BILD 2 Biology
description
Transcript of BILD 2 Biology
Basic Principles of Animal Form and Function
Chapter 40
Questions prepared by
Christopher Gregg Louisiana State University
John Lepri University of North Carolina, Greensboro
classes.biology.ucsd.edu/bild2.FA14/!Everest: 8,848 m (29,029 ft) above sea level
Bar-Headed Goose Migration
Himalayas!
Evolutionary Adaptation
Everest for Homo sapiens !
Questions prepared by
Christopher Gregg Louisiana State University
John Lepri University of North Carolina, Greensboro
How do we study Biology?!
Basic Principles of Animal Form and Function
Questions prepared by
Christopher Gregg Louisiana State University
John Lepri University of North Carolina, Greensboro
Biology is not!!a vocabulary and knowledge base!
(although you need these to study biology)!
Biology is !!a set of concepts and a way of asking and
answering questions!
The Best Way to Learn Biology is by Asking and Answering Biological Questions"• Ways to do that in this course:"
– Before lecture: Reading; Reading quizzes* "– At lecture: Note taking; clicker questions "– After lecture: Reading, Concept Checks; Tutorials*"– Section: Working sample problems; Discussion"– Study groups: Group problem solving"– Office hours: Discussion and problem solving"
Basic Principles of Animal Form and Function
Chapter 40
Questions prepared by
Christopher Gregg Louisiana State University
John Lepri University of North Carolina, Greensboro
Homeostasis!
Figure 32.3
River otter (temperature regulator)
40
Largemouth bass (temperature conformer)
Ambient (environmental) temperature (°C)
30
20
10
0 0 40 30 20 10
Bod
y te
mpe
ratu
re (°
C)
What hypothesis best fits these data?"A) Maia, the spider crab, is an
osmoconformer in salt water but is capable of osmoregulation in fresh water."
B) Nereis, the clam worm, is an osmoconformer in fresh water and is capable of osmoregulation in brackish water."
C) Carcinus, the shore crab, is capable of osmoregulation in brackish water and fresh water."
D) All three crabs are osmoregulators in all three environments."
Osmolarity:!Moles of solute per liter of solution (e.g. body fluid)!
Figure 32.8 Sensor/control center: Thermostat in hypothalamus
Stimulus: Decreased body
temperature
Body temperature increases.
Body temperature decreases.
Homeostasis: Internal body
temperature of approximately
36–38°C
Response: Blood vessels in skin dilate.
Response: Shivering
Sensor/control center: Thermostat in hypothalamus
Response: Blood vessels in skin constrict.
Stimulus: Increased body
temperature
Response: Sweat
Figure 32.4
Sensor/ control center: Thermostat turns heater off.
Sensor/ control center: Thermostat turns heater on.
Stimulus: Room
temperature increases.
Stimulus: Room
temperature decreases.
Room temperature increases.
Room temperature decreases.
Set point: Room temperature
at 20°C
Response: Heating stops.
Response: Heating starts.
Figure 32.UN02
Stimulus: Change in internal variable
Homeostasis
Response/effector
Control center
Sensor/receptor
Figure 32.8a
Sensor/control center: Thermostat in hypothalamus
Body temperature decreases.
Homeostasis: Internal body
temperature of approximately
36–38°C
Response: Blood vessels in skin dilate.
Stimulus: Increased body
temperature
Response: Sweat Which of the following is an example of a negative feedback response?"
A. As the uterus contracts in labor and delivery, more of the hormone oxytocin is released to intensify uterine contractions. "
B. Meerkats bask in the sun in the cool mornings but avoid the sun during the heat of the day. "
C. Sexual stimulation leads to sexual arousal."D. A nursing baby stimulates the release of oxytocin,
which causes letdown of milk."
Basic Principles of Animal Form and Function
Chapter 40
Questions prepared by
Christopher Gregg Louisiana State University
John Lepri University of North Carolina, Greensboro
Endothermy and
Ectothermy!
Figure 32.5
(a) A walrus, an endotherm
(b) A lizard, an ectotherm
Figure 32.6 Radiation
Convection
Evaporation
Conduction
Figure 32.8 Sensor/control center: Thermostat in hypothalamus
Stimulus: Decreased body
temperature
Body temperature increases.
Body temperature decreases.
Homeostasis: Internal body
temperature of approximately
36–38°C
Response: Blood vessels in skin dilate.
Response: Shivering
Sensor/control center: Thermostat in hypothalamus
Response: Blood vessels in skin constrict.
Stimulus: Increased body
temperature
Response: Sweat
Basic Principles of Animal Form and Function
Chapter 40
Questions prepared by
Christopher Gregg Louisiana State University
John Lepri University of North Carolina, Greensboro
Countercurrent heat exchange!
Figure 32.7
Canada goose
Blood flow
Artery Vein
Heat transfer
Cool blood Warm blood
Key
30°
35°C
9°
20°
10°
18°
27°
33°
2
3 1