Download Chapter 16: Tissues, Organs, and Organ Systems

Chapter 16
Tissues, Organs, and Organ Systems
Organ Donation
Copyright © 2010 Pearson Education, Inc.
16.1 Tissues
Tissues = group of similar cell types that
perform a common function.
Four basic types of tissue:
1.
2.
3.
4.
Epithelial
Connective
Muscle
Nervous
Copyright © 2010 Pearson Education, Inc.
16.1 Tissues - Epithelial Tissue
Epithelium is tightly
packed sheets of
cells
 cover organs and
outer surfaces
 line insides of
hollow organs,
vessels, and body
cavities.
Copyright © 2010 Pearson Education, Inc.
(a) Examples of organs lined with epithelial
(b) Epithelial cells in skin
tissue:
Heart and blood vessels
Epidermis
Respiratory tract
Digestive tract
Urogenital tract
(c) Epithelial cells lining
the small intestine
Figure 16.1
16.1 Tissues - Epithelial Tissue
Epithelia are polar
 anchored on one surface, but free on another
 The free side is typically exposed to the
environment or body fluids
 Can be single layer or many
layers thick
 Function in protection,
secretion, and absorption
 Epithelial cells are
continuously sloughing off and
are replaced by cell division
Copyright © 2010 Pearson Education, Inc.
16.1 Tissues - Connective Tissue
Connective Tissue
 Loosely organized and composed of cells
embedded in a matrix
 Cells
 Blood cells, adipocytes, fibroblasts,
chondrocytes, osteocytes
 Matrix is composed of two things
1. Ground substance
 Liquid, gel-like, rubbery or solid
2. Fibers
 Collagen, elastin, reticular fibers
Copyright © 2010 Pearson Education, Inc.
16.1 Tissues - Connective Tissue
Connective Tissue
 Usually binds organs or tissues to one another
 Six different types:






Loose connective tissue
Adipose tissue
Blood
Fibrous connective tissue
Cartilage
Bone
Copyright © 2010 Pearson Education, Inc.
16.1 Tissues - Connective Tissue
Loose Connective Tissue
 Most widespread tissue in
animal body
 Matrix composed of
collagen and elastin
fibers
 It is called “loose” because
fibers are loosely woven
together
 Binds epithelia to tissues,
pads skin, and holds
organs in place
Copyright © 2010 Pearson Education, Inc.
Figure 16.2a
16.1 Tissues - Connective Tissue
Adipose Tissue
 AKA Fat
 Primarily adipose cells;
small amount of matrix
 Functions
 Used for storage of
energy (fat)
 Insulation
 Padding for organs
Copyright © 2010 Pearson Education, Inc.
Figure 16.2b
16.1 Tissues - Connective Tissue
Blood
 Cellular component
 red blood cells, white
blood cells and
platelets
 Matrix is the plasma
 Functions include
carrying oxygen and
nutrients; fighting
infection
Copyright © 2010 Pearson Education, Inc.
(c) Blood
Platelet
Red
blood cell
Plasma
White
blood cell
Figure 16.2c
16.1 Tissues - Connective Tissue
Fibrous Connective
Tissue
 Forms tendons and
ligaments
 Matrix is collagen
fibers running in
parallel
Copyright © 2010 Pearson Education, Inc.
(d) Fibrous connective tissue (tendon)
Fibroblast
cell
Parallel
collagen
fibers
Figure 16.2d
16.1 Tissues - Connective Tissue
Cartilage
(e) Cartilage
(at the end of a bone)
 Chondrocytes
 Secrete rubbery matrix,
collagen and elastin
 Cartilage cushions joints,
forms support for ears
and nose
 Not vascularized, so takes
a long time to heal if
Chondrocytes
Matrix
injured
Copyright © 2010 Pearson Education, Inc.
Figure 16.2e
16.1 Tissues - Connective Tissue
Bone
 Rigid connective tissue
 Osteocytes
 secrete matrix of
collagen fibers and
calcium salts
 Bone marrow produces
blood cells
 Body can make use of
calcium from bones if
dietary levels are too low
Copyright © 2010 Pearson Education, Inc.
(f) Bone
Central
canal
Matrix
Osteocytes
Figure 16.2f
16.1 Tissues - Muscle Tissue
Muscle is contractile tissue
 Long, thin cylindrical cells called muscle
fibers
 Two proteins – actin and myosin –
interact to cause contraction of muscle
fibers
 Three types of muscle:
1. Skeletal
2. Cardiac
3. Smooth
Copyright © 2010 Pearson Education, Inc.
16.1 Tissues - Muscle Tissue
Skeletal Muscle




Usually attached to bone
Produces all voluntary movements
Striated
Long, thin, cylindrical shape
(a) Skeletal muscle (biceps)
Muscle fiber Nucleus
Copyright © 2010 Pearson Education, Inc.
Figure 16.3a
16.1 Tissues - Muscle Tissue
Cardiac Muscle
 Only found in
heart tissue
 Striated
 involuntary,
undergoes
rhythmic
contractions to produce heartbeat
 Branched, interlocking cells propagate signal
to contract almost simultaneously
(b) Cardiac muscle (heart)
Muscle fiber
Copyright © 2010 Pearson Education, Inc.
Nucleus
Figure 16.3b
16.1 Tissues - Muscle Tissue
Smooth Muscle
 Not striated
 Spindle-shaped cells
 Musculature of
organs, blood
vessels, digestive
tract
 Involuntary
 Contracts more slowly and for longer than
skeletal muscle
(c) Smooth muscle (intestine)
Muscle fiber
Copyright © 2010 Pearson Education, Inc.
Nucleus
Figure 16.3c
16.1 Tissues - Nervous Tissue
Nervous Tissue
 Neurons conduct electrical signals
 Primary cells of the brain and spinal cord
 Main function of neurons is to:
 Sense stimuli
 Process stimuli
 Transmit signals
 Most cells of nervous system do not
undergo cell division
Copyright © 2010 Pearson Education, Inc.
16.1 Tissues - Tissue Donation
Brain death and Tissue Donation
 Injuries from motor vehicle accidents, burst
blood vessels, and drowning are common
causes of brain death
 Once dead, brain cells cannot recover
 Tissues can be harvested to help others
 > One person’s tissues can improve the
lives of as many as 50 people.
Copyright © 2010 Pearson Education, Inc.
16.2
Organs and Organ Systems
 Organs are
composed of two or
more tissue types
 Organs that act
together form an
organ system
 All the organ systems
of a body form an
organism
Copyright © 2010 Pearson Education, Inc.
Muscle cell
Muscle tissue
Heart organ
Circulatory system
Organism
Figure 16.5
16.2 Organs and Organ Systems
12 Organ Systems
Copyright © 2010 Pearson Education, Inc.
Figure 16.8
16.2 Organs and Organ Systems –
The Liver as a Model Organ
 The liver sits below the
diaphragm
 comprised of four
lobes
 associated with the
gall bladder.
Copyright © 2010 Pearson Education, Inc.
Figure 16.6
16.2 Organs and Organ Systems
The Liver as a Model Organ
 The liver is an important component of the
digestive and the circulatory system
 As part of the circulatory system, the liver:
 Synthesizes blood clotting factors
 Detoxifies
 Regulates blood volume
 Destroys old red blood cells
 As part of the digestive system, the liver:
 Produces bile
 Metabolizes and stores nutrients
Copyright © 2010 Pearson Education, Inc.
16.2 Organs and Organ Systems
Liver Structure
 Epithelia
 Hepatocytes
 Lining blood vessels
 Lining bile ducts
 Connective Tissue
 Loose connective
tissue
 Kupffer cells
Copyright © 2010 Pearson Education, Inc.
16.2 Organs and Organ Systems - The Liver
as a Model Organ
 Liver transplants can be made from living
donors or from brain dead ones
 Unlike many organs, liver can regenerate
itself
 Portion can be taken from living donor and
implanted in patient
 Liver in donor and patient will regrow to
normal size
Copyright © 2010 Pearson Education, Inc.
16.2 Organs and Organ Systems
The Digestive System
Mouth
• Teeth reduce the size of
food, increasing surface
area available for digestion
by enzymes.
• Amylase enzymes in
saliva start breaking down
carbohydrates.
Copyright © 2010 Pearson Education, Inc.
Figure 16.8
16.2 Organs and Organ Systems
The Digestive System
Esophagus
• The esophagus
transports food to stomach
by rhythmic waves of
muscle contractions called
peristalsis.
Copyright © 2010 Pearson Education, Inc.
Figure 16.8
16.2 Organs and Organ Systems
The Digestive System
Stomach
• HCl starts breaking
down foods.
• The enzyme pepsin
breaks down proteins.
• Mucous prevents
gastric juices from
digesting stomach.
• Pyloric sphincter
regulates movement of
food from stomach to
small intestine.
Copyright © 2010 Pearson Education, Inc.
Figure 16.8
16.2 Organs and Organ Systems
The Digestive System
Small intestine
• Most digestion of
carbohydrates, proteins,
and fats occurs here.
• Nutrients are absorbed
into the bloodstream.
Large intestine
• Water is reabsorbed
Copyright © 2010 Pearson Education, Inc.
Figure 16.8
16.2 Organs and Organ Systems - The
Digestive System
 Villi and microvilli increase the surface
area of the intestines to allow nutrient
absorption
One villus
Small intestine
Micrograph
Villus
Lumen
Blood
capillaries
Mucosal folds
Microvilli
Nutrients in small intestine
Venule
Arteriole
Lymphatic
vessel
Copyright © 2010 Pearson Education, Inc.
Figure 16.9
16.2 Organs and Organ Systems
The Digestive System
Accessory Organs
Liver
• Produces bile which
aids absorption of fats
Gall bladder
• Stores bile and
empties into small
intestine
Copyright © 2010 Pearson Education, Inc.
Figure 16.8
16.2 Organs and Organ Systems
The Digestive System
Accessory Organs
Pancreas
• Produces LOTS of
digestive enzymes
• Produces a buffer
that neutralizes stomach
acid
• Enzymes & buffer are
released into small
intestine
Copyright © 2010 Pearson Education, Inc.
Figure 16.8
16.2 Organs and Organ Systems
An organ system consists of many
organs working together
 Failure of one organ may compromise the
entire system
 Intestine transplants and pancreatic
transplants are becoming more common
 Gall bladder and stomach transplants are
rarely done
 Organ failure can also disrupt multiple
systems
Copyright © 2010 Pearson Education, Inc.
16.2 Organs and Organ Systems
PLAY
Animation—The Digestive System
Copyright © 2010 Pearson Education, Inc.
16.2 Organs and Organ Systems
Evolution of the Digestive System
 Paramecia use digestive food vacuoles
 Hydra have an extracellular digestive sac
 Earthworms have alimentary canal
 Allows for ‘assembly line’ like specialization
Copyright © 2010 Pearson Education, Inc.
Figure 16.9
Homeostasis
Homeostasis
 a dynamic state of equilibrium in which
internal conditions remain relative stable
(Steady State)
 homeostasis regulates conditions in the
internal environment
 A homeostatic control system has




a receptor
a control center
a set point
an effector
Copyright © 2010 Pearson Education, Inc.
LE 40-11
Response
No heat
produced
Heater
turned
off
Room
temperature
decreases
Set
point
Too
hot
Set point
Control center:
thermostat
Too
cold
Room
temperature
increases
Set
point
Heater
turned
on
Response
PowerPoint lecture prepared by
Heat
James M. Hutcheon
produced
Georgia Southern University
Copyright © 2010 Pearson Education, Inc.
16.3 Regulating the Internal Environment
Homeostasis
 Negative feedback is when the outcome
of a process inhibits that process.
(a) If blood glucose
level rises...
Liver converts glucose
to glycogen.
Pancreas
secretes insulin.
(b) If blood glucose
level falls...
Glucose
Glycogen
Liver
Blood glucose
level falls.
Homeostasis
Normal blood glucose level
Glucose levels rise.
Glucose
Glycogen
Pancreas secretes glucagon.
Liver
Liver breaks down glycogen
into glucose and releases
glucose into bloodstream.
Copyright © 2010 Pearson Education, Inc.
Figure 16.11
16.3 Regulating the Internal Environment
Homeostasis
 Positive feedback occurs when the outcome of
a process increases or intensifies that process.
 During childbirth, hormones cause muscles of
uterus to contract
 Uterine contractions cause even more hormones
to be released, which intensify the contractions
 > In animals, regulation is usually by negative
feedback because positive feedback often
results in amplification – away from homeostasis
Copyright © 2010 Pearson Education, Inc.
16.3 Regulating the Internal Environment –
Organ Donation
 The best candidates to donate organs are
those who have died of brain injury.
 In cardiac death, organs deteriorate due to
lack of oxygen, and thus are less suitable for
transplant.
 Thousands of lives are saved each year
through organ donation.
 The decision to become a donor now can
save families from making difficult
decisions later.
Copyright © 2010 Pearson Education, Inc.