Conditions and Resources: The Physical Environment - Lecture 3 Flashcards
Define: Conditions
The physicochemical features of the environment. They are altered in the immediate environment of an organism, not consumed/used up by organism. i.e. Temperature, Humidity, and pH.
Define: Resources
The features of an environment that are consumed by organisms in course of maintenance/growth/reproduction. i.e. - photosynthesis uses solar radiation, carbon dioxide, water, and minerals - herbivores consume plants; carnivores consumer animals.
What causes temperature to vary seasonally?
Latitude.
What causes temperature to vary locally?
On land, altitude. In water bodies, depth and season.
What are the effects of temperature on organisms?
There is a linear relationship between temperature and growth and development, of which development frequently increases more rapidly than growth with increasing temperature.
What is the temperature-size rule?
Final size tends to decrease with rearing temperature.
What are the general implications of the temperature-size rule?
- Geographical size variation - Seasonal size variation - Seasonal variation in fecundity - Interactions between organisms in a changing climate affected
What are the main resources of primary producers: green plants?
- Radiant solar energy (heat and light) - Atmospheric carbon dioxide - Minerals (from soil) - Water
How does the absorption and reflection of photosynthetically active radiation (PAR) differ between different terrestrial plant canopies?
How does leaf angle affect the absorption of PAR in plant canopies?
- Angle of leaf affects quantity of radiation absorbed. Canopy leaves general grow at a greater angle to allow some sunlight through the canopy. Ground plants generally grow leaves perpendicular to the sunlight allowing them to absorb as much sunlight as possible.
