Transcript Lecture #18 Date

AP Biology
3/8/13
Chp.40:
An Introduction to
Animal Structure
and Function
Diverse Forms, Common Challenges
LE 40-3
Mouth
Diffusion
Gastrovascular
cavity
Diffusion
Diffusion
 All organisms
need to perform
certain functions:
1. Gas exchange
with
environment
2. Obtain and digest
food
3. Eliminate Waste
Single cell
Two cell layers
Structure and Function….
 Similar structures
have evolved
multiple times to
deal with similar
functions
 Ex: Convergent
evolution in
swimming animals
….Anatomy and Physiology
LE 40-4
 Anatomy: structure
 Physiology: function
Respiratory
system
0.5 cm
Heart
Nutrients
Digestive
system
50 µm
External environment
CO2 O
Food
2
Mouth
Animal
body
A microscopic view of the lung reveals
that it is much more spongelike than
balloonlike. This construction provides
an expansive wet surface for gas
exchange with the environment (SEM).
Cells
Circulatory
system
10 µm
Interstitial
fluid
Excretory
system
The lining of the small intestine, a digestive
organ, is elaborated with fingerlike projections
that expand the surface area for nutrient
absorption (cross-section, SEM).
Anus
Unabsorbed
matter (feces)
Metabolic waste
products (urine)
Inside a kidney is a mass of microscopic
tubules that exchange chemicals with
blood flowing through a web of tiny
vessels called capillaries (SEM).
Animal Anatomy and Physiology
 Most animals are composed
of specialized cells organized
into tissues that have
different functions
 Tissues make up organs,
which together make up
organ systems
 Different tissues have
different structures that are
suited to their functions
 Tissues are classified into
four main categories:
epithelial, connective,
muscle, and nervous
Organ systems
 Organ: organization of





tissues
Mesentaries: suspension of
organs (connective tissue)
Thoracic cavity (lungs and
heart)
Abdominal cavity
(intestines)
Diaphragm (respiration)
Organ systems…...
 (See Table 40.1)











Digestive-food processing
Circulatory-internal distribution
Respiratory-gas exchange
Immune/Lymphatic-defense
Excretory-waste disposal;
osmoregulation
Endocrine-coordination of body
activities
Reproductive-reproduction
Nervous-detection of stimuli
Integumentary-protection
Skeletal-support; protection
Muscular-movement; locomotion
Bioenergetics
 the flow of energy
through an animal,
limits behavior,
growth, and
reproduction
Internal regulation
 Interstitial fluid: internal
fluid environment of
vertebrates; exchanges
nutrients and wastes
 Homeostasis:
“steady state” or
internal balance
Regulation
 Negative feedback:
change in a physiological
variable that is being
monitored triggers a
response that counteracts
the initial fluctuation; i.e.,
body temperature
 Positive feedback:
physiological control
mechanism in which a
change in some variable
triggers mechanisms that
amplify the change; i.e.,
uterine contractions at
childbirth
Homeostatic
Regulation of
cellular fluid
Metabolism: sum of all energyrequiring biochemical reactions
 Catabolic processes of
cellular respiration
(breaking down)
 Calorie; kilocalorie/C
 Basal Metabolic Rate
(BMR): minimal rate
powering basic functions of
life (endotherms)
 Standard Metabolic Rate
(SMR): minimal rate
powering basic functions of
life (ectotherms)
This photograph shows a ghost crab in a
respirometer. Temperature is held constant
in the chamber, with air of known O2
concentration flowing through. The crab’s
metabolic rate is calculated from the
difference between the amount of O2
entering and the amount of O2 leaving the
respirometer. This crab is on a treadmill,
running at a constant speed as measurements
are made.
Similarly, the metabolic rate of
a man fitted with a breathing
apparatus is being monitored
while he exercises on a
stationary bike.
 Endotherms: bodies warmed by metabolic heat
 Ectotherms: bodies warmed by environment
Examples: (In general)
1. Endotherms –
1. Birds, mammals
2. Ectotherms –
1. Fish, reptiles,
amphibians
Vs.
• Homeotherm –
constant body temp
• Poikilotherm –
variable body temp
Endotherms
800,000
Ectotherm
Reproduction
Basal
(standard)
metabolism
Temperature
regulation
Growth
Activity
340,000
8,000
4,000
60-kg female human
from temperate climate
4-kg male Adélie penguin
from Antarctica (brooding)
0.025-kg female deer mouse
from temperate
North America
4-kg female python
from Australia
Total annual energy expenditures. The slices of the pie charts indicate energy
expenditures for various functions.
438
Human
233
Python
Deer mouse
Adélie penguin
36.5
Energy expenditures per unit mass (kcal/kg•day). Comparing the daily energy expenditures per kg of body
weight for the four animals reinforces two important concepts of bioenergetics. First, a small animal, such as
a mouse, has a much greater energy demand per kg than does a large animal of the same taxonomic class,
such as a human (both mammals). Second, note again that an ectotherm, such as a python, requires much
less energy per kg than does an endotherm of equivalent size, such as a penguin.
5.5
Homework  due Monday
 Chp.40 Guided Reading: Animal
Structure & Function
Did not use…
Tissues: groups of cells with a common
structure and function (4 types)
 1- Epithelial:
outside of
body and
lines organs
and cavities;
held
together by
tight
junctions
Tight Junctions – impermeable to water
Epithelial Tissues
 basement membrane: dense
mat of extracellular matrix
 mucous membrane
1. Simple: single layer of
cells
2. Stratified: multiple tiers of
cells
a) Cuboidal (like dice)
b) Columnar (like bricks on
end)
c) Squamous (like floor tiles)
Connective Tissues
 Bind and support other tissues
 Scattered cells through matrix
 Matrix - non-living material for the nourishment of
cells
 Fibers. Not all types of connective tissues are fibrous
though. Examples are adipose tissue and blood.
Adipose tissue gives "mechanical cushion" to our
body. The matrix of blood is plasma.
Connective
Tissues
1.
2.
3.
4.
5.
Loose connective tissue:
binds epithelia to underlying
tissue; holds organs
Fibrous connective tissue:
parallel bundles of cells
Cartilage: collagen in a
rubbery matrix
(chondroitin); flexible
support
Bone: mineralized tissue by
osteoblasts
Blood: liquid plasma matrix;
erythrocytes (RBC’s) carry
O2; leukocytes (WBC’s)
immunity
Nervous Tissue
 Senses stimuli and
transmits signals from 1 part
of the animal to another
 Neuron: functional unit that
transmits impulses
 Dendrites: transmit
impulses from tips to rest of
neuron
 Axons: transmit impulses
toward another neuron or
effector
Muscle Tissues
 4- Muscle: capable of
contracting when stimulated by
nerve impulses; myofibrils
composed of proteins actin and
myosin; 3 types:
 A- Skeletal: voluntary movement
(striated)
 B- Cardiac: contractile wall of
heart (branched striated)
 C- Smooth: involuntary activities
(no striations)
Organs – Containing
multiple tissues
Lumen of
stomach
Mucosa: an epithelial
layer that lines the
lumen
Submucosa: a matrix of
connective tissue that
contains blood vessels
and nerves
Muscularis: consists
mainly of smooth muscle
tissue
0.2 mm
Serosa: a thin layer of
connective and epithelial
tissue external to the muscularis