Lesson 27: energy flow in
ecosystems

focus on inquiry

the food chains and food webs that appear in this lesson and in other books have already been
worked out. to construct a food chain or food web, you need to identify which organisms live in an
environment and how each organism obtains energy within that environment.

some organisms are suited to life in more than one type of environment. such an organism may have
a different place in the food chain in each environment. for example, coyotes live in both deciduous
forests and deserts. very different plants and animals make up these two ecosystems. therefore, a
food chain or food web that includes a coyote living in a desert may be very different from one that
includes a coyote in a forest. migratory birds are often suited to life in different ecosystems. the
winter home, or habitat, of a migratory bird may be very different from its summer habitat.

identify a species of migratory bird or other animal that can live in more than one type of
environment. research what the animal eats in each ecosystem and whether other organisms prey on
it in those environments. gather enough information to draw two different food chains or food webs
that include the animal.

the equation above shows how temperature f, measured in degrees fahrenheit, relates to a temperature c, measured in degrees celsius. based on the equation, which of the following must be true?

a temperature increase of 1 degree fahrenheit is equivalent to a temperature increase of

5

9

degree celsius.

a temperature increase of 1 degree celsius is equivalent to a temperature increase of 1.8 degrees fahrenheit.

a temperature increase of

5

9

degree fahrenheit is equivalent to a temperature increase of 1 degree celsius.

a) i only

b) ii only

c) iii only

d) i and ii only

i am going to guess that it is co2.

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.