1. Lima Bean Growth 2.
Secondary Root

2. Internal Anatomy: Plant Cells
Plant cells are different from animal cells because they have chloroplasts and large central vacuoles.
There are three basic types of plant cells:
Parenchyma cells:
Most common type of plant cell
Store starch, oil, and water
Help heal wounds and grow new parts
Collenchyma cells:
Provide support as the plant grows
Found in young tissues, leaves, and shoots
Sclerenchyma cells:
Strongest type of plant cell
Found in parts of the plant that are no longer growing

3. Internal Anatomy: Plant Tissues
Cells come together to form tissues.
There are three basic types of plant tissues:
Dermal tissues:
Cover the outside of the plant
Made of live and dead parenchyma cells
Live parenchyma cells become leaves and stems
Dead parenchyma cells become wood
Ground tissues:
Makes up the inside of the plant
Provides support and shape
Vascular tissues:
Transports water and nutrients to all parts of the plant
Made of hollow tubes called xylem and phloem
Xylem carries water and nutrients up from the roots
Phloem carries sugars from the leaves down to the rest of the plant.

4. Under The Ground: Root Structure
A seed begins by growing its roots. Roots are made up of 4 basic structures:
Vascular cylinder: the center of the root, made of xylem and phloem
Root hairs: tiny projections on root tips, where the most water is absorbed
Meristem: the point of root growth
Root cap: protects the growing part of the root as it pushes through soil
Vascular cylinder
Root hairs
Meristem
Root cap

5. Above the Ground: Germination
Germination is when seeds begin to sprout and grow.
As the stem grows it first lengthens the roots and stems. This is called primary growth.
Then the roots and stems begin to widen. This is called secondary growth.
The seed opens and we begin to see the cotyledon or embryonic leaves inside the seed.
If a plant has one cotyledon we call it a monocot.
If a plant has two cotyledons, we call it a dicot.
Our lima bean is a dicot.

6. Growing Tall: Leaves
Leaves grow from a plant’s stem. They have two main parts.
The blade is usually wide and flat. It’s job is to collect sunlight.
The petiole is a thin stalk. It’s job is to connect the blade to the stem.
The underside of a leaf has two important parts to help with photosynthesis.
The stomata is a tiny opening that allows in carbon dioxide and allows out oxygen during photosynthesis.
The guard cells around the stomata absorb water and also control the opening and closing of the stomata.