Exam 2 review Flashcards
Plant senses
- collect information
- want to increase survival so adapt
Three steps process of plants determining environmental cues
1) sensory cells get signal and modify it
2) send signal to target cell
3) target cells receive info and respond
Signal receptor proteins
- phototropins
- phytochromes
Signal hormones
- auxin
- florigen
- expansin
Signal transduction
- convert from one form to another
- signal from outside must bind with phytochrome and be converted into a form the pant can use
- not needed if signal is already inside
Phototropism
plant bending to light
Process of phototropism
- expansin breaks cell wall
- auxin builds up of shaded side and swell
Phototropism receptors
phototropins
Wavelength that cause phototropism
blue light
Hormones in phototropism
auxin and expansin
Pigment involved in R/FR
phytochrome
Photoperiodism
length of days and the type of light the plant was last exposed to
Wave lengths of photoperiodism
red and far-red
Hormone of photoperiodism
florigen
Gravitropism
tells what direction to send the roots/shoots
Location of cells responsible for gravitropism
root tip
Type of cell for gravitropism
amyloplasts
Amyloplasts
move based on what way gravity is pulling them, increase in concentration = increased auxin
Hormone for gravitropism
auxin
Wind/touch response
mechanical, respond to environment to increase survival
Thigmotropism
slow, directional movement, trindles, use to climb
Thigmonastic movement
rapid, non-directional, electrical signals/aps that move through plants
Plant growth
continuous but not constant, based on nutrients
Aprical dominance
apical meristem will be main growth unless cut off then axillary bids will redirect growth to be full and thick
Hormone for apical dominace
auxin
Additional growth hormones
- cytokinins
- gibberillins
- ABA
- Ethylene
Cytokinins
cell growth
Gibberillins
stimulate plant growth
ABA
inhibit plant growth
Ethylene
related to plant aging, causes ripening, senescence, and abscission
Senescence
one part of plant dies
Abscission
auxin stops flowing and ethylene builds up, turn yellow and fall
Fruit ripening
starch converted into sugar by ethylene, softer, sweeter, more attractive
Physical defence
thorns, spin, cuticle
Chemical defence
toxins, hormones, secondary metabolic
Inducible defenses
intentional or caused response to protect itself
Ways that pathogens attack plants
- kill host cell and feed of cell debris
- feed on host nutrients
Hypersensitive responses
localized, immediate
- stomata close -> produce toxins -> reinforce neighbor cells -> apoptosis
Systemic Acquired Resistance
whole plant, after hypersensitive, creates resistance, primes cells in roots and shoots, expression of pathogen genes to limit the chance of infection again
Direct defense
plants directly doing defense (secreting oil)
Indirect defense
plants produce chemical that attracts predator that eats the parasite (parasitoid)
Anatomy
physical structure
Physiology
how physical structure functions
Adaptations
variation
adaptation
competition
selection
Trade-offs for adaptation
energy is put into one factor which can cause both factors to suffer
Adaptation
long-term, genetic
Acclimatization
short-term, reversible, based on environmental factors
Major tissue types
- muscular
- connective
- nervous
- epithelial
Types of Connective tissue
- loose
- dense
- supporting
- fluid
Loose CT
- packing material for organs
- allows expanding
- fibrous proteins
- has fibroblasts
Dense CT
- tightly packed
- bones and muscles
- connect tendons and ligaments
- have fibroblasts
Supporting CT
- bones and cartilage
- support and protect vertebrate
- make skeletal system
Fluid CT
- blood
- cells surrounded by extra cellular matrix to keep shape