bio final part D

Question 1

effect on loop of henle’s length in conserving water in a desert animal

Answer 1

-Desert animals live in an environment with limited water resources
-so they need to conserve water as much as possible to survive.

1. greater concentration gradient
   - more water reabsorbed from renal filtrate as it pass through nephron
   -production of highly concentrated urine
2. enhance water conservation
   - excrete metabolic waste with minimum water lost
   - maintain body water balance with limited water supply
   - maximum water reabsorption in kidney
   - efficiently extract water from food
   -longer loop means more time and a larger area for reabsorption

Question 2

thermoregulation in people living in arctic area

Answer 2

-arctic area has a cold climate

1. increase metabolic rate
   - generate more heat
2. vasoconstriction
   - reduce blood flow to skin
   - minimize heat lost
3. shivering
   - generate heat through muscle contraction

Question 3

domain bacteria vs archaea

Answer 3

1. both are prokaryotic (don’t have nuclear envelop)
2. both have circular chromosome
3. both are not membrane-enclosed organelle
4. both are unicellular
5. bacteria has peptidoglycan in cell wall while archaea don’t have
6. bacteria have 1 kind of RNA polymerase while archaea have several kind of RNA polymerase
7. bacteria has no histone associated with DNA while some species of archaea have
8. bacteria can’t growth at temperature more than 100degree celcius while some species of archaea can

Question 4

assisted reproduction in solving inbreeding problem in animal

Answer 4

1. IVF (in vitro fertilizations)
   - oocyte collected
   - oocyte kept in culture medium
   - mixed with semen
   - resulting zygote divide to form embryo
   - cultured for several day
   places into mother/female of same/different species
2. artificial insemination
   - collect semen from male animal
   - deposit into the reproductive tract of a female animal using specialized instrument.
   - allow breeding without natural mating
3. embryo transfer
   - collect embryo from a female animal and transfer into reproductive tract of one/more recipient female animal
4. sperm and ovum cryopreservation
   - freeze and store sperm and unfertilized oocyte
   - gene bank for endangered species

Question 5

threats of increased human population

Answer 5

1. climate change
   - greenhouse gas emission increase due to burning or fossil fuel and deforestation
   - alter temperature and disrupt habitat
   - shifts in biodiversity and increase extinction risk
2. habitat lost
   - natural habitat convert to agriculture land and urban area
   - disrupt ecosystem cause loss of biodiversity
   - deforestation lead to soil erosion
3. over exploration of natural resources
   - overfishing/ deforestation/ unsustainable harvesting of wildlife
   - local extinctions
4. pollution
   - human activity release pollutant such as chemical, heavy metal, plastic to environment
   - contaminating soil, water and air
   - disrupt ecosystem and harming wildlife

Question 6

method to control successful conservation

Answer 6

in-situ conservation–conserve animal and plants in their natural habitat
1. conserved area
- provide strict limit on building , hunting or other activity that affect plants and animal
- national park/ marine parks such as Yellowstone national park

ex-situ conservation–conservation of species outside their habitat
1. seed bank
- keep the seed dehydrated to prevent further damage
- seed will germinated every 5 year to check their viability
- exp. the royal botanic garden

2. botanic garden
   - collect, cultivation and display a wide range of plants labelled with botanical name
   - keep plant sample by seed, tissue culture and cloning
   - protect endangered plant species
3. gene bank
   - freeze and store sperm and unfertillized oocyte
   - for endangered species