← Back to course
Grow It 3-5 / Week 08 / Tuesday
2/6
Week 08 · Traits and Variation

Tuesday

No two the same
// Why no two bean plants are exactly alike
⏱ about 15 min

Tuesday: No Two the Same

Raven pours a handful of dry beans onto a plate. "These all came from the same kind of plant," she says.

Rocket shrugs. "So they are all the same."

Raven smiles. "What do you notice if you line them up?"

Nova shines a gentle light on the plate. "Measure before you decide," she says.

Rocket grabs a ruler.

What is variation?

Living things of the same kind are not all the same.

Small differences among them are called variation.

Beans from one bag can vary in length, color and spots.

Different organisms vary because they inherit different information from their parents.

Your bean line-up

  • Five dry beans of one kind
  • A ruler with centimeters
  • A plate or paper towel
  • A pencil and paper
Safety first
The beans are for measuring only. Never put a bean in your mouth.
Keep beans away from little kids and pets.
Wash your hands when you finish.
  1. Lay the five beans in a row.
  2. Give each bean a letter: A, B, C, D, E.
  3. Measure each bean's length in centimeters.
  4. Write the length and color in the table.
  5. Circle the longest bean and the shortest bean.
BeanLength (cm)Color or spots
A
B
C
D
E
Were all five of your beans exactly the same length? Type yes or no.
WHY THIS EXERCISEMost groups of beans show variation, small differences in size.

Variation in seedlings

Seedlings from the same seed pack also show variation.

One might have bigger leaves. Another might have a thicker stem.

Variation is normal. It is part of being alive.

SPOT THE VARIATION
  • Read the question.
  • Tap your answer.
Ten pea plants grow from one seed pack. What will you probably see?
Two corn plants of the same kind have different numbers of leaves. What is this called?
StatementTrue or false?
Beans of one kind can vary in length.?
Variation means every plant is the same.?
Seedlings from one pack can have different size leaves.?
Measuring helps us see variation.?
WHY THIS EXERCISEMeasuring shows small differences among living things of one kind.
Small differences in a group are called ____.
We measured bean length in ____.
Try it
Check your bean plant.
Measure its height in centimeters from the soil to the top.
Write the number in your plant log.

Excellent measuring! Tomorrow we find out how light, water and space change a plant.

← Monday