BODY SYSTEMS BODY TISSUES AND MEMBRANES

TISSUES Cell are grouped according to their similarities; groups are called tissues 4 types of tissues: 1. Epithelial 2. Connective 3. Muscle 4. Nervous

EPITHELIAL TISSUE Protects the body by covering internal and external surfaces Absorbs nutrients in the lining of the small intestine Makes up all glands Excretes sweat Named according to it’s structure

EPITHELIAL TISSUE Covering and lining tissue – Squamous epithelial cells: flat, irregularly shaped – Cuboidal epithelial cells: cube-shaped cells – Columnar epithelial cells: elongated, with the nucleus near the bottom and ciliated on the outer surface Glandular or secretory tissue – Endocrine gland cells: secrete hormones directly into the bloodstream – Exocrine gland cells: secrete their substances into ducts

CONNECTIVE TISSUE Connects organs and tissue Allows for movement and provides support for other types of tissue Classified into 3 subgroups – Loose connective tissue – Dense connective tissue – Specialized connective tissue

CONNECTIVE TISSUE Loose – Adipose tissue: specialized for the storage of fat – Areolar tissue: supports both nerve cells and blood vessels which transport nutrients and waste Dense – Ligaments: strong, flexible bands which hold bones firmly together at the joints – Tendons: white, glistening bands attaching skeletal muscles to the bones – Cartilage: provides firm but flexible support for the embryonic skeleton and part of the adult skeleton Specialized

MUSCLE TISSUE Contains cell material which has the ability to contract and move the body – Cardiac muscle: contract and enable the heart to pump blood throughout and out of the heart – Skeletal muscle: attached to the movable parts of the skeleton; capable of rapid, powerful contractions and long states of partially sustained contractions, allowing for voluntary movement – Smooth muscle: provide for involuntary movement

NERVOUS TISSUE Contains cells that react to stimuli and conduct an impulse Controls and coordinates body activities, controls our emotions, and allows us to learn through the memory process Includes the special senses of sight, taste, touch, smell, and hearing needs

TISSUE CELLS Epithelial cells that cover the body’s external and internal surfaces have a typical shape (either columnar, cubical, or platelike); allows the cells to fit together smoothly in order to line and protect the bodily surface Muscle cells are long and spindlelike so they can contract

PAUSE NOW TO READ TABLE 4-1 pgs

MEMBRANES Formed by putting 2 thin layers of tissue together. The cells in the membrane may secrete a fluid Classified as epithelial or connective

EPITHELIAL MEMBRANES Classified as either mucous or serous membranes, depending on the type of secretions produced Look at Figure 4-1 pg 61

MUCOUS MEMBRANES Line surfaces and spaces that lead to the outside of the body Line the respiratory, digestive, reproductive, and urinary systems Produces mucous which lubricates and protects the lining Mucosa is a term for specific mucous membranes

MUCOSA Respiratory mucosa: lines the respiratory passages Gastric mucosa: lines the stomach Intestinal mucosa: lines the small and large intestines

SEROUS MEMBRANES Double-walled membrane that produces a watery fluid that lies closed body cavities Fluid is called serous fluid; allows the organs within to move freely and prevents friction Parietal membrane: outer part of the membrane that lines the cavity Visceral membrane: part that covers the organs within Serosa: term for specific serous membranes (all begin with the letter “p”)

SEROSA Pleural membrane: lines the thoracic or chest cavity and protects the lungs; fluid is pleural fluid Pericardial membrane: lines the heart cavity and protects the heart; fluid is pericardial fluid Peritoneal membrane: lines the abdominal cavity and protects the abdominal organs; fluid is peritoneal fluid

CONNECTIVE MEMBRANES Consist of 2 layers of connective tissue Synovial membrane lines the joint cavities and secrete synovial fluid which prevents friction inside the joint cavity

ORGANS Structure of several types of tissues grouped together to perform a single function Organelles: cell structures that help a cell with its special function or capacity (pg 34) For example: stomach is an organ that consists of highly specialized vascular, connective, epithelial, muscular, and nerve tissues. All function together to enable the stomach to digest and absorb

ORGANS continued Organs do not function separately They coordinate their activities to form a complete, functional organism. Organ system: a group of organs that act together to perform a specific, related function

ORGAN SYSTEMS Example: Digestive system has the special function of processing solid food into liquid for absorption into the bloodstream System includes: mouth, salivary glands, esophagus, stomach, small intestine, liver, pancreas, gall bladder, and large intestine

LOOK AT FIGURE 4-2 pg 63

ORGAN SYSTEMS The human body has 10 (pg 64, Table 4-2) Each is highly specialized to perform a specific function Together they coordinate their functions to form a whole, live, functioning organism…US

1. SKELETAL Gives shape to the body Protects delicate parts of the body Provides space for attaching muscles Instrumental in forming blood. WHY? Stores minerals (i.e. calcium) Organs: skull, spinal column, ribs and sternum, shoulder girdle, upper and lower extremities, pelvic girdle

MUSCULAR Determines posture Produces body heat Provides for movement Organs: striated voluntary muscles, skeletal striated involuntary muscles, cardiac smooth muscles, nonstriated

DIGESTIVE Prepares food for absorption and use by body cells through modification of chemical and physical states Organs: mouth (salivary glands, teeth, tongue), pharynx, esophagus, stomach, intestines, liver, gallbladder, pancreas

RESPIRATORY Acquires oxygen Rids body of carbon dioxide Organs: nose, pharynx, larynx, trachea, bronchi, lungs

CIRCULATORY Carries oxygen and nourishment to cells of the body Carries waste from cells Provides body defense. HOW? Organs: heart, arteries, veins, capillaries, lymphatic vessels, lymph nodes, spleen

EXCRETORY Removes waste products of metabolism from the body Organs: skin, lungs, kidneys, bladder, ureters, urethra

NERVOUS Communicates Controls body activity Coordinates body activity Organs: brain, nerves, spinal cord, ganglia

ENDOCRINE Manufactures hormones to regulate organ activity Organs: glands (ductless): pituitary, thyroid, parathyroid, pancreas, adrenal, gonads (ovaries and testes)

REPRODUCTIVE Reproduces human beings Male organs: – Testes – Scrotum – Epididymis – Vas deferens – Seminal vesicles – Ejaculatory duct – Prostate gland – Cowper’s gland – Penis – Urethra Female organs: – Ovaries – Fallopian tubes – Uterus – Vagina – Bartholin’s gland – External genitals (vulva) – Breasts (mammary glands)

INTEGUMENTARY Helps regulate body temperature Establishes a barrier between the body and environment Eliminates waste Synthesizes vitamin D Contains receptors for temperature, pressure, and pain Organs: epidermis, dermis, sweat glands, oil glands