Phloem Structure and Function

This video tutorial explains the structure and function of phloem in plants. It covers the role of phloem in transporting assimilates like sugars and amino acids from leaves to other parts of the plant. The video contrasts phloem with xylem, highlighting that phloem is a living tissue. It details the structure of sieve tube elements and companion cells, explaining their roles in phloem function. The video also describes the support structures within phloem, such as fibers and sclerods, which provide structural integrity.

What is the primary function of xylem vessels in plants?

• Carrying water and dissolved minerals

• Transporting assimilates

• Providing structural support

• Photosynthesis

What are the compounds called that are transported by phloem?

• Minerals

• Assimilates

• Lipids

• Proteins

Which statement is true about the movement of molecules in phloem?

• Molecules only move downwards

• Molecules do not move

• Molecules only move upwards

• Molecules can move both up and down

Which of the following is a characteristic of phloem tissue?

• Non-living

• Only transports water

• Contains lignin

• Living tissue

What is the function of sieve plates in phloem?

• To produce ATP

• To allow phloem sap to move between cells

• To store nutrients

• To photosynthesize

What is the role of companion cells in phloem?

• To transport water

• To store glucose

• To provide essential molecules to sieve tube elements

• To photosynthesize

What connects companion cells to sieve tube elements?

• Cell walls

• Chloroplasts

• Plasmodesmata

• Vacuoles

Which of the following is NOT found in phloem tubes?

• Companion cells

• Fibers

• Sieve plates

• Lignin

What provides support to phloem tissue?

• Lignin

• Fibers and sclerods

• Chlorophyll

• Xylem

How do fibers and sclerods differ in phloem?

• Fibers contain chlorophyll, sclerods do not

• Both are identical in shape

• Fibers are long and narrow, sclerods have various shapes

• Fibers are short and wide, sclerods are long and narrow