What are the 4 kingdoms?
Bacteria, Fungi, Plantae, Animalia
Animals are ____ and _____
Multicellular and Heterotrophic eukaryotes
2 concepts for Surface and volumes in animals:
Volume increases more rapidly than surface area
But large surface areas is critical for interaction with the environment
Basal Metabolic rate…
At rest the stomach is ___ and there is normal ___ and _____
empty, temperature and humidity
Basal metabolic rate can be measured by:
ml O2 consumed per hour per gram body weight
Explain the difference in basal metabolic rate between bigger and smaller animals
The bigger the animal the smaller the metabolic rate, the smaller the animal the bigger the metabolic rate
Large animals have less surface per kg which means less gas exchange
Basal metabolic rate two important factors?
- Surface to volume ratio is important
- Animals adapt to increase surface
Explain Salmon?
- salmon can breath through skin and gills (highly folded membrane, large surface)
Salmon can breathe through skin and gills but which predominates?
Young (small) salmon breath mostly through skin, older ones mostly through gills
Why? Surface to volume ratio!
What are the 5 adaptations to increase surface area
- Gas exchange (lung, gills, tracheoles)
- Nutrient uptake (intestine)
- Osmoregulation (kidney)
- Heat exchange (blood vessels)
- All these adaptations keep equilibrium (Homeostasis)
What is Homeostasis and why is it important?
- The ability to maintain a constant internal environment in response to environmental changes
- It is important as it allows to operate almost at optimal conditions under changing conditions
-Regulation to stay within acceptable ranges (which can change)
Examples of homeostasis
- Temperature
- Water and electrolyte balance, pH
- oxygen supply
- nutrient supply (glucose levels)
- blood pressure
What is 3 things required for homeostasis
- Sensor: detects status of internal or external environment
- Integrator: evaluates sensor information and decides if action is needed (setpoint = normal value)
- Effector: mechanism that helps restore desired condition
Examples of effectors (homeostasis)
- examples of effectors:
- Body temp below setpoint :Blood vessels constrict, Shivering, Chemical signals
- Body temp above setpoint: Blood vessels dilates, Sweat glands, Respiratory centres stimulate
Thermoregulation in Mammals relies on what?
- Relies on negative feedback
Three ways the body gains heat
- Blood vessels constrict: causes blood flow to lessen, heat loss decreases
- Shivering generates heat in muscles
- Chemical signals: stimulate increase in heat production in cells
Three ways that the body loses heat
- Blood vessels dilate: causes blood flow to increase, heat loss increases
- Sweat Glands: evaporation
- Respiration renters stimulated: panting increases heat loss
In Thermoregulation in mammals,
To gain temperature:
To lose termpartue:
- To gain temperature: Radiation from the sun or conduction from objects
- To lose temperature: Radiation out the body, evaporation or convection
Thermoregulatory Strategies…
How do animas obtain heat?
- An endotherm produces adequate heat to warm its own tissue
- An ectotherm relies on heat gained from the environment
Thermoregulatory Strategies…
Is an animal’s body temperature held constant?
- Homeotherms keep their body temperature constant
- Poikilotherms allow their body temperature to change depending on environmental conditions
More thermoregulatory Strategies… idk
- Many animals are in between these extremes
- May change, or be different in different body parts
Endotherms can do what and how?
Endotherms can warm themselves because their basal metabolic rates are extremely high
- Heat given off by high rate of chemical reactions is enough to warm the body
- Mammals and birds retain this heat because they have elaborate insulating structures such as feathers or fur
Ectotherms gain what and where?
Ectotherms gain heat directly from the environment and only generate a small amount of heat as a by-product of metabolism
Most heat is gained by ____ or _____
radiation or conduction
Endothermy and ectothermy are best understood as what?
understood as contrasting adaptive strategies
