15. (a) (i) Name the growth response in which plant stems grow towards light - Leaving Cert Biology - Question 15 - 2022

Plants benefit from increased light intensity primarily by enhancing the process of photosynthesis. This leads to greater production of glucose, which serves as food for the plant, promoting overall growth.

Another environmental factor that regulates plant growth is day length, or photoperiod, which affects flowering and other growth responses.

The tissues labelled are:

• A: Dermal
• B: Ground

The functions of the tissues are:

• Tissue A (Dermal): Provides protection against water loss and pathogens.
• Tissue B (Ground): Functions in support and storage of substances.

The structure labelled C is the vascular bundle.

The cells found in structure C that transport water are xylem vessels, specifically tracheids.

One way a section through a root would differ from the section above is that roots have a protective structure called root hairs that aid in absorption of water and nutrients, which is not present in the stem section.

The diagram represents a section through a dicotyledonous plant stem because the arrangement of the vascular bundles is in a ring, which is characteristic of dicots.