & development > Lecture 9: Adaptation, Acclimation and Plasticity > Flashcards

Flashcards in Lecture 9: Adaptation, Acclimation and Plasticity Deck (12)
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1
Q

Physiology

A

analysis of the function of living organisms; applies physical and chemical methods to biology

2
Q

comparative:

A

Study of the diversity and modulation of highly conserved properties (physical and biochemical) of organisms

3
Q

Means that comparative physiology contributes to:

A
  • Ecology - deals with the relations of organisms to one another and to their physical surrounding
  • Evolution - correlates function with structure which can help determine relatedness
4
Q

Level of study:

A

organism: -cellular
- molecular
- genetic

  • Compare adaptions of similar organisms in different environments
  • Compare different organisms in similar environments
5
Q

Adaption:

A

Trait that improves an organisms performance (Fitness) in it environment.
–i.e. it is selected; organism that has this trait survives better and leaves more offspring to next generation
• Makes the organism more fit for current environment
-are heritable
-time scale
—evolutionary = long term

6
Q

Acclimatisation :

A

natural

7
Q

Acclimation :

A

experimental

8
Q

Acclimatisation & acclamation:

A
  • Physiological compensatory response (short- term) to environmental change
  • E.g., in the short-term, under low [O2] [concentration], the body makes more red blood cells to acquire more O2 in the body.
  • E.g., in the short-term, under heat stress, vasodilation occurs to dissipate excess heat.
  • Time scale – minutes to hours to days to weeks to months
9
Q

example to living in extreme environments: Himalaya & Andes

A
  • high altitude living extreme
  • highlanders
  • problem as low atmospheric [O2] = hypoxia
  • at 4000m, only 60% of [O2] than at sea level
  • Tibetans have lived at 4000m >25K yrs
  • Andean at 4000, for about half that time

RESULTS:
Amount of O2 saturation (4000 m)
• Andeans 2.6% greater than Tibetans
• Andeans are marginally “less stressed” at ~4000m than Tibetans in terms of O2 saturation but are more stressed with downstream consequences of this higher [Hb]

10
Q

how can you increase RBCs and therefore (Hb) Haemoglobin

A

through erythropoiesis by making EPO (erythropoietin)

11
Q

Tibetans vs Andeans altitude of response

A

also differs
–Tibetans not respond with increased Hb until ~4000m whereas Andeans respond at 1600m
• Tibetans require a much stronger stimulus and have smaller response

12
Q

Tibetan adaptions to high altitude

A
  • Dominant autosomal gene for oxygen saturation
  • Confers 5-6% higher oxygen saturation
  • Genealogical, O2 saturation and female fertility data collected for 681 women
  • Homozygous recessive mothers had lower number of surviving children due to increased infant mortality
  • High altitude hypoxia acts as an agent of natural selection