40+ Flashcards
(75 cards)
convergent evolution
reflects different species’ adaptations to a similar environmental challenge
Exchange rate is proportional to the organisms’ ______
surface area to volume ratio
______ the interchange of O2 and CO2 between an organism and its environment,
gas exchange
open systems
Blood is not contained in blood vessels
• Nutrient rich blood “open” in the body cavity
• a heart pumps fluid through open-ended vessels to bathe tissue cells directly.
closed systems
Blood contained in blood vessels
• a heart pumps blood, which travels through arteries to capillaries to veins and back to the heart.
Open circulatory system in which fluid called ______ is circulated into the spaces surrounding the tissues and organs
hemolymph
Gas exchange in spiders occurs in respiratory organs called
book lungs
Most modern cheliceriforms are_____ , which include spiders,
scorpions, ticks, and mites
arachnids
Close circulatory system gas exchange occurs in three stages:
- Oxygen intake (eg. Breathing with lungs, or water over gills)
- transport of gases by the circulatory system, and
- exchange of gases with body cells: Body tissues take up O2 from the blood and release CO2 to the blood.
A fish’s two- chambered heart pumps blood in a
single circulation.
Land vertebrates have _____ with a _____ and a ______
double circulation; pulmonary; systemic circuit.
Amphibians and many reptiles have_____ hearts
three- chambered
Birds and mammals have _____ hearts
four-chambered
thermoregulation
Process by which animals maintain an internal temperature within a tolerable range
_____ animals generate heat by metabolism
• More energetically costly
• Eg. Birds and mammals
endothermic
______ animals gain heat from external sources
• Typically tolerate a greater variation in temperature range
• Eg. most invertebrates, fishes, amphibians, and non-avian reptiles
ectothermic
The body temperature of a _____ varies with its environment, while that of a _____ is relatively constant
poikilotherm; homeotherm
Five general adaptations help animals thermoregulate:
– Insulation – Circulatory adaptations – Cooling by evaporative heat loss – Behavioral responses – Adjusting metabolic heat production
Vasodilation
blood flow in the skin increases, facilitating heat loss
Vasoconstriction
blood flow in the skin decreases, lowering heat loss
______ blood is warmed via heat transfer
Countercurrent exchange
_____ determines how much food it needs and is related to the animal’s size, activity, and environment.
bioenergetics
The amount of energy an animal uses in a unit of time is called its _____
metabolic rate
Body size influences _____
metabolic rate