Plant Biology Lecture Notes

These flashcards cover key concepts related to plant biology as discussed in the lecture notes.

What photosynthetic structures are found in whisk ferns?

Photosynthesis occurs in branches and stems, as they do not have leaves.

What is a rhizome?

An underground stem that gives rise to aerial stems and roots.

Where are sporangia located in ferns?

Sporangia are found on the bottom of the leaves.

What do spores give rise to in the fern life cycle?

Spores give rise to the gametophyte generation.

What process produces two nuclei from one?

Mitosis produces two nuclei from one.

What is meiosis used for in plants?

Meiosis is needed to go from diploid to haploid.

What is the dominant generation in pine trees?

The sporophyte is the dominant generation in pine trees.

Why is the evolution of pollen important for plants?

Pollen allows fertilization without the need for water, enabling plants to thrive in drier environments.

What is the function of wood in plants?

Wood provides structural support, allowing plants to grow big and strong.

How do Ginkgophyta spread pollen?

Pollen spreads through the wind; male plants are more commonly planted, while female plants emit a foul odor.

What does a pollen cone produce?

A pollen cone produces microspores.

What is the role of meiosis in spore production?

Meiosis produces four nuclei, keeping one to develop into a spore.

What does the ovule do?

The ovule is protected by diploid tissue.

What is a dependent gametophyte?

A plant life stage where the haploid gametophyte generation is smaller and nutritionally reliant on the sporophyte.

What is the function of sepals in flowers?

Sepals protect the petals from being chewed on and shield them from cold weather.

What do you call plants that have both male and female reproductive organs?

Dioecious plants are those that are both male and female.

What do bees see that helps them pollinate?

Bees can see ultraviolet light.

What are the three methods of seed dispersal?

Wind, animal, and water are methods of dispersal.

What are terpenoids and their functions?

Terpenoids are lipids that produce odor, repel herbivores, and include spices.

What do antioxidants do for plants?

Antioxidants provide electrons for free radicals.

What role does chlorophyll play in leaves during fall?

Chlorophyll masks the leaves' color until it breaks down in fall.

What is the relationship between male and female structures in plants?

Males produce pollen grains; females produce ovules.

What does it mean when a sporophyte is described as dominant?

The sporophyte is larger and lives longer than the gametophyte generation.

What is a photoreceptor?

A photoreceptor is a protein that absorbs light and triggers biological responses in plants.

What is xylem made of?

Xylem is made of cellulose.

How does closing stomata affect plants?

Closing stomata interferes with gas exchange.

What does phloem loading involve?

Phloem loading involves the transport of sugars.

What influences plant growth in response to day and night?

Receptors tell plants when it’s night or day.

What does morphology refer to in flowers?

Morphology refers to characteristics like bigger petals and more color.

What is the ploidy of the mother cell before meiosis?

The mother cell is diploid before going through meiosis.

What is a key characteristic of bryophytes?

Bryophytes are non-vascular plants, often needing moist conditions.

What is the role of the sieve plate in phloem?

The sieve plate helps with clogging during sugar transport.

What are flowers, fruit, and roots considered in terms of nutrients?

They are all sugar sinks.

root apical meristem (ram)

a region of actively dividing cells located at the tip of a root, responsible for primary growth, producing new cells that differentiate into various root tissues, and enabling the root to penetrate the soil

epidermis

outermost layer of skin

cuticle

outer covering; provides protection and regulates water loss

node

a point on a plant stem where a leaf or leaves are attached

internode

the region or segment of a stem located between 2 successive nodes ( leaves or branch attach)

axillary meristem

a group of undifferentiated cells located in the leaf axil

blade

the flat, expanded part of a leaf

petiole

the stalk that connects a leaf to the stem of a plant

simple leaf

single, undivided

compound leaf

divided blade into multiple leaflets

woody plants

a plant that produces wood as its a structural tissue

root cap

a protective layer of cells; covers the tip of the root

passive transport

membrane transport; no energy; down concentration gradient

passive diffusion

membrane transport; no energy, down concentration gradient

facilitated diffusion

passive transport, down concentration, no energy, needs channels or proteins

channels

channel proteins or carrier proteins

transporters

transmembrane proteins that facilitate the movement of ions across the membrane

aqauporins

transmembrane proteins that act as a water channel

symplast

connected by plasmodesmata, inner part of the plant, bounded by plasma membrane

plasmodesmata

small channels that directly connect the cytoplasm of neighboring plant cells to each other

apoplast

the space outside the plasma membrane that allows free movement of material

bulk flow

heavy amount of water to travel through xylem

cohesion- tension theory

explains how water, despite gravity moves upward through plants

surface tension

the property of the surface of a liquid that allows it to resist an external force, due to the nature of its molecule

sieve plates

the connection site between sieve elements

p protein

structural proteins found in the sieve elements of phloem tissue

sugar source

a plant organ that produces or releases more sugar than it consumes

phototropism

the directional growth or movement of a plant or part of a plant toward or away from a light source

tropism

directional growth responses to the directional stimuli

auxins

plant hormones that play a crucial role in regulating plant growth and development

cell elongation

involves irreversible cell expansion facilitated by cell wall loosening and water uptake, often regulated by hormones like auxin

photoreceptor

a protein that absorbs photons of light

cryptochromes

regulate various biological process; circadian rhythms

phototropin

mediate for phototropism, chloroplast movement, leaf expansion, stomatal opening

resistance genes

genes that enable organisms, to detect and respond to pathogen attacks

avirulence genes

gene-for-gene relationship with their host plant

hypersensitive response

a localized induced cells defense in a host plant at the site of pathogen infection

pathogen

bacterium, virus, disease