Download Regulation of Response to Abiotic Factors

Warm-Up (2/22)
On the piece of white paper from the back, answer
the following question.
Explain how plants obtain energy from
sunlight.
Name
Date
Period
2E.2a: In plants, physiological events involve interactions between environmental
stimuli and internal molecular signals.
2E.2a.1: Phototropism, or the response to the presence of light.
2E.2a.2: Photoperiodism, or the response to change in the length of the night, that
results in flowering in long-day and short-day plants.
2E.2b: In animals, internal and external signals regulate a variety of physiological
responses that synchronize with environmental cycles and cues.
Illustrative example: Circadian rhythms
2E.2c: In fungi, protists and bacteria, internal and external signals regulate a
variety of physiological responses that synchronize with environmental cycles and
cues.
Illustrative example: Fruiting body formation in fungi, slime molds and certain types
of bacteria.
Regulation of Response: light in plants
Plants respond to light
through phototropism.
Regulation of Response: light in plants
Photoperiodism:
Plants respond to the
length of day differently.
Short-day plants flower when
the day is short; long-day plants
flower when day is long.
Regulation of Response: light in plants
Photoperiodism:
Plants respond to the
length of day differently.
Short-day plants flower when
the day is short; long-day plants
flower when day is long.
Experiment!
Critical Thinking Question #1
The protein auxin is responsible for plant cell growth.
When light shines on a plant cell, a pathway is stimulated to
degrade auxin; thus, dark cells become larger and light
cells become smaller. This results in the plant “bending”
toward the source of the light, a phenomenon also referred
to as phototropism.
Which of the following statements best justifies the claim
that auxin levels regulate phototropism? (LO 2.36)
a. A plant evenly illuminated from all sides will grow perfectly vertically.
b. Seeds lacking auxin never germinate, or sprout from the ground.
c. Artificial application of auxin to the illuminated surface of a plant
prevents phototropism.
d. Removing a transcriptional activator of the auxin gene results in
enhanced phototropism.
2E.2a: In plants, physiological events involve interactions between environmental
stimuli and internal molecular signals.
2E.2a.1: Phototropism, or the response to the presence of light.
2E.2a.2: Photoperiodism, or the response to change in the length of the night, that
results in flowering in long-day and short-day plants.
2E.2b: In animals, internal and external signals regulate a variety of physiological
responses that synchronize with environmental cycles and cues.
Illustrative example: Circadian rhythms
2E.2c: In fungi, protists and bacteria, internal and external signals regulate a
variety of physiological responses that synchronize with environmental cycles and
cues.
Illustrative example: Fruiting body formation in fungi, slime molds and certain types
of bacteria.
Regulation of Response: light in animals
Circadian rhythms
are an animal’s
internal clock.
Regulation of Response: light in animals
Circadian rhythms
are an animal’s
internal clock.
The clock runs without external
stimuli, but will be re-trained when
exposed to new stimuli.
Regulation of Response: light in animals
Circadian rhythms
are an animal’s
internal clock.
The clock runs without external
stimuli, but will be re-trained when
exposed to new stimuli.
Test subjects placed in
natural light cycles for
10 days, constant light
for 25 days, then
returned to natural
cycles for 10 days.
2E.2a: In plants, physiological events involve interactions between environmental
stimuli and internal molecular signals.
2E.2a.1: Phototropism, or the response to the presence of light.
2E.2a.2: Photoperiodism, or the response to change in the length of the night, that
results in flowering in long-day and short-day plants.
2E.2b: In animals, internal and external signals regulate a variety of physiological
responses that synchronize with environmental cycles and cues.
Illustrative example: Circadian rhythms
2E.2c: In fungi, protists and bacteria, internal and external signals regulate a
variety of physiological responses that synchronize with environmental cycles and
cues.
Illustrative example: Fruiting body formation in fungi, slime molds and certain types
of bacteria.
Regulation of Response: starvation
Fungi, bacteria
and protists
Fungi
respond to lack of
food by sending
out spores.
Spores are like asexual
seeds – durable and will
make a new generation.
Fruiting Bodies
Regulation of Response: starvation
Fungi, bacteria
and protists
Fungi
respond to lack of
food by sending
out spores.
Spores are like asexual
seeds – durable and will
make a new generation.
Fruiting Bodies
Regulation of Response: starvation
So, I asked this girl
out and she turned
me down, and I was
like, “hey come on,
I’m a fungi!”
Fungi, bacteria
and protists
respond to lack of
food by sending
out spores.
Spores are like asexual
seeds – durable and will
make a new generation.
Fungi Fruiting Bodies
Critical Thinking Question #2
Circadian rhythms are regulated by the
secretion of melatonin, a hormone, from
the pineal gland to many different cell types
in the body. Activation of the melatonin
synthesis in the pineal gland is activated by
the suprachiasmatic nucleus (SCN), a
region of the brain. Describe the role of
melatonin receptors in the regulation of
circadian rhythms. (LO 2.37)
Closure
On the piece of white paper from the
back, answer the following question:
Describe the evolutionary
advantage to fruiting body
formation.
Name
Date
Period
Scale
1 – 10