Q3 QE

• Chloroplasts contain chlorophyll and carry out photosynthesis.
• Land plants - Bryophytes, Pteridophytes, Gymnosperms, Angiosperms
• Vascular plants - Pteridophytes, Gymnosperms, Angiosperms
• Seed plants - Gymnosperms, Angiosperms
• Multicellular organs with important functions:

  ● Structural support

  ● Absorb water and minerals

  ● Store organic nutrients
• primary root is the main root that goes straight down into the ground, while lateral roots are the helper roots that spread out from the sides
• the primary root branches to form lateral which improve anchorage and water absorption.
• A taproot system consists of one main vertical root

  that gives rise to some large lateral roots, or branch roots.
• Monocots have a fibrous root system characterized by many thin lateral roots with no main root.
• MONOCOTS

  • 1 cotyledon
  • parallel veins
  • stem vascular bundles scattered
  • fibrous roots
  • petals in 3s
• Adventurous Roots
• Adventitious Roots

  Arise from an organ other than the roots

  Prop root - roots that are designed for extra support
• Prop roots grow out from the branches or stems of certain types of trees
• Storage Roots

  -Roots that stores food/sugar
• Pneumatophore

  Lateral roots that grow upward (negative geotropism)

  • Site for oxygen intake
• Negative geotropism means that instead of growing down towards the ground, something grows up or away from it.
• pneumatophores help the plants breathe by taking in air from above the water and sending it down to the roots. Like a snorkel tube for divers
• Buttress

  Extension of lateral surface roots that serves as an extension
• buttress roots as really big and strong lateral roots that spread out even further and grow thicker to give the tree extra support.

  DIFFERENCE FROM LATERAL ROOTS

  while lateral roots focus more on absorption, buttress roots specialize in anchorage, helping the tree stay firmly rooted in place
• “Strangling” Aerial Roots

  ● Roots that wraps itself around a host tree, effectively killing it
• while prop roots are generally helpful and beneficial for the tree they belong to, strangling aerial roots can sometimes have negative effects on other plants
• Nodes are like the spots on a stem where leaves, flowers, or branches would come out internodes are the straight sections in between where the stem stretches out and gets longer.
• Apical (terminal) and Axillary (lateral) buds are responsible for apical and lateral growth.
• apical buds are typically found at the very top of a stem or branch

  axillary buds are usually found along the sides where the leaves meet the stem
• Stolons

  ● Stems that branch from the main stem and grow horizontally on the ground or just under it

  ● Look like roots, but have nodes

  ● Example: Grasses
• Rhizomes

  ● Fleshy stems that typically grow under the soil and parallel to the surface

  ● Often serves as the primary region for storing food

  ● Example: Ginger
• Stolons are like long runners that crawl along the soil surface or just above ground, while rhizomes are like underground tunnels that spread out horizontally beneath the soil.
• Rhizomes are elongated stems that store food primarily in their nodes

  tubers are enlarged structures that store food in their swollen tissue.
• Tubers

  ● Thick, fleshy storage, structures that form on stolons or rhizomes

  ● Have no basal plate; all new shoots and roots form at nodes on their surface
• Bulbs

  ● Short stem with fleshy leaves that functions as a storage organ
• Corms

  ● swollen base of a stem with swollen stem base covered with scales
• Cladodes

  ● Flattened, fleshy, photosynthetic stems specialized to store water and may appear as leaves
• Tubers, are typically round or oval-shaped that grow at the ends of underground stems or branches and store food reserves in their swollen tissue.
• simple leaves are like one big leaf, and compound leaves are like lots of little leaves all stuck together.
• Modified Leaves

  Tendrils-cling

  ● Spines “prickly”-photosynthesis is carried out

  mainly by the fleshy stems

  ● Storage leaves-succulent plant leaves store water

  ● Reproductive leaves-little plantlets fall off and take

  root in the soil

  ● Bracts-look like petals attract pollinator

  Highly Modified Leaves - venus flytrap
• • Dermal Tissue: This is like the plant's skin, protecting it from the outside world.

  Keyword: Shield

  • Vascular Tissue: These are like the plant's highways, carrying water and nutrients from the roots to the rest of the plant.

  Keyword: Transport

  • Ground Tissue: This is like the plant's inner playground, where all the action happens, like making food and storing nutrients.

  Keyword: Playground
• DERMAL

  A tissue system that protects the soft tissues inside the plants

  In non-woody plants, the dermal tissue system consists of the epidermis

  A waxy coating called the cuticle helps prevent water loss from the epidermis

  In woody plants, protective tissues called periderm replace the epidermis in older regions of stems and roots

  Trichomes are small hairs or outgrowths of the shoot epidermis that can reduce water loss and reflect light; they are also used as insect defense
• VASCULAR

  • For transport of water and nutrients between roots and shoots
• VASCULAR

  • For transport of water and nutrients between roots and shoots
  • Composed of elongated conducting tubes bundled with sclerenchyma fibers and parenchyma
  • Two types: Xylem and Phloem
  • The vascular tissue of a root or stem is collectively called the stele

  ➔ The stele of the root is a solid central vascular cylinder

  ➔ The stele of stems and leaves is divided into vascular bundles
• XYLEM

  • It conducts water and minerals dissolved in it
  • Consists of two types that are dead in mature tissue

  1. Tracheids found in the xylem of all vascular plants

  ➔ Doesn’t have any perforations

  2. Vessel elements are common to most angiosperms but absent in gymnosperms

  ➔ Align end to end to form long micropipes called vessels

  ➔ Has perforations