1 Observing Daphnia
Vocabulary
Concepts and Skills
daphnia a tiny animal
related to shrimp that lives
in fresh water
• Students predict the effect of nonliving factors on aquatic
ecosystems.
ecosystem all the living
and nonliving things that
interact with each other in
an environment
• Students explain the functions of structures found in daphnia.
habitat the place where
an organism lives
Planning
organism any living thing
population all of the
organisms of the same
type living in the same
place at the same time
Inquiry Focus
Observe When students
observe, they gather information using their senses
and tools such as hand
lenses.
• Students use appropriate technology to observe daphnia.
• Students measure and record data in metric units.
Materials
Student Resources
• aquariums with lids
• 1.1 Vocabulary
• cups
• daphnia
• 1.2 The Organisms Are
Coming!
• depression microscope slides
• 1.3 Aquarium Log
• droppers
• 1.4 Observing Daphnia,
Pages 1 and 2
• lamp with light bulb
• magnifiers
• metric rulers
• *microscopes or video/
microscope projection system
• 1.5 Counting Daphnia
Populations
• 1.6 Daphnia Body Parts
• 1.7 Section 1 Assessment
• vials with lids
• *water
*Not provided in kit
In Advance
• Order daphnia three to four weeks before starting Section 1 as
explained in Getting Started p.T7. Plan to start the investigates the
day the daphnia arrive.
• When algae arrives with the second coupon add a cup of algae
water to aged water in a quart jar and leave it in a sunny window
to promote growth. This green water will be used in Section 6.
• For Investigate 3 If you do not have access to a microscope check
with your middle school to see if they will share some with you.
You need 20x to 100x power.
2 • EXPERIENCE SCIENCE
Science Background
Evaporation Evaporation is the process wherein water changes
state from a liquid to a gas. Evaporation is one of three processes
that make up the water cycle. The water cycle refers to the constant
cycling of water from Earth’s surface to the atmosphere and back
again. The other two processes in the water cycle are condensation
and precipitation. During condensation, water changes state from a
gas to a liquid. During precipitation, liquid or frozen water falls to
Earth’s surface as rain, snow, sleet, or hail.
Scientific Tools Compound microscopes use eyepiece lenses and objective lenses to magnify objects. Images are viewed
through the eyepiece lenses, which are contained in one or two
tubular structures. The objective lenses often have different levels
of magnification. The total magnifying power of a microscope is
equal to the combined powers of both types of lenses. For example,
a microscope that has an eyepiece lens with a magnifying power
of 103 and an objective lens with a magnifying power of 433 has a
total magnification of 4303.
SECTION 1 OBSERVING DAPHNIA • 3