Biology Flashcards
What structures arise in flowering plants?
Roots, stems, leaves, flowers, fruits, and seeds.
What are the terms associated with plant development?
Seed, seedling, plantlet, mature plant.
Do trees continue to grow over time?
Yes, trees continue to increase in height or girth over a period of time.
What happens to leaves, flowers, and fruits of a tree?
They have limited dimensions and appear and fall periodically.
What precedes flowering in a plant?
The vegetative phase.
What are all cells of a plant descendants of?
The zygote.
What is the first step in the process of plant growth?
Seed germination.
When does a seed germinate?
When favorable conditions for growth exist in the environment.
What happens to seeds in the absence of favorable conditions?
They do not germinate and enter a period of suspended growth or rest.
What resumes when favorable conditions return for seeds?
Metabolic activities and growth.
What factors govern and control plant developmental processes?
Both intrinsic (internal) and extrinsic (external) factors.
What is depicted in Figure 13.1?
Germination and seedling development in bean.
What is growth in plants?
Growth can be defined as an irreversible permanent increase in size of an organ, its parts, or an individual cell.
What characterizes plant growth?
Plant growth is unique because plants retain the capacity for unlimited growth throughout their life.
What are meristems?
Meristems are regions in plants where cells have the capacity to divide and self-perpetuate.
What is the open form of growth?
The open form of growth is when new cells are continuously added to the plant body by the activity of the meristem.
What are the two types of apical meristems?
The two types of apical meristems are root apical meristem and shoot apical meristem.
What is secondary growth in plants?
Secondary growth is the increase in the girth of the organs caused by lateral meristems like vascular cambium and cork cambium.
How is growth measured at a cellular level?
Growth is measured by quantities proportional to protoplasm increase, such as fresh weight, dry weight, length, area, volume, and cell number.
What is the growth rate of a maize root apical meristem?
One single maize root apical meristem can give rise to more than 17,500 new cells per hour.
What are the three phases of growth?
The three phases of growth are meristematic, elongation, and maturation.
How is the growth of a pollen tube measured?
The growth of a pollen tube is measured in terms of its length.
What denotes the growth in a dorsiventral leaf?
An increase in surface area denotes the growth in a dorsiventral leaf.