Xylem and Phloem Outline Xylem and Phloem definition

Xylem and Phloem

Outline �Xylem and Phloem definition �Xylem and Phloem Structure �Xylem and Phloem Function �Xylem vs. Phloem �References

Outline �Xylem and Phloem definition Xylem and Phloem Structure Xylem and Phloem Function Xylem vs. Phloem References

Xylem and Phloem definition � Xylem is a type of tissue in vascular plants that transports water and some nutrients from the roots to the leaves. �Phloem is the other type of transport tissue; it transports sucrose and other nutrients throughout the plant.

Outline Xylem and Phloem definition �Xylem and Phloem Structure Xylem and Phloem Function Xylem vs. Phloem References

Xylem and Phloem Structure

Xylem and Phloem Structure �Structure of the xylem tissue

Xylem and Phloem Structure �Structure of the phloem tissue

Outline Xylem and Phloem definition Xylem and Phloem Structure �Xylem and Phloem Function Xylem vs. Phloem References

Xylem and Phloem Function �Xylem Function : - Xylem vessels carry water and minerals from the roots to the leaves .

Xylem and Phloem Function �Phloem Function : - The function of the phloem tissue is to transport food nutrients such as sucrose and amino acids from the leaves and to all other cells of the plant, this is called translocation.

Outline Xylem and Phloem definition Xylem and Phloem Structure Xylem and Phloem Function �Xylem vs. Phloem References

Xylem vs. Phloem �Xylem : - Xylem cells are dead, elongated and hollow. - Two different types of cells are known to form the xylem in different plant groups: tracheids and vessel elements. � Tracheids are found in most gymnosperms, ferns and lycophytes �vessel elements form the xylem of almost all angiosperms.

Xylem vs. Phloem 1. Tracheids : � Tracheids are long thin cells that are connected together by tapered ends. The tapered ends run alongside each other and have pits that allow for water to travel from cell to cell. � Their secondary cell walls contain lignin – the compound that creates wood. The lignin in tracheids adds structural support to the xylem and the whole plant.

Xylem vs. Phloem 2. Vessel elements : � Vessel elements are shorter and wider than tracheids and are connected together end on end. � The ends of the cells contain what are known as ‘perforation plates’. � The perforation plates have a number of holes in their cell walls which allows for water to travel freely between cells.

Xylem vs. Phloem �Phloem : � The phloem is made from cells : 1. sieve-tube members 2. companion cells

Xylem vs. Phloem 1. Sieve-tube members � Sieve-tube members are living cells that create chains of cells running the length of the plant. � The cells of sieve-tube members are missing some important structures such as a nucleus, ribosomes and a vacuole which is where companion cells come in.

Xylem vs. Phloem 2. companion cells: The companion cells run adjacent to sieve -tube members and are connected by a number of channels called ‘plasmodesmata’. � Companion cells are not lacking in any vital organelles and their nucleus and ribosomes serve both the sieve-tube member and itself. � The companion cell can sometimes also deliver sugars and other substances into the sieve-tube members from neighboring cells. �

Outline Xylem and Phloem definition Xylem and Phloem Structure Xylem and Phloem Function Xylem vs. Phloem �References

References www. presentationszone. com https: //biologydictionary. net http: //biology-igcse. weebly. com https: //basicbiology. net