Transcript Photosynthesis

Chapter 33
Animal Organization
& Homeostasis
Types of Epithelial Tissues
Animal Organization
& Homeostasis
in the Vertebrates
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Outline
Tissue Types
Epithelial
Connective
Muscular
Nervous
Organs
Organ Systems
Homeostasis
Negative Feedback
Positive Feedback
Animal Organization
& Homeostasis
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Levels of Organization
Animal Organization
& Homeostasis
Tissue - Group of similar cells performing a
similar function
Organ - Group of tissues performing a
specialized function
Organ System - Collection of several organs
functioning together
Organism - A collection of organ systems
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Types of Tissues
Animal Organization
& Homeostasis
Four major vertebrate tissue types
Epithelial
Connective
Muscular
Nervous
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Types of Epithelial Tissues
Animal Organization
& Homeostasis
in the Vertebrates
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Epithelial Tissue
Animal Organization
& Homeostasis
Epithelial tissue:
Forms a continuous layer over body surfaces
Lines inner cavities
Forms glands
- Exocrine glands - Secrete products into ducts or
cavities
- Endocrine glands - Secrete products directly into
the bloodstream
Covers abdominal organs
Three types of epithelial tissues:
Squamous – Flat cells
Cuboidal - Cube-shaped cells
Columnar – Pillar-shaped cells
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Connective Tissue
Animal Organization
& Homeostasis
Connective tissues consist of:
Fibroblast cells
A matrix containing collagen and elastic fibers
Loose fibrous connective tissue
Allows organs to expand
Dense fibrous connective tissue
Strong connective tissue
- Tendons
- Ligaments
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Animal Tissue
Organization
Diagram of Fibrous Connective
& Homeostasis
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Connective Tissue
Animal Organization
& Homeostasis
Adipose Tissue
Insulates the body and provides padding
Cartilage
Classified according to type of collagen and
elastic fibers found in the matrix
Cartilage cells (chondrocytes), lie in small
chambers (lacunae) in the matrix
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Animal Organization
& Homeostasis
Connective Tissue Examples
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Connective Tissue
Animal Organization
& Homeostasis
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Compact Bone
Matrix is inorganic salts deposited around protein
fibers
Bone cells (osteocytes) are located in lacunae
Lacunae arranged in concentric circles within
osteons around tiny tubes (central canals)
Blood
Animal Organization
& Homeostasis
Actually a connective tissue in which cells are
embedded in a liquid matrix (plasma)
Red blood cells - erythrocytes
White blood cells - leukocytes
Transports nutrients and oxygen to cells
Removes carbon dioxide and other wastes
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Animal Organization
& Homeostasis
Blood, a Liquid Tissue
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Muscular Tissue
Animal Organization
& Homeostasis
Contractile cells containing actin and myosin
filaments
Cells are called muscle fibers
Skeletal Muscle
- Voluntary - Long, striated fibers
Smooth Muscle
- Involuntary - No striations
Cardiac Muscle
- Striated, but mostly involuntary
- Bound by intercalated disks
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Animal Organization
& Homeostasis
Muscular Tissue
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Nervous Tissue
Animal Organization
& Homeostasis
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Nervous Tissue: neurons-specialized for the transmission of nerve
impulses.
 Made up of dendrites, a cell body, and an axon
 Dendrites (like antennae) receive signals from sensory receptors.
 Cell body contains the nucleus and organelles.
 Axons conduct a nerve impulse away from the cell body.
- Myelin-white matter
- Unmyelinated fibers, cell bodies, and dendrites-grey matter
- A nerve is a bundle of axons bound together by connective tissue.
 Neuroglia support and nourish neurons
Neurons
Animal Organization
& Homeostasis
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Nervous Tissue
Animal Organization
& Homeostasis
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Nervous system regulates body response to stimuli and
has three main functions
Sensory input
- Sensory (afferent) carrying impulses from the body to the
CNS
- Transmit info to the spinal cord
Data integration
- Spinal cord and brain integrate
- Decision is made regarding appropriate response
Motor output-(efferent)
- Response is transmitted to effector (gland or muscle)
- Effector initiates actual response
Animal Organization
& Homeostasis
Neurons are not in direct contact with one
another instead, a synapse separates
them.
Neurons communicate with other neurons
by releasing chemical signals called
neurotransmitters across a tiny gap.
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Types of Neuroglial Cells
Schwann Cells
• peripheral nervous
system
• myelinating cell
Oligodendrocytes
• CNS
• myelinating cell
Microglia
• CNS
• phagocytic cell
Animal Organization
& Homeostasis
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Astrocytes
• CNS
• mop up excess ions, etc
• induce synapse formation
• stimulate formation of tight
junction between cells that make
up the walls of capillaries.
(Blood-brain barrier)
Ependyma
• CNS
• ciliated
• line central canal of spinal cord
• line ventricles of brain
•Regulate the production of CSF
Types of Neuroglial Cells
Animal Organization
& Homeostasis
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Animal Organization
& Homeostasis
Integumentary system-Skin and derivatives
Functions of skin: Largest organ in the body
Covers and protects underlying body regions
Regulate body temperature
Contains sensory receptor- touch, pressure
Vital in maintaining homeostasis
Epidermis - Outer, thinner region
Stratified squamous epithelium-lacks blood vessels
As new cells enlarge, older cells are pushed outward,
become keratinized, and are sloughed off
Melanocytes produce melanin (pigment)
Nails grow from specialized epidermal cells
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Regions of Skin
Animal Organization
& Homeostasis
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Dermis - Deeper and thicker than epidermis
Fibrous connective tissue containing elastic and
collagen fibers Contains:
- Hair follicles
- Sebaceous glands-secrete sebum
- Receptors-specialized nerve endings
- Nerve fibers
- Blood vessels
Subcutaneous Layer - Loose connective tissue
and adipose tissue located below dermis
Animal Organization
& Homeostasis
Human Skin Anatomy
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Organ Systems
Animal Organization
& Homeostasis
Body Cavities
 Dorsal cavity / posterior (toward the back)
- Contains the cranial cavity and the vertebral cavity
- The brain is in the cranial cavity, and
- The spinal cord is in the vertebral cavity
 Ventral cavity/ anterior (toward the front) is divided by the
diaphragm into
- The thoracic cavity (includes heart and lungs) and
- The abdominal cavity (most other internal organs)
- The pelvic cavity
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Animal Organization
& Homeostasis
Mammalian Body Cavities
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Homeostasis
Animal Organization
& Homeostasis
The organ systems of the human body contribute to
homeostasis
 The digestive system
- Takes in and digests food
- Provides nutrient molecules that re-place used nutrients
 The respiratory system
- Adds oxygen to the blood
- Removes carbon dioxide
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Homeostasis
Animal Organization
& Homeostasis
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The liver and the kidneys
- Store excess glucose as glycogen-regulates blood glucose
- Later, glycogen is broken down to replace the glucose used
- The hormone insulin regulates blood glucose levels
The kidneys
- Under hormonal control as they excrete wastes and salts
- Regulate pH
Negative Feedback
Animal Organization
& Homeostasis
Homeostatic Control
Partially controlled by hormones
Ultimately controlled by the nervous system
Negative Feedback is the primary homeostatic
mechanism that keeps a variable close to a set point
Sensor detects change in the internal environment;
Regulatory Center activates an effector
Effector reverses the changes
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Animal Organization
& Homeostasis
Regulation of Body Temperature
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Positive Feedback
Animal Organization
& Homeostasis
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During positive feedback, an event increases the
likelihood of another event-a change occurs in
one direction
Childbirth Process
Positive Feedback
Does not result in equilibrium
Does not occur as often as negative feedback
Review
Tissue Types
Epithelial
Connective
Muscular
Nervous
Organs
Organ Systems
Homeostasis
Negative Feedback
Positive Feedback
Animal Organization
& Homeostasis
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Ending Slide Chapter 33
Animal Organization
& Homeostasis