Big Idea
Science Standard 7.1.d:
Students know that mitochondria liberate energy for the work that
cells do and that chloroplasts capture sunlight energy for photosynthesis.
Paraphrase:
Students will know how plants capture sunlight energy for photosynthesis.
Big Idea
 photosynthesis: The process by which a cell captures energy
in sunlight and uses it to make food.
 autotroph: An organism that makes it’s own food.
 heterotroph: An organism that cannot make it’s own food,
including animals such as the zebra, and the lion.
 pigment: colored chemical compounds that absorb light.
 chlorophyll: the main photosynthetic pigment in
chloroplasts.
 stomata: small openings on the undersides of leaves.
 the term photosynthesis comes from the Greek words photo,
which means “light,” and synthesis, which means “putting
together.”
 Nearly all living things obtain energy either directly or
indirectly from the energy of sunlight captured during
photosynthesis.
 Plants manufacture their own food through the process of
photosynthesis.
 an organism that makes it’s own food is known as an
autotroph. (grass, plants)
 an organism that cannot make it’s own food is called a
heterotroph. (lions, zebras, etc)
Many heterotrophs obtain food by eating other organisms.
Some heterotrophs ,such as fungi, absorb their food from
other organisms.
Stage 1 : Capturing the Sun’s Energy
 involves capturing the sun’s energy in sunlight
In plants, this process occurs mostly in the leaves
Light is absorbed by the pigments ( green organelles inside plant
cells that absorb light)
The main photosynthetic pigment in chloroplasts is chlorophyll.
Chlorophyll captures the light energy and uses it to power the
second stage of photosynthesis.
Stage 2 : Using Energy to make food
 the cell uses captured energy to produce sugars
The cell needs two raw materials for this stage: water & carbon
dioxide
Roots absorb water from the soil, and moves up through the
plants stem to the leaves.
Carbon dioxide enters the plant through small openings on the
undersides of the leaves called stomata
Once in the leaves the water and carbon dioxide move into the
chloroplasts.
Inside the chloroplasts, the water and carbon dioxide undergo
chemical reactions. The reactions are powered be the energy
captured in the first stage. The products of these reactions are
SUGARS and OXYGEN.
Write down two questions you have about this
chapter!
Plants trap energy from sunlight during a process called
photosynthesis and uses that energy to make sugars. Plants
later break down those sugars, releasing the energy for cell
use. The leaf has stored food that the plant made using
energy from the sun. The substances that are needed for
photosynthesis are carbon dioxide and water. The
substances that are produced during photosynthesis are
sugar and oxygen.
 “The Cell in its Environment”
Worksheet #1-112