Plant Structure - Lecture notes Chapter 4 PDF

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Its a combination of lecture notes and the text book notes. Great review....

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Plant Structure  Function of a Xylem and Phloem o

Xylem: transport water needed for photosynthesis to the cell into mesophyll

o

Phloem: transport sugar produced through photosynthesis to the rest o the plant

 Difference between a fibrous root system and taproot systems in terms of structure and water absorption o

Tap root consist of a large single root that grows straight down with several smaller roots

o

Fibrous root is made of several to many roots of similar size

 Which root system helps prevent soil erosion: Fibrous Roots  The xylem and phloem are made up of vascular tissue The upper and lower epidermis are made up of dermal tissue Meristem: undifferentiated thus they are the stem cells of the plant or cells without a “job” yet Plants begin life as an Embryo.  Seeds are the result of sexual reproduction in plants  An embryo is the earliest stage of development  Cells actually differentiate into roots cells that develop into the roots, stem, and leaves  Seed coat: the seed has a protective outer layer  Endosperm: food supply Seed Dispersal  Seeds may be dispersed or scattered in many ways different ways  Ex: o

Spade

o

Sunlight

o

Water

o

Nutrients

Seed Democracy  Not all begin grow immediately, some need the right environmental conditions to stimulate growth  Seed are able to survive for months, even years in a dormant (sleep) state

Seed Germination  When most seeds germinate, a tiny root tip breaks through the seed coat and Grows downward into the soil  Soon, tiny root hair push through spaces in the soil, to absorb water and minerals

Plant Growth Increases Length and Width of Plant  Plants continue to grow in length, called primary growth, and diameter, called secondary growth.  Growth occurs through rapid cell division is tissue called meristems.  Meristem cells are undifferentiated (thus they are the stem cells o the plant) (or cells without a “job” yet)

Tissue

Meristem

Tissue

Primary Growth o

Makes the roots grow downward and stems grow taller

Secondary growth o

Increase the width of stems and roots

Plants have three main tissue systems 1. Dermal Tissue o

Makes up the outer covering of the plant

o

Cells in the dermal tissue are called epidermal cells

o

Epidermal tissue protects the plant from the outside environment

o

Epidermal cells secrete a waxy substance called the cuticle, which protects the plant from water loss

o

Root hairs increase the surface area for the absorption of water

2. Vascular Tissue o

Responsible for transporting water and nutrients through the plnt

o

Xylem (function): support of plant and transport water, and dissolve nutrients from the roots upward to another parts of the plant

Organ

o

Phloem (function): tissue transport sugar made from photosynthesis to other parts from the plant

3. Ground Tissue o

Makes up the bulks of the plant

o

Provide support for roots and stems

o

Packed with cells containing chloroplast, which are responsible for photosynthesis in the plant

 Level of organization from the simplest to most complex in a multicellular organism o

Organelle  Cell  Tissue  Organ  Organ System  Organism

 Examples of what level of organization each plant structure belongs to: o

Apple tree: organism

o

Meristem: organelle

o

Guard cell: organ system

o

Xylem & phloem: cell

o

Leaf: organ

o

Stem: tissue

Definition  Independent variable: the change in a experiment  Dependent variable: something that stays the same  Constant: something that control or makes the experiment work  Autotroph: sunlight helps plants to reproduce food for themselves  Heterotroph: organism that consume food...