3.3.1 Xylem and phloem

• The xylem is a type of vascular tissue in plants responsible for transporting water and mineral ions from the roots to the shoots
• What are the two types of cells that make up xylem?

  Vessels and tracheids
• Why are the walls of xylem vessels lignified?

  For strength and impermeability
• Tracheids are the main conduits for water and mineral transport in xylem.

  False
• What is the driving force behind the transpiration stream?

  Evaporation from leaves
• Match the concept with its description:

  Transpiration stream ↔️ Flow of water and minerals

  Cohesion-tension theory ↔️ Explains water movement in xylem
• Negative pressure in xylem pulls water upwards through the vessels.

  True
• What is the transpiration stream driven by?

  Evaporation from the leaves
• The lignified walls of xylem vessels provide strength and water impermeability
• Steps in the cohesion-tension theory

  1️⃣ Water evaporates from leaves

  2️⃣ Negative pressure (tension) is created

  3️⃣ Water is pulled upwards through xylem vessels
• Match the xylem cell type with its structure:

  Vessels ↔️ Long, continuous tubes

  Tracheids ↔️ Smaller, single-celled structures
• What is the primary function of phloem in plants?

  Sugar transport
• Phloem is composed of sieve tubes and companion cells
• Lignified walls in xylem provide strength and water impermeability.


  True
• Steps in the transpiration stream process

  1️⃣ Water evaporates from leaf surfaces

  2️⃣ Negative pressure is created in the xylem

  3️⃣ Water is pulled upwards due to tension

  4️⃣ Roots absorb water and minerals

  5️⃣ Water and minerals are transported through the xylem
• What organic nutrient is transported by phloem?

  Sugars
• Phloem is composed of two main cell types: sieve tubes and companion cells
• Phloem is responsible for transporting the organic nutrients produced by photosynthesis
• Xylem vessels are composed of living cells.

  False
• What is the driving force behind water movement in xylem?

  Transpiration
• What is the primary function of xylem?

  Water and mineral transport
• What type of vascular tissue is responsible for transporting water and mineral ions in plants?

  Xylem
• Xylem vessels have lignified walls for strength and water impermeability.

  True
• Match the plant tissue with its function:

  Xylem ↔️ Water and mineral transport

  Phloem ↔️ Sugar transport
• Vessels are long, continuous tubes that provide the main conduits for water and mineral transport
• What theory explains the upward movement of water in xylem vessels?

  Cohesion-tension theory
• Steps in the cohesion-tension theory:

  1️⃣ Evaporation from leaves creates negative pressure

  2️⃣ Water column is pulled upward through xylem

  3️⃣ Lateral water movement occurs via pits
• Phloem is composed of sieve tubes and companion cells.
• Match the vascular tissue with its primary function:

  Xylem ↔️ Water and mineral transport

  Phloem ↔️ Sugar transport
• Xylem transports water and minerals from the roots to the shoots
• Xylem transports water and minerals, while phloem transports organic nutrients
• What are sieve plates and where are they located?

  Perforated areas at sieve tube ends
• The primary function of phloem is to transport organic nutrients
• What role do companion cells play in sucrose transport?

  Maintain pressure difference
• Xylem is composed of living cells.

  False
• What structural adaptation allows efficient sugar transport in phloem?

  Sieve plates
• Xylem is composed of living cells called vessels and tracheids.

  False
• Xylem transports water and minerals via the transpiration stream
• What is the function of phloem in plants?

  Sugar transport
• Pits in the walls of xylem vessels allow lateral movement of water