Chapter 5: Plants - Biology Flashcards
(22 cards)
Meristematic Cells
- Constantly produce unspecialized cells which then become specialized
- “Permanent embryos” because of their lifelong ability to produce new cells which can become new organs, and tissues
- These specialized cells will come together to create the 3 types of tissues
Dermal Tissue
- Outermost layer
- Barrier between plant, and its external environment, and protects the inner tissues from damage
- Controls the gas and water exchange between plant and environment
Ground Tissue
- Contains cells that perform photosynthesis
- Other cells provide support to the plant’s body
Vascular Tissue
- Contains xylem and phloem
- Xylem: Transports water, and minerals from roots to other parts of the plant
- Phloem: Transports glucose from leaves to other parts of the plant
- Also provides physical support for the plant’s body
Draw all the tissues together (stem in root)
- Dermal Tissue (Outermost)
- Ground Tissue (Next layer)
- Vascular tissue (Inner portion containing phloem which surrounds xylem)
Draw all the tissues together (stem above soil)
- Dermal Tissue (Outermost)
- Ground Tissue (Next Layer)
- Vascular Tissue (Imagine 6 small circles evenly spaced out on a large circle, the small 6 circles are vasular tissues)
The Root
- To anchor plant in soil
- To collect water
- To transport water from the roots to the stem
- To store food
(Different tissues in the plant work together to accomplish this)
Auxin
- A plant hormone responsible for controlling the growth of cells below, and behind them
- Terminal bud (on top of them stem) produces the auxin which restrains the development of cells in lateral buds (right near the stem of every leaf), therefore plant grows upwards
- When terminal bud is removed, the signal to restrain the development of lateral bud is removed, meaning that the plant will grow laterally (from the sides)
Diagram of the root
From outermost to innermost:
1. Root hairs on epidermis (dermal tissue)
2. Cortex (part of the ground tissue system)
3. Endodermis (not epidermis which is dermal tissue)
3. Pericycle (Surrounds xylem, and phloem)
4. Phloem (surrounds xylem) - part of vascular tissue
5. Xylem - part of vasular tissue
The two types of root
Taproot, and Fibrous Root
The Leaf
- This is where photosynthesis occurs (in mesophyll of ground tissue)
- Vascular tissue carries the water needed for photosynthesis from the root up to the stem to the leaf
- Vascular tissue carries sugar created to the rest of the plant
Epidermis (leaf)
- Epidermis is for protection
- Epidermis has stomata controlled by guard cells
- Cuticle is a wax like layer on top of the epidermis that prevents water loss
Guard Cells (leaf)
- Allows gasses to move in, and out of the stomata
- These cells change their shape to control the opening, and closing of pores (stoma) in the leaf
Chloroplast
An organelle that contains chlorophyll that provides plant with its green colour, and aids in performing photosynthesis.
Chloroplast structure
Thylakoids contain chlorophyll molecules which can trap light. A stack of thylakoids is a granum (plural grana), and it is there where photosynthesis occurs.
- NOTE: Grana looks cylindrical in a diagram.
1. First chlorophyll (in thylakoid, and granum) traps light energy from the sun
2. Water enters from the roots, and oxygen gas exits
3. With the high energy molecules in the chloroplast, carbon dioxide enters, and glucose is created
Leaf Structure
Refer to diagram on “plant worksheet” but following parts include:
- Cuticle
- Dermal Tissue
- Stoma
- Guard Cells
- Upper, and Lower Epidermis
- Ground Tissue
- Palisade Parenchyma
- Spongy Parenchyma
- Collenchyma
- Vascular Tissue
- Xylem
- Phloem
- Vein
Functions of Stem
- Transports water, and nutrients throughout the plant
- Supports the leaves, and flowers
The Stem
- Epidermal tissue provides protective covering, allows for gas exchange, and reduces water loss
- Ground tissue provides the stem with strength and support
- Vascular tissue transports substances around the plant
The Flower
- Reproductive structure of the plant
- Function: Produces seeds through sexual reproduction
Male Reproductive
- Stamens is a male organ
- Anther produces pollen (sex cells)
- Filament is a long stalk of the stamens which supports anther
Female Reproductive
- Ovary: Holds the ovules (eggs)
- Ovules: Are eggs, and when they are fertilized they will develop into fruit or seeds
Fertilization
- When pollen, and egg unite the fertilized egg becomes a seed
- Seeds are surrounded by fruit or hard shell
- All of it starts of with meristematic tissue
- The unspecialized meristematic tissue differentiates to form parts of the flower
