lesson 17 - energy, organisms & the biosphere Flashcards
what are the two main forms of energy?
kinetic energy and potential energy
which type of energy is associated with motion?
kinetic energy
what is the difference between thermal energy and kinetic energy if they are both associated with “movement”
kinetic energy is about the motion of an entire object, while thermal energy is about the motion of tiny particles inside a substance
what type of energy is energy waiting to be used?
potential energy
a type of potential energy that can be released in a chemical reaction
chemical energy
what does the first law of thermodynamics state?
energy can be transformed but not created or destroyed
what law of thermodynamics states: every energy transfer increases disorder in the universe
second law of thermodynamics
what is enthalpy (H)?
total energy content of a system
what happens when free energy (ΔG) is negative?
the process is spontaneous and does not require energy input
what happens when free energy (ΔG) is postive
the process requires an input of energy
which way does a system naturally move towards?
lower G (where ΔG = 0 or negative), because it means they have released excess energy and are now more stable.
how do autotrophs obtain energy?
they capture sunlight and convert it into chemical energy through photosynthesis
how do heterotrophs obtain energy?
they consume other organisms to obtain chemical energy
what is chemosynthesis?
a process where organisms in deep ocean environments use chemicals like hydrogen sulfide to generate energy instead of sunlight
why do organisms require continuous energy input?
to counteract entropy and maintain biological functions
what is thermoregulation?
the process by which animals maintain internal body temperature within a tolerable range
what is endotherm?
animals generate heat by metabolism
what is ectothermic?
animals get heat from enviornment
why do endotherms require more energy than ectotherms?
they generate their own heat, which requires more metabolic energy
what is metabolic rate?
the amount of energy an organism uses in a unit of time (how fast an animal burns energy)
how do we measure metabolic rate?
- oxygen consumed (breathing faster means more energy is being burned)
- more CO2 = animal is burning energy
- waste products (poop)
what are the factors that affect metabolic rate?
age, sex, size, activity level, temperature, and nutrition
what is standard metabolic rate (SMR)?
the energy an ectotherm uses at rest at a specific temperature
what is standard metabolic rate (SMR)?
the energy an ectotherm uses at rest at a specific temperature
why do smaller animals have higher metabolic rates than larger animals?
they lose heat faster and must burn more energy to stay warm
why do smaller atoms have higher entropy?
smaller atoms = more motion, more energy spreading, and more disorder
