Biology 1011 tricky topics Flashcards
What is the pericycle? Where can it be found ?
- gives rise to lateral growth of root
- found in the stele (within endodermis)
What is the integument? Where can it be found ?
- the sac within the ovary which surround the ovules etc
- develops into the 2n seed coat
What is plasmolysis?
Process in which water molecules move out of the cell, causing it to shrink
What is photophosphorylation?
- the transformation of ADP into ATP (in light reactions of photosynthesis)
What is photorespiration?
- when rubisco binds to O2 during times of low CO2
- wasteful, Creates CO2
What is positive pressure?
Pressure in the system greater than the surroundings
What is negative pressure?
ie: tension
- pressure potential is negative, air sucked in
Where is osmotic potential the greatest?
The roots
Where is pressure potential most important?
the stem
What are the gametangia? Where are they formed?
- formed on gametophyte
- sex organs: antheridium and archegonium, produce sex cells
What nourishes the conifer seed?
Megagametophyte
What are the states of pieces of conifer seeds ?
megagametophyte (n), seed coat (2n), Zygote (2n)
What nourishes the flower seed ?
the 3n endosperm
How many times does fertilization occur in the flower?
twice (double fertilization) –> 2 sperm cells bind to form a 2n zygote, 3n endosperm
(note that there is also a 2n seed coat formed by the integument)
What division is moss?
division Bryophyta
What are chlamydomonas?
from the division chlorophytes, green algae, do not undergo alternation of generations
- unicellular zygote which divides immediately
When did plants appear?
1500 million years ago