11.1 Types of Tissues

• A tissue is composed of similarly specialized cells that perform a common function in the body.

11.1 Types of Tissues

• Four Types of Tissues in the Human Body

– Epithelial: lines body surfaces and cavities

– Connective: supports and bonds body parts

– Muscular: moves the body and its parts

– Nervous: receives stimuli and conducts impulses

11.1 Types of Tissues

• Epithelial tissue protects underlying structures;

functions may also include:

– Secretion (glands)

– Absorption

– Excretion

– Filtration

11.1 Types of Tissues

• Epithelial Tissue can be Classified According to Cell Type:– Squamous: Outer cells are flattened– Cuboidal: Outer cells are cubed shaped– Columnar: Outer cells are rectangular

• Epithelial Tissue can also be classified according to the number of layers in the tissue.– Simple: Single layer of cells– Stratified: Multiple cell layers

Epithelial Tissue

Junctions Between Epithelial Cells

11.1 Types of Tissues

• Connective Tissue– Binds organs together– Provides support and protection– Fills spaces– Produces blood cells– Stores fat

11.1 Types of Tissues

• Components of Connective Tissue

– Matrix: solid, semisolid, or liquid

– Fibers: collagen,elastic, reticular

– Cells: various types

11.1 Types of Tissues

• Connective Tissue Continued– Fibroblasts are cells that produce fibers and other

substances.

– Loose fibrous tissue support epithelium and many internal organs.

– Dense connective tissue is found in structures such as tendons and ligaments.

11.1 Types of Tissues

• Connective Tissue Continued

– Adipose Tissue• Fibroblasts enlarge and store fat

– Fat is used for energy, insulation, and organ protection

– Reticular Connective Tissue• Forms the meshwork of lymphatic tissue in:

– The spleen– The thymus– Bone marrow

11.1 Types of Tissues

• Connective Tissue Continued

– Cartilage• Cells lie in small chambers called lacuna

– Three Types of Cartilage• Hyaline: contains very fine collagen fibers • Elastic: has a higher proportion of elastic fibers, flexible• Fibrocartilage: contains strong collagen fibers

11.1 Types of Tissues

• Connective Tissue Continued

– Bone• The most rigid connective tissue• Consists of a matrix of calcium salts deposited around

collagen• Functions: Support, protection, mineral storage, blood cell

formation

– Two Types of Bone• Compact bone (shafts of long bones)• Spongy bone (end of long bones)

Examples of Connective Tissue

11.1 Types of Tissues

• Connective Tissue Continued

– Blood• Transports respiratory gases• Transports nutrients and wastes• Involved with many aspects of homeostasis• Helps protect us from disease

11.1 Types of Tissues

• Components of Blood

– Red Blood Cells• Contain hemoglobin for transport of oxygen

– White Blood Cells• Fight infection

– Platelets• Are cell fragments involved with blood clotting

Blood

11.1 Types of Tissues

• Muscular Tissue

– Muscle cells are called muscle fibers

– Muscles fibers contain actin and myosin filaments• Interaction of actin and myosin accounts for movements

– Types of Muscle Tissues• Skeletal• Smooth (visceral)• Cardiac

11.1 Types of Tissues

• Skeletal Muscle– Occurs in muscles attached to the skeleton– Cells are striated and multinucleated– Is voluntary

• Smooth Muscle– Occurs in blood vessels and walls of the digestive tract– Cells are spindle-shaped, each has a single nucleus– Striations are not present– Is involuntary

• Cardiac muscle– Occurs in the wall of the heart– Has branching, striated cells, each with a single nucleus– Is involuntary

Muscular Tissue

11.1 Types of Tissues

• Nervous Tissue– Neurons (nerve cells)

• Conduct impulses– Sensory input, integration, motor output

• Neuron structure– Dendrites– Cell body– Axon

– Neuroglia• Support and nourish neurons

– Microglia: phagocytic– Astrocytes: provide nutrients– Oligodendroglia: form myelin

Neurons and Neuroglia

11.2 Body Cavities and Body Membranes

• Cavities– Ventral Cavity- Divided by Diaphragm

• Thoracic cavity– Lungs– Heart

• Abdominal cavity– Visceral organs– Bladder– Reproductive organs

– Dorsal Cavity • Cranial cavity

– Brain

• Spinal cavity– Spinal cord

Mammalian Body Cavities

11.2 Body Cavities and Body Membranes

• Body Membranes– Mucous Membranes

• Line digestive, respiratory, urinary, and reproductive organs• Epithelium overlies loose fibrous connective tissue• Goblet cells-produce mucus• Protective function

– Serous Membranes• Line thoracic and abdominal cavities• Epithelium overlies loose fibrous connective tissue• Specific names according to location

– Pleural- lines thoracic cavity and lungs– Pericardial-encloses heart– Peritoneal- lines abdominal cavity and forms mesentery

11.2 Body Cavities and Body Membranes

• Body Membranes Continued

– Synovial membranes• Loose connective tissue• Line freely movable joints• Secrete synovial fluid

– Meninges • Line the dorsal cavity• Protect brain and spinal cord• Connective tissue

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.3 Organ Systems

11.4 Integumentary System

• The Integumentary System – Skin– Hair– Nails– Sweat Glands– Sebaceous Glands

11.4 Integumentary System

• Functions of the Integumentary System – Protects underlying tissues from trauma, pathogen

invasion, and water loss

– Helps to regulate body temperature

– Synthesizes Vitamin D

– Helps us to be aware of our surroundings

11.4 Integumentary System

• Regions of the Skin– Epidermis

• Stratified squamous epithelium• Basal layer produces new cells• Cells harden and die as they push to the surface• Keratin - hardens cells, waterproof• Melanocytes - produce pigment

11.4 Integumentary System

• Regions of the Skin– Dermis

• Contains collagen fibers that help prevent tearing• Contains elastic fibers that maintain tension• Contains blood vessels that nourish the skin• Contains sensory receptors for touch, pain, pressure,

temperature

11.4 Integumentary System

• Subcutaneous Layer

– Loose connective tissue

– Adipose tissue• Insulation

• Energy storage

Human Skin Anatomy

11.4 Integumentary System

• Accessory Organs of the Skin– Nails

• Protect digits• Nail root- grows new nail• Cuticle- protects nail root• Lunula- white half-moon at base- thick layer of cells

Nail Anatomy

11.4 Integumentary System

• Accessory Organs of the Skin– Hair Follicles

• Extend from dermis through epidermis• Arrector pili muscles-erect hair shaft- “goose bumps”• Epidermal cells in hair root form hair• Cells become keratinized and die as they are pushed away

from root

– Oil Glands• Associated with hair follicles• Lubricates hair and skin

– Sweat Glands• Some open into hair follicles, others onto skin• Thermoregulation

11.5 Homeostasis

• Homeostasis is the relative constancy on the body’s internal environment.

• Even if external conditions change dramatically, internal conditions stay within a narrow range.

11.5 Homeostasis

• Negative Feedback

– Primary mechanism that keeps a variable close to a set point.

– Two components (minimum)• A sensor• A control center

Negative Feedback Mechanism

Negative FeedbackA Mechanical Example A Human Example

11.5 Homeostasis

• Positive Feedback– A change brings about a greater change in the same

direction• Example: A fever brings about changes in the

body that cause body temperature to increase even more (can be fatal)

• Beneficial examples include blood clotting and the birthing process

11.5 Homeostasis

• Homeostasis and Body Systems– The Transport Systems

• Cardiovascular system-pumps blood to and from capillaries for exchange

• RBC’s- carry oxygen• Platelets-clotting• Lymphatics-collect excess tissue fluid / Purify Lymph

– The Maintenance Systems• Respiratory system-brings in oxygen and removes carbon

dioxide• Digestive system-digests nutrients and removes wastes• Liver- manufactures products, detoxifies• Kidneys- fluid balance, pH regulation, waste removal

Regulation of Tissue Fluid Composition

11.5 Homeostasis

• Homeostasis and Body Systems Continued– The Support Systems

• Integumentary system produces vitamin D• Skeletal system stores minerals, produces blood cells• Muscular system produces heat

– The Control Systems• Nervous system and endocrine system function as control

centers• Direct effectors to become active

– Muscles– Glands

11.5 Homeostasis

• Disease– Breakdown in self regulation– Body no longer functions properly– Local disease

• Restricted to one part of the body

– Systemic disease• Affects entire body

– Acute disease• Occur suddenly• Usually short duration

– Chronic disease• Long term, less severe• Develop slowly