Chapter 3B Flashcards
(35 cards)
What were the first organisms to transition from water to land?
Arthropods - insects, arachnids, and myriapods
What type of vertebrates also transitioned?
Amniote vertebrates such as reptiles, birds, and mammals
There are some organisms that still require water to maintain their lifecycles this includes?
Amphibians
How is being surrounded by water a benefit?
It is readily and easily accessible
Why do organisms need water in their systems?
Water supports the body
How does water support reproduction?
Allows the flagellated sperms to travel from one place to the egg.
How does water provide stable temperatures?
Unlike land the temperature of the water stays relatively constant - so organisms do not need to adapt to drastic climate changes.
How does water support metabolic wastes?
By removing it
How does water transmit sound?
Very well
How does water impact the metabolic rate?
It lowers the metabolic rate thus less energy is expended
What are 2 of the primary different physical properties between air and water?
Water is 100x more viscous and dense than air as a result more energy is expended to transport organisms and materials.
What is a temperature related challenge in water?
Organisms possess high thermal conductance therefore they can easily absorb heat from the environment.
How is dessication combatted?
By possessing a cuticle in plants and skin in animals.
How is gas exchange done on land?
Throught the stoma or the respiratory system.
How is gravity combatted?
Through certain morphological traits such as ribs and active transport.
How is sensory system developed?
Through the head or cephalization.
What is another way that organisms combat dessication?
Through a Loop of Henle which allows certain materials to pass through to the urine and other material to be reabsorbed by the body.
How does the Loop of Henle retain water?
In drier conditions the Loop of Henle elongates to allow water to be reabsorbed by the body and release concentrated urine.
What is aestivation?
This is a method of avoiding the dry season altogether that is done by African Lungfish. Whereby a bed of mucus is secreted and these fish lay in that bed and it hardens like a caccoon and they wait out the dry season.
What is parthenogenesis?
This is the development of the organism from an unfertilized egg.
Why can cold temperatures be detramental?
The components of the organism will not function accordingly for instance the proteins will denature and change in structure and if the structure changes so does the function.
How can the cold be tolerated?
- Hibernation
- Developing a higher sugar concentration and lower the freezing point
- Thermoregulation
- Behavioural adaptations
How can gametes be protected from dessication?
- Internal fertilization
- Mate finding
How can embryos be protected from dessication?
- Thick covering on the eggs
- Aminotic sac/membrane
