Plant Tissues, Organs & Systems

• The cuticle is a waxy waterproof coating on the surface of the epidermis which helps prevent water loss from plants.
• The epidermis is the outermost layer of cells that covers all plant parts
• Stomata are small openings found only on the underside of leaves that allow gases to enter or exit the leaf
• Stomata are small openings found only on leaves and stems. They allow gases to enter or leave the leaf but also allows water vapour to escape so they need to be closed at night when there's no photosynthesis happening
• Transpiration is the evaporation of water vapor through the stomata
• Guard cells control the opening and closing of stomata by changing shape due to turgor pressure
• How does closing its stomata help a plant?

  reduce water loss
• What is diffusion?

  Movement of particles from a high concentration to a low concentration down a concentration gradient and is a passive process
• Describe how water moves from roots to the leaves.

   

  Active transport in the xylem
• A plant has very few stomata on the upper surface of the leaf. Explain why this is an advantage to the plant.

  less water lost so it does not wilt
• Give three environmental conditions that would increase transpiration.

  hot

  dry

  wind
• Some plants produce fruits which contain glucose. Describe how you would test for the presence of glucose in fruit.

  use Benedict’s solution

  glucoses turns solution blue to orange
• TMV can cause plants to produce less chlorophyll. This causes leaf discoloration. Explain why plants with TMV have stunted growth.

  less photosynthesis due to lack of chlorophyll so less glucose made and less energy released for growth as glucose is needed for respiration so less amino acids for growth as glucose is needed for making amino acids
• Name the cells which control the size of the stomata.

  Guard
• Give one function of stomata

  To allow carbon dioxide to enter
• Very little water was lost when the lower surfaces of the leaves were covered in grease. Explain why

  the lower surface has most stomata which are now covered so water cannot escape
• What is meant by the transpiration stream?

  movement of water from roots via xylem to the leaves
•  

  Plant roots absorb water mainly by osmosis
• Plant roots absorb ions mainly by active transport.
• Tissue

  A group of similar cells that perform the same function.

  
• cell specialization/differentiation


  the process in which cells develop in different ways to perform different tasks

  
• stem cells

  unspecialized cells that retain the ability to become a wide variety of specialized cells

  
• Meristems


  Plant tissue that remains embryonic as long as the plant lives, allowing for GROWTH OF PLANT. Found at the root tips and the tip of the stem

  
• types of plant tissue

  dermal (epidermis), ground, vascular
• dermal tissue (epidermis)


  tissue of the plant that makes up the waxy outer layer of the plant

  
• plant organs

  roots, stems, leaves, flowers
• Plant Organ Systems

  shoot system and root system
• leaf


  The organ of a vascular plant where photosynthesis occurs

  
• stem

  supporting structure that connects roots and leaves and carries water and nutrients between them

  
• roots


  Absorbs water and minerals from the ground. Anchors plant in ground. Stores energy during hibernation.

  
• Photosynthesis

  Plants use the sun's energy to convert water and carbon dioxide into sugars and oxygen

  
• Epidermis (leaf)


  skin protecting leaf tissues; clear and waxy.

  
• palisade mesophyll

  photosynthetic tissue below the epidermis in a leaf.

  
• Chlorophyll


  Green pigment in plants that absorbs light energy used to carry out photosynthesis

  
• xylem and phloem


  two types of vascular tissue

  
• Xylem


  Nonliving vascular tissue that carries water and dissolved minerals from the roots of a plant up to its leaves

  
• Phloem


  Living vascular tissue that carries sugar and organic substances throughout a plant

  
• Stoma (leaf)


  Opening in the guard cells of the leaves that allows water and other gases in and out

  
• guard cells


  control the opening and closing of stoma

  
• root system

  All of a plant's roots, which anchor it in the soil, absorb and transport minerals and water, and store food.