Environmental Science Duckweed Lab Environmental Science

Warm Up We will be starting our duckweed lab today. Over the next few weeks we will be observing it. Make a prediction about your duckweed population. (Use complete sentences)

Objective Students will understand factors that affect population growth Students will identify characteristics of population growth curves

Pre-lab Questions What factors are associated with changes in a population? What do you know about the human population?

Key Terms Carrying Capacity- maximum population size of a species that and environment can hold Expediential Growth- population grows quickly, has not reached the carrying capacity. Closed System- nothing can go in or out of this system (nutrients, organisms) Ex. Island (control) Give me another example Open System- no boundaries, things (nutrients, organisms) come and go Ex. Yellow Stone National Park (no control)

What is duckweed? Lemna minor Small aquatic plant Floats of the surface of water Food source for some organisms Very fast growing Reproduces by budding

Duckweed Diagram Frond Bud* Frond (leaf like structure) Root *Vegetative Budding (asexual reproduction)- reproduces itself

Procedures Write your name neatly on your plastic container Measure 400 mL of water Pour the water into your plastic container Your instructor will give you your duckweed frond colony Mark your water level on your cup with your marker Count your duckweed plants Complete Data Table 1. Observations Write a hypothesis