1S1: Plant Life Cycle

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Today we’re going to learn about the plant life cycle and plant parts.

  • What do you already know about plants? (Brainstorm and write their ideas on the board or have some kids come up and draw a plant on the board.)
  • What do plants need to grow? (sunlight, water, nutrients in the soil, and air/CO2)
  • What do plants grow from? Start off with examples (analogies) like humans from babies, cats from kittens, etc. Call on students until they answer that plants come from seeds.


Sun – outstretched arm with pointed finger like a sun’s ray

Rain – wiggle fingers as arms move downward

Air – arms move back and forth (or bodies run back and forth for a storm), accompanied by a whooshing sound

Plant Parts:

Seed – curl up in a ball on the floor. The seed has all the nutrients that plant needs to start sending up shoots and sending down roots. Send up a hand (shoot) and send out a leg (root). Uncurl and kneel-you’ve sprouted

Stem – Stand (or kneel) straight and tall. The stem provides the structural support for the plant so it doesn’t fall over. It also moves water and nutrients from the roots upward and sugars from the leaves downward.

Root – Wiggle your fingers-you grow lots of leaves. Stand up (feet together)- you grow taller. Spread feet apart- you spread out lots of roots. Wiggle your toes- you grow lots of little roots (rootlets). ‘Slurp, slurp’- your roots drink up water from the ground.

Leaf – Hold hands flat and palms forward on either side of face. Leaves are the food producing centers where they transform sunlight, water and air into sugar – food for the plant. They turn towards sun rays (act out a sun ray), and flutter in the wind (act out wind).

Flower – Hold hands with fingers spread wide over face. Hands are petals which then open and spread outward from face. Flower is the first step in making a new plant. The flower needs to get pollinated in order to produce fruit and seeds. A bee buzzes around and pollinates the flower (slap hands with kids). Uh, oh. Start scratching all over, you’re being attacked by insects and fungi.

Fruit – Form a large circle with arms over head. It has seeds inside (represented by the head). The fruit is often eaten by some animal and the seeds then get moved around by the animal to start a new plant. Or the fruit falls on the ground and the seed eventually comes out of the rotting fruit. Have fruits get plucked and eaten or fall and splat on the floor. Stick up one arm- a new seed sprouts from the ground where your tomato fell.

Questions about the lifecycle

  1. What do plants need to live? (Light, Air, Water, Soil)
  2. Why do we have the bee as part of the tomato plant lifecycle? (it moves pollen from one flower to another and pollinates the flowers. The flowers become fruit after they get pollinated)
  3. Can you think of anyway that humans fit into this cycle? (plant, eat fruit, maintain plants)
  4. Can someone re-tell the plant lifecycle in their own words?


Take in soaked Lima Beans and show/explain different parts of the seeds.

Why do seeds need a coat? Explain that seeds have coats for the same reason we wear them—protection. We wear coats in the rain or when it’s cold to protect us from the elements.

The seed coat protects the inside of the seed which is where the baby plant is. Show the students how to split the seed in half. Make sure they open the rounded side, as not to damage the root and other internal plant structure. Look at the poster and find the same parts in the actual seed.

a) The biggest part of the seed is the cotyledon. The cotyledon is where food is stored, which feeds the baby plant before it reaches the light. Remind the kids that sunlight makes the plants grow, but when they are still underground, they need a different source of food. So each seed has its own little refrigerator underground: the cotyledons.

Q: Does the seed need the cotyledons once it has poked above the ground?
A: No, because the sunlight is now the plant’s food.

b) Look carefully on one end of the seed. You can see the beginnings of a root (technically the radical).

Q: What does the root do?
A: The little root will push the plant through the soil. It also soaks up water and nutrients in the soil.

Q: Which direction does the root go? Why?
A: It usually goes down in the soil, so that it can find water.

c) Next to the root, you can see small leaves.

Q: What do leaves do?
A: When they poke above the ground, they collect sunlight which makes them grow. The first leaves are usually bigger than the latter ones because they need to collect lots of sunlight.

*If time permits, go over the lima bean sequencing cards.

Activity_Order_Seed_Cards.pdf246.45 KB
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