BIOL371 ANIMAL THEME 3 EXAM QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS GRADED A++
Terrestrial lineages (3)
1. Arthropods: insects, arachnids, myriapods
2. Some vertebrates: amniote vertebrates (reptiles, birds, mammals)
3. Some we find on land still need water to complete lifecycle (Amphibians)
Living in water advantages (6)
1. relatively stable temperature
2. metabolic wastes removed
3. gases diffuse from water
4. sound transmits well
5. water supports the body
6. reproduction facilitated by flow, gametes don't dry out and exchanged in environment
Living in water disadvantages (2)
1. density and viscosity of water: cost of locomotion and visual range
2. limits metabolic rates: lack of available O2
Life in air (4)
1. Low heat capacity: extreme temperatures
2. low viscosity: air flows easily across a surface
3. O2 diffuses faster in air
4. less dense: gravity
, Life in water (4)
1. high heat capacity: stable thermal environment
2. universal solvent: dissolves molecules, transport molecules
3. high viscosity: strong intermolecular interactions
4. high density: pressure changes with depth
Challenges on land (6)
1. desiccation
2. rid of toxic wastes
3. gas exchange mechanism (breathing air)
4. requires weight supporting strategy
5. protective coating or internal structures
6. sensory systems and structures
Adaptations to prevent cells drying out (4)
1. need to maintain [ ] of body fluids
2. humidity inside animal > outside
3. loss of water by evaporation
4. balance between water loss and gain
Desiccation avoidance: mechanisms to reduce water loss (3)
1. skin/waxy cuticle
2. behavior
3. produce concentrated urine (loop of Henle): recover H2O and NaCl from urine, from
left to right, left=H2O, right=NaCl
Desiccation avoidance: mechanisms to replace water loss (2)
WITH COMPLETE SOLUTIONS GRADED A++
Terrestrial lineages (3)
1. Arthropods: insects, arachnids, myriapods
2. Some vertebrates: amniote vertebrates (reptiles, birds, mammals)
3. Some we find on land still need water to complete lifecycle (Amphibians)
Living in water advantages (6)
1. relatively stable temperature
2. metabolic wastes removed
3. gases diffuse from water
4. sound transmits well
5. water supports the body
6. reproduction facilitated by flow, gametes don't dry out and exchanged in environment
Living in water disadvantages (2)
1. density and viscosity of water: cost of locomotion and visual range
2. limits metabolic rates: lack of available O2
Life in air (4)
1. Low heat capacity: extreme temperatures
2. low viscosity: air flows easily across a surface
3. O2 diffuses faster in air
4. less dense: gravity
, Life in water (4)
1. high heat capacity: stable thermal environment
2. universal solvent: dissolves molecules, transport molecules
3. high viscosity: strong intermolecular interactions
4. high density: pressure changes with depth
Challenges on land (6)
1. desiccation
2. rid of toxic wastes
3. gas exchange mechanism (breathing air)
4. requires weight supporting strategy
5. protective coating or internal structures
6. sensory systems and structures
Adaptations to prevent cells drying out (4)
1. need to maintain [ ] of body fluids
2. humidity inside animal > outside
3. loss of water by evaporation
4. balance between water loss and gain
Desiccation avoidance: mechanisms to reduce water loss (3)
1. skin/waxy cuticle
2. behavior
3. produce concentrated urine (loop of Henle): recover H2O and NaCl from urine, from
left to right, left=H2O, right=NaCl
Desiccation avoidance: mechanisms to replace water loss (2)
