Botany Flashcards
What are some characteristics of plants?
- Plants undergo photosynthesis
- Plants are composed of Eukaryotic cells
- Most plants are multicellular
- Plant’s are sessile
- Most plants have vascular tissue
- Plants have true leaves, true stems, and true roots
What is the definition of sessile?
The opposite of mobile
What two groups can Plantae be broken into?
Non-Vascular and Vascular
What is an example of a non-vascular plant?
D. Bryophyta (Moss)
What are the two groups of Vascular plants?
Spermatophyta (seeded) and Cryptogamae (non-seeded)
What is an example of a cryptogamae plant?
D. Pteridophyta (ferns)
What are the two groups of Spermatophyta?
Gymnosperms (naked seeds) and Angiosperms/Magnoliophyta (vascular seeds)
What is an example of a Gymnosperm?
D. Coniferophyta (coniferous trees)
What is an example of an angiosperm?
Acer rubrum (red maple tree)
What’s a short day plant?
A plant that flowers during spring or fall
What’s a long day plant?
A plant that flowers during the summer
What is phytochrome?
A pigment and hormone that controls flowering. It reacts to the full spectrum of light but favours red light. Phytochrome exists in the forms Pr and Pfr.
What is the function of Pfr in short day plants?
It inhibits flowering. Due to the lower levels of light compared to that of the summer, phytochrome causes short day plants to flower during the spring/fall.
What is the function of Pfr in long day plants?
It stimulates flowering. Due to the higher levels of light compared to that of the spring/fall, phytochrome causes long day plants to flower during the summer.
Where is phytochrome found in a plant?
It is found in the leaves and activates genes like a steroid hormone.
What is the general term for undifferentiated embryonic tissue in a plant?
Meristem
What is the term for meristem tissue at the tips of plants?
Apical meristem
Plants usually grow from the _____.
Tips
In a seed, what are the three types of tissue that the meristem differentiates into?
- Protoderm
- Procambium
- Ground Meristem
What is the function of protoderm tissue?
It forms the bark or outer layer
What is the function of the procambium tissue?
It forms the vascular tissue
What are the three types of specific cells that make up ground meristem?
Parenchyma
Sclerenchyma
Collenchyma
What is the function of sclenchyma and collenchyma?
Act as support cells that provide structure for the plant.
What is the function of parenchyma cells?
Basis of photosynthetic cells
Act as storage cells in roots
Stores starch in leaves
What are the two types of pathways water can take through the roots?
Symplastic and Apoplastic
What is the symplastic route?
It refers to water traveling straight through cells.
What is the apoplastic route?
It refers to water traveling around cells.
How to plants obtain CO2 and O2?
Through stomata in leaves and through lenticels in stems
What are CAM plants?
Plants that close their stomata and lenticels in the day and open them at night to conserve water.
What is done with CO2 collected by CAM plants?
It binds with a C3 molecule to create a C4 molecule. This is stored until the day when photosynthesis can occur.
How do most plants obtain nutrients in the soil?
Root hairs pump hydrogen ions into the soil. This displaces the positive ions in compounds found in the soil. The compounds displaced now diffuse into the roots of the plant.
What is T.A.C.T. an acronym for?
Transpiration, adhesion, cohesion, and tension
What does the T.A.C.T. model describe?
How water moves up a plant.
Define adhesion in the context of the T.A.C.T. model.
How water sticks to the surface of other materials.
Define cohesion in the context of the T.A.C.T. model.
How water sticks to itself.
What is phototropism?
Plants growing towards the light.
Who were the first people to formally document phototropism?
Charles Darwin and his son Francis Darwin (1880s)
Who discovered that a chemical was involved in phototropism?
Boysen-Jensen (1913)
Who discovered the chemical auxin?
Frits Went (1926)
What is the function of auxin?
It stimulates elongation in plant cells.
What effect does light have on auxin?
Light inhibits auxin thus inhibiting growth where light strikes a plant.
What is gravitropism?
The inhibition or stimulation of growth in a plant due to the force of gravity on it.
What are amyloplasts?
Molecules that fall in plant cells. They either inhibit or stimulate growth.
