Tree Biology and Physiology Flashcards
7 cards from real ISA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Tree Biology and Physiology flashcards as text
What is the significance of the 'turgor pressure' within plant cells?
Answer: It maintains cell rigidity and drives cell expansion during growth
Turgor pressure, caused by water entering the vacuole osmotically, pushes the cell membrane against the wall, maintaining cell rigidity and providing the force for cell expansion and elongation.
What is the term for the zone of undifferentiated meristematic cells at a root or shoot tip?
Answer: Apical meristem
The apical meristem is the zone of actively dividing, undifferentiated cells at the tip of each root and shoot that drives primary growth in length.
How does a tree's stem diameter increase over time?
Answer: Through activity of the vascular cambium adding secondary xylem and phloem
Secondary growth and diameter increase result from the vascular cambium, a lateral meristem that adds layers of secondary xylem inward and secondary phloem outward each growing season.
Which of the following best describes 'compartmentalization' (CODIT) in tree wound response?
Answer: Creation of chemical and structural boundaries to limit decay spread
Compartmentalization of Decay in Trees (CODIT) describes how trees form chemical and physical barriers (walls 1–4) to limit the spread of pathogens and decay from a wound.
What role does lignin play in wood cell walls?
Answer: Adds rigidity and decay resistance to cell walls
Lignin is a complex polymer deposited in secondary cell walls that provides compressive strength, rigidity, and resistance to microbial degradation.
What is 'etiolation' in trees or seedlings grown under insufficient light?
Answer: Abnormal elongation of stems and pale coloration due to low light
Etiolation is the elongated, pale, and weak growth that occurs when plants are grown in insufficient light, as they stretch toward the light source while producing less chlorophyll.
Which nutrient deficiency is most commonly associated with interveinal chlorosis on young (new) leaves?
Answer: Iron
Iron deficiency causes interveinal chlorosis on young leaves because iron is immobile in the phloem and cannot be reallocated from older tissues to new growth.