1. Animal Tissues
and Organ Systems
Chapter 32

2. Impacts, Issues
Open or Close the Stem Cell Factories?
 Only embryonic stem cells can differentiate into
any specialized cell in the body; engineered
stem cells are not yet safe for humans

3. Homeostasis in Animals
 Body parts must interact to perform many tasks
• Coordinate and control individual parts
• Acquire and distribute raw materials to cells and
dispose of wastes
• Protect tissues against injury or attack
• Reproduce, nourish and protect offspring through
early growth and development
• Maintain the internal environment (homeostasis)

4. 32.1 Organization of Animal Bodies
 Tissue
• Interacting cells and extracellular substances that
carry out one or more specialized tasks
 Organ
• Structural unit of two or more tissues organized in
a specific way to carry out specific tasks
 Organ systems
• Two or more organs and other components
interacting in a common task

5. Animal Cells are United by Cell Junctions
 Tight junctions
• Prevent fluid from seeping between epithelial
cells; fluid must pass through cells
 Adhering junctions
• Hold cells together at distinct spots
 Gap junctions
• Permit ions and small molecules to pass from
cytoplasm of one cell to another

6. 32.1 Key Concepts
Animal Organization
 All animals are multicelled, with cells joined by
cell junctions
 Typically, cells are organized in four tissue
types: epithelial tissue, connective tissue,
muscle tissue, and nervous tissue
 Organs, which consist of a combination of
tissues, interact in organ systems

7. 32.2 Epithelial Tissue
 Epithelium (epithelial tissue)
• A sheet of cells that covers the body’s outer
surface and lines its internal ducts and cavities
 Basement membrane
• A secreted extracellular matrix that attaches the
epithelium to the underlying tissue
 Microvilli
• Fingerlike projections of absorptive epithelia

8. General Structure of Simple Epithelium

9. free surface of a
simple epithelium
basement membrane
(material secreted by
epithelial cells)
underlying connective tissue
Fig. 32-3, p. 541

10. Describing Epithelial Tissues
 Thickness
• Simple epithelium: One cell thick
• Stratified epithelium: More than one cell thick
 Cell shape
• Squamous: Flattened
• Cuboidal: Cube-shaped
• Columnar: Tall

11. Types of Epithelial Tissues

12. Simple squamous epithelium
• Lines blood vessels, the
heart, and air sacs of lungs
• Allows substances to cross
by diffusion
Fig. 32-4a, p. 541

13. Fig. 32-4b, p. 541

14. Simple cuboidal epithelium
• Lines kidney tubules, ducts
of some glands, oviducts
• Functions in absorption an
secretion, movement of materials
Fig. 32-4b, p. 541

15. Fig. 32-4c, p. 541

16. Simple columnar epithelium mucus-secreting gland cell
• Lines some airways, parts
of the gut
• Functions in absorption and
secretion, protection
Fig. 32-4c, p. 541

17. Glandular Epithelium
 Glands
• Organs that release substances onto the skin, or
into a body cavity or interstitial fluid
 Exocrine glands (glands with ducts)
• Deliver secretions to an external or internal
surface (saliva, milk, earwax, digestive enzymes)
 Endocrine glands (no ducts)
• Secrete hormones which are carried in blood

18. 32.3 Connective Tissues
 Connective tissues consist of cells and the
extracellular matrix they secrete
 Connective tissues connect body parts and
provide structural and functional support to other
body tissues

19. Soft Connective Tissues
 Loose connective tissue
• Fibroblasts secrete a matrix of complex
carbohydrates with fibers dispersed widely
through the matrix
 Dense connective tissue (dense collagen fibers)
• Dense irregular: Supports skin, internal organs
• Dense regular: Ligaments and tendons

20. Specialized Connective Tissues
 Cartilage: Rubbery extracellular matrix,
supports and cushions bones
 Adipose tissue: Fat filled cells, stores energy,
cushions and protect organs
 Bone: Rigid support, muscle attachment,
protection, mineral storage, blood production

21. Connective Tissues

22. Connective Tissues

23. Fig. 32-5a, p. 542

24. Fig. 32-5b, p. 542

25. Fig. 32-5c, p. 542

26. Fig. 32-5d, p. 542

27. Fig. 32-5e, p. 543

28. Fig. 32-5f, p. 543

29. Cartilage and Bone Tissue

30. cartilage at the
end of long bone
compact bone
tissue
spongy bone
tissue
Fig. 32-6, p. 543

31. A Fluid Connective Tissue
 Blood: Plasma, blood cells and platelets

32. white
blood
cell
red
blood
cell
platelet
Fig. 32-7, p. 543

33. 32.4 Muscle Tissues
 Muscle tissue is made up of cells that contract
when stimulated, requires ATP energy

34. Three Types of Muscle Tissues
 Skeletal muscle tissue
• Moves the skeleton (voluntary)
• Long, striated cells with many nuclei
 Cardiac muscle tissue
• Heart muscle (involuntary)
• Striated cells with single nuclei
 Smooth muscle tissue
• In walls of hollow organs (involuntary)
• No striations, single nuclei

35. 32.5 Nervous Tissue
 Nervous tissue
• Consists of specialized signaling cells (neurons)
and cells that support them (neuroglial cells)
 Nervous tissue detects internal and external
stimuli, and coordinates responses to stimuli

36. Neurons
 Neurons
• Excitable cells with long cytoplasmic extensions
• Send and receive electrochemical signals
 Three types of neurons
• Sensory neurons are excited by specific stimuli
• Interneurons integrate sensory information
• Motor neurons relay commands from brain and
spinal cord to muscles and glands

37. A Motor Neuron

38. Coordination of Nervous Tissue
and Skeletal Muscle

39. 32.2-32.5 Key Concepts
Types of Animal Tissues
 Epithelial tissue covers the body’s surface and
lines its internal tubes
 Connective tissue provides support and
connects body parts
 Muscle tissue moves the body and its parts
 Nervous tissue detects internal and external
stimuli and coordinates responses

40. 32.6 Overview of Major Organ Systems
 In vertebrates, organs arise from three
embryonic germ layers
• Ectoderm (outermost layer) forms nervous tissue
and epithelium of skin
• Mesoderm (middle layer) forms muscle,
connective tissue, and lining of body cavities
• Endoderm (innermost layer) forms epithelium of
gut and lungs

41. Body Cavities and Directional Terms

42. Body Cavities and Directional Terms

43. Body Cavities and Directional Terms

44. cranial cavity
spinal cavity
thoracic cavity
diaphragm
abdominal cavity
pelvic cavity
Fig. 32-11a, p. 546

45. Dorsal Surface
transverse
midsagittal
ANTERIOR POSTERIOR
frontal
Ventral Surface
Fig. 32-11b, p. 546

46. SUPERIOR
(of two body parts, distal (farthest from
the one closer to head) trunk or from origin
of a body part)
frontal
plane midsagittal proximal (closest
plane to trunk or to
(aqua) (green)
point of origin of
a body part)
ANTERIOR
(at or near
front of
POSTERIOR
body)
(at or near
back of body)
transverse
plane
INFERIOR (yellow)
(of two body parts,
the one farthest from head) Fig. 32-11c, p. 546

47. Animation: Human body cavities

48. Animation: Directional terms and planes
of symmetry

49. Eleven Vertebrate Organ Systems

50. Eleven Vertebrate Organ Systems

51. Integumentary Nervous Muscular Skeletal Circulatory Endocrine
System System System System System System
Protects body Detects external Moves body Supports and Rapidly Hormonally
from injury, and internal and its internal protects body transports controls body
dehydration, and stimuli; controls parts; parts; provides many materials functioning;
some pathogens; and coordinates maintains muscle to and from with nervous
controls its responses to posture; attachment interstitial fluid system
temperature; stimuli; generates heat sites; produces and cells; helps integrates short-
excretes certain integrates all by increases red blood cells; stabilize and long-term
wastes; receives organ system in metabolic stores calcium, internal pH and activities. (Male
some external activities. activity. phosphorus. temperature. testes added.)
stimuli. Fig. 32-12a, p. 547

52. Lymphatic System Respiratory System Digestive System Urinary System Reproductive System
Collects and Rapidly delivers Ingests food and Maintains the Female: Produces eggs;
returns some oxygen to the water; volume and after fertilization, affords
tissue fluid to tissue fluid that mechanically, composition a protected, nutritive
the bloodstream; bathes all living chemically breaks of internal environment for the
defends the body cells; removes down food and environment; development of new
against infection carbon dioxide absorbs small excretes excess individuals. Male:
and tissue wastes of cells; molecules into fluid and Produces and transfers
damage. helps regulate internal bloodborne sperm to the female.
pH. environment; wastes. Hormones of both
eliminates food systems also influence
residues. other organ systems.
Fig. 32-12b, p. 547

53. Animation: Human organ systems

54. 32.6 Key Concepts
Organ Systems
 Vertebrate organ systems compartmentalize the
tasks of survival and reproduction for the body
as a whole
 Different systems arise from ectoderm,
mesoderm, and endoderm, the primary tissue
layers that form in the early embryo

55. 32.7 Vertebrate Skin—
Example of an Organ System
 Skin is the body’s interface with the environment
• Sensory receptors, barrier against pathogens,
internal temperature control, water conservation
 Vertebrate skin is made up of all four tissue
types arranged in two layers:
• Outer epidermis contain keratinocytes
• Deeper dermis contains nerves, blood and lymph
vessels, hair follicles and glands

56. Skin Structure

57. Skin Structure

58. Skin Structure

59. hair
epidermis
dermis
hypodermis
sensory
oil gland neuron
hair follicle sweat gland
blood vessels smooth muscle
Fig. 32-13a, p. 548

60. outer
flattened
epidermal
cells
cells
being
flattened
dividing
cells
dermis
Fig. 32-13b, p. 548

61. hair’s
cuticle
one hair cell
keratin
polypeptide
keratin chain
macrofibril
Fig. 32-13c, p. 548

62. Animation: Structure of human skin

63. Animation: Hair fine structure

64. Frog Skin
 Amphibians may have glands that secrete
mucus, distasteful chemicals, or poisons
• Pigmented cells in dermis warn predators

65. Fig. 32-14b, p. 549

66. mucous gland poison gland pigmented cell
Fig. 32-14b, p. 549

67. Sunlight and Human Skin
 Melanocytes in skin make a brown pigment
(melanin) which affects skin color and tanning
 Melanin protects against UV radiation
• A little UV promotes vitamin D production
• A lot of UV damages DNA and promotes cancer

68. 32.8 Farming Skin
 Commercially grown skin substitutes are already
in use for treatment of chronic wounds
 Skin may be a source of stem cells that could be
used to grow other organs

69. 32.7-32.8 Key Concepts
A Closer Look at Skin
 Skin is an example of an organ system
 It includes epithelial layers, connective tissue,
adipose tissue, glands, blood vessels, and
sensory receptors
 It helps protect the body, conserve water, control
temperature, excrete wastes, and detect
external stimuli

70. Animation: Altering hair structure

71. Animation: Cell junctions

72. Animation: Functional zones of a motor
neuron

73. Animation: Muscle tissues

74. Animation: Organization of animal cells

75. Animation: Soft connective tissues

76. Animation: Specialized connective
tissues

77. Animation: Structure of an epithelium

78. Animation: Types of simple epithelium

79. ABC video: A Saving Graft

80. ABC video: New Hands

81. Video: Stem Cells