Ex 5 tissues Answers and Module for you PDF

Preview

Summary

it will help you to be aware so read it carefully...

Description

Human Anatomy and Physiology Laboratory Exercise 5

Tissues

Similar cells and intercellular matrix comprise tissues. The cell products, sometimes called intercellular matrix, oftentimes are used in classifying the tissue. Tissues could be solid or fluid while others can alter morphologically subject to the physiology condition of the organs. There are four fundamental tissues comprising the organ systems of the animal body. These include epithelia, muscle, connective and nerve tissues. Each organ in the body is composed of these four tissue types. Aims 1. Observe and distinguish the cellular and histological organization of epithelia, muscle, connective and nerve tissues. 2. Familiarize the functions of each tissue type.

Exercise5.1 Epithelial Tissues Epithelial tissues are made up of cells that are tightly-packed together leaving very little space for intercellular material or matrix. The epithelial cells rest in a non-cellular substance called the basement membrane. The cells are joined together by different types of cell anchoring or communication. Epithelial tissues are found primarily covering body surfaces and lining body cavities. Some epithelial tissues found in glands are specialized for secretion such as the glandular epithelia that secrete hormones or digestive enzymes. Epithelia are classified on the basis of the number of cell layers and the shape of the cells in the surface layer. If there is only one layer of cells in the epithelium, it is designated simple. If there are two or more layers of cells, it is termed stratified. Cells in the surface layer are, as a rule, described according to their height as squamous (scale- or plate-like), cuboidal or columnar. Some epithelia have cilia on their free surface which appear as fuzzy layer and known as ciliated epithelium. Stratified squamous can be keratinized (i.e. skin) or non-keratinized (i.e. esophagus). Pseudostratified columnar epithelium gives the illusion of several different layers of cells but is only one cell layer thick. All the cells touch the basement membrane, although not all cells reach the apical surface. Therefore, there are cells of different shapes and heights, and their nuclei are at different levels. Transitional cells change shape; the apical cells are cuboidal when the tissue is relaxed and squamous when the tissue is stretched. STUDENT ACTIVITY Materials  microscopes  prepared slides in cross sections (x-s): lung, kidney, vagina/esophagus, skin, urinary bladder/ureter, and trachea

small

intestine

(duodenum),

Procedure 1) Examine the demonstration slides of some types of epithelia. a) simple squamous – x-s of lung b) simple cuboidal – x-s of kidney c) simple columnar nonciliated – x-s of the small intestine d) ciliated pseudostratified columnar – x-s of trachea e) stratified squamous nonkeratinized – x-s of vagina or esophagus f) stratified squamous keratinized – x-s of the skin g) transitional epithelium – x-s of the urinary bladder or urethra 2) Draw the specimens in the lab report. basement membrane.

1

Note the cell membrane, cytoplasm, nucleus and

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory

Exercise5.2 Connective Tissues Connective tissues are made up of cells that are widely separated so the space in between are filled with intercellular matrix. Some biologists prefer to classify the connective tissues into the connective tissue proper (tendons, ligaments) and the specialized connective tissues (bones, cartilage, blood, adipose). Classification of connective tissues is based upon the arrangement of the intercellular matrix and the substance that make up the intercellular matrix. STUDENT ACTIVITY Materials  

microscopes prepared slides in cross sections (x-s) of tendon, dermis, areolar, cartilage, compact bone, adipose tissue and blood smear

Procedures 1. Examine the demo scope of a tendon. Look at the arrangement of the fibers. These fibers are predominantly collagen and the fiber-secreting cells in connective tissues are called fibroblasts. Draw the specimen and note the collagen fibers and fibroblast. Compare the fiber arrangement with that of dense irregular connective tissue by examining the demo scope of the dermis. 2. Examine the demo scope of an areolar connective tissue. Compare the arrangement of the fibers and the cells with those of the tendon. Draw the specimen and note the collagen fiber, elastic fiber and fibroblast. 3. Examine the demo scopes of cartilages. Note the location of the cartilage cells called chondrocytes inside the little cavities called lacunae. The substance between the cells or matrix is primarily chondroitin sulfate. Three types are observed in the human body – hyaline, elastic and fibrocartilage. Examine the different types. Draw the specimens and note the chondrocyte, lacuna and matrix. 4. Examine the demo scope of a blood smear. Notice the red blood cells (erythrocytes), white blood cells (leucocytes), and platelets (thrombocytes) present. Blood is one of the specialized connective tissue. The cells are far apart, and there is plenty of matrix in between the cells - the fluid portion of the blood called plasma. Draw the specimen and identify the erythrocyte, leucocyte, thrombocyte and plasma. 5. Examine the demo scope of a compact bone. The functional units of compact bones are called Haversian Systems. A Haversian system consists of the Haversian canal, the cavity in the center where blood vessels and nerves are found, the lacunae or little cavities where the bone cells called osteocytes are found, and the canaliculi or little canals that allow communications between osteocytes in neighboring lacunae. The lacunae are arranged in concentric circles or lamellae, and the substance in between is primarily salts of calcium and phosphorus in addition to collagen fibers. Draw the specimen and note the haversian canal, canaliculi, lamella (matrix) and osteocyte inside lacuna. 6. Examine the demo scope of adipose tissue. At first glance, the cells (adipocytes) appear empty. That is because the fat globules that fill the entire cytoplasmic region have been dissolved during the process of slide preparation. Draw the specimen and note the adipocyte and fat globule.

Exercise5.3

2

Muscle Tissues

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory Muscular tissues are designed for contraction and relaxation. The two major contractile proteins are actin, and myosin. Muscular tissues are classified based upon the organ where it occurs, the histological appearance of the cells, and the mode of enervation STUDENT ACTIVITY Materials  microscopes  prepared slides of skeletal, smooth (small intestine) and cardiac (heart) muscles Procedures 1) Examine the demo scope of small intestine. Note the small, spindle shaped cells that appeared to be piled one on top of the other. The cells do not have the striations ( smooth) characteristics of the other two types of muscles. It is occurs in the internal organs and is involuntary. Draw the specimen and label the muscle cell, nucleus and plasma membrane. 2) Examine the demo scope of a skeletal muscle. Note the prominent striations, parallel arrangement of long cylindrical muscle cells and peripheral nuclei. The name striated muscle is an allusion to the prominent transverse bands on the muscle fibers. These tissues are directly attached to the skeletal system. Contraction and relaxation of these muscles can be done at will (voluntary). Draw the specimen and label the muscle cell, nucleus and striations. 3) Examine the demo scope of a cardiac muscle tissue. This tissue is exclusively found in the heart (cardiac). It is also striated and branched. Intercalated disc are found at the point of branching. This tissue is involuntary. Draw the specimen and label the muscle cell, nucleus, intercalated discs and striations.

Exercise5.4 Nervous Tissue The nervous tissue is found primarily in the brain, spinal cord, as well as in ganglia and other organs of the body. The major type of cell is called neuron. It is designed to receive and transmit nerve impulses. Some nervous tissues are made up of modified cells such as the receptors in the skin and sensory organs. Materials  

microscopes prepared slides of cow nerve cells, spinal cord and cerebral cortex (brain)

Procedures 1) Examine the demo scope of cow nerve. Note the following: a) perikaryon or soma – cell body b) dendrites – long processes on the receptive surface of the neuron c) axon – emerges from the perikaryon, the "transmitting" process d) axon hillock – the point of origin of the axon from the perikaryon e) neuroglia – small cells around neurons 2) Examine the demo scope of the spinal cord. Note the white and gray matter. The white matter is composed of axons that are running to and from the brain, and the gray matter is composed of interneurons that make reflex decisions for the body. Cell bodies may be visible. 3) Examine the demo scope of a thin section of the cerebral cortex (part of the brain). Like the spinal cord, the brain is consists of white and gray matter. Note the density of neurons in an area.

3

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory

Lab Report 5

Tissues

Name: ________________________________ Class Schedule: _______________________

Score: _________________ Date Performed: _________

Results and Observation Exercise5.1 Epithelial Tissues Write the name of the epithelial tissue type that matches each description. An epithelial tissue type may be used more than once. ___________________ 1) Lines the mouth and protects underlying tissues in areas subject to abrasion. ___________________ 2) Located in the alveoli (the air sacs of the lung) and provides a short distance for the diffusion of oxygen and carbon dioxide. 3) Forms kidney tubules and is involved in absorption and secretion. ___________________ 4) Lines the nasal cavities and moves substances over the epithelial ___________________ surfaces. 5) Forms the mesothelium of the peritoneum and secretes serous fluid into ___________________ the peritoneal cavity. 6) Lines the stomach and its microvilli; increases surface area for ___________________ absorption and secretion. 7) Lines the bladder and ureter and is distensible. ___________________

Drawings Label the cell membrane, cytoplasm, nucleus, and basement membrane. Note also if cilia and goblet cells are present.

Type: ________________________

4

Type: ________________________

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory

Type: ________________________

Type: ________________________

Type: ________________________

Type: ________________________

Type: ________________________

Questions 1. What is the general function of simple epithelia? 2. What is the general function of stratified epithelia? 3. What is the general function of squamous epithelia? 4. What is the general function of cuboidal epithelia? 5. What is the general function of columnar epithelia?

Exercise5.2 Connective Tissues Write the name of the connective tissue type that matches each description. A connective tissue can be used more than once.

5

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory ___________________

___________________ ___________________ ___________________

___________________ ___________________

___________________ ___________________ ___________________

___________________ ___________________ ___________________

1) Contains elastic fibers and is found in the lungs. This tissue allows the lungs to inflate during inhalation and return to their original shape after exhaling. 2) Packed with parallel bundles of collagen fibers and found in tendons. This tissue resists pulling forces applied by muscles. 3) Has a firm, gelatinous ground substance containing collagen fibers. This tissue is found in the tracheal wall to support and prevent the trachea from collapsing. 4) Found under covering and lining epithelium. Its extracellular matrix contains a loose arrangement of fibers, and its viscous ground substance facilitates the flow of interstitial fluid containing nutrients to epithelial tissues. It also cushions and supports epithelia. 5) Contains many elastic fibers in a firm gelatinous ground substance. Located in external ear, auditory tube, and epiglottis. 6) Hard extracellular matrix forms trabeculae. 7) Forms a framework in the spleen, bone marrow, and lymph nodes. It contains fine, branching fibers. 8) Is packed with bundles of collagen fibers running in different directions. It is found in skin and allows skin to resist pulling forces from many different directions. 9) Fluid extracellular matrix used to transport substances throughout the body. 10) Contains a large number of lipid-storing cells. It is found throughout the body, cushions and insulates organs, and stores lipids for future energy needs. 11) Hard extracellular matrix containing osteons; involved in protection and support. 12) Firm gelatinous ground substance packed with bundles of collagen fibers. This tissue is found in intervertebral discs, pubic symphysis, and knee meniscus. 13) Fibers not present unless injury occurs. Extracellular matrix not produced by cells present in this tissue.

Drawings Identify the structures of the different connective tissues. Identify the collagen fiber and fibroblast.

-----------------------------------Tendon (Dense regular)

6

Identify the collagen fiber, elastic fiber and fibroblast.

-----------------------------------Areolar

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory Identify the collagen fiber and fibroblast.

-----------------------------------Dense irregular connective tissue (Dermis) Identify the chondrocyte, lacuna, elastic fibers and Identify the chondrocyte, lacuna and matrix. matrix.

-----------------------------------Hyaline cartilage

-----------------------------------Elastic cartilage

Identify the chondrocyte, lacuna and matrix.

-----------------------------------Fibrocartilage Identify the adipocyte and fat globule.

7

Identify the erythrocyte, leucocyte, thrombocyte and plasma.

-----------------------------------Blood (Vascular)

Identify the haversian canal, canaliculi, lamella (matrix) and osteocyte inside lacuna.

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory

-----------------------------------Adipose

-----------------------------------Osseous (Bone)

Questions 1. What is the function of fibroblasts in connective tissues? 2. What is the function of collagen in dense regular connective tissues like tendon and ligament? 3. Describe the function of the following structures of a compact bone: a. Haversian canal – b. canaliculus – c. lacuna – d. lamella – 4. Differentiate between the three types of cartilage (hyaline, elastic and fibrocartilage). 5. Why is blood a connective tissue? 6. What is the function of adipose tissues?

Exercise5.3 Muscle Tissues Write the name of the tissue that matches each function. For muscle tissue, write the name of the muscle tissue type. ___________________

1) Movement of urine through the urinary tract.

___________________

2) Movement of bone.

___________________

3) Movement of skin.

___________________

4) Movement of blood through the heart and into arteries.

___________________

5) Movement of food through the digestive tract.

___________________

6) Controls blood flow through arteries and veins and controls blood pressure.

8

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory Drawings Label the muscle cell, nucleus and plasma membrane.

Label the muscle cell, nucleus and striations.

----------------------------------------------------------------------Smooth muscle Skeletal muscle Label the muscle cell, nucleus, intercalated discs and striations.

-----------------------------------Cardiac muscle

Question Compare skeletal, smooth and cardiac muscle cells with regards to the following: Features a) shape of muscle cells b) number of nuclei per muscle cell c) location of nuclei d) presence of striations e) presence of branching

Exercise5.4

Skeletal Muscle

Smooth Muscle

Nervous Tissues

Identify the cell body, dendrites and axon.

9

Cardiac Muscle

Identify the white matter and gray matter.

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory

-----------------------------------Neuron

-----------------------------------Spinal cord (motor nerve)

Identify the neurons, glial cells, gray matter and white matter.

-----------------------------------Brain

Questions 1. In addition to the neurons, what other types of cells are present in nervous tissues. ___________ 2. Can you distinguish between a dendrite and an axon in a single neuron in the slide? ______ …. What is your basis? ________________ 3. Which matter of the spinal cord is more massive? ________________ ….What is the role of the white matter in the spinal cord? …. role of the gray matter? 4. Which matter in the brain has more neurons? ________________ …. has more glial cells? ________________

General Questions Primary Tissue Structure and Function Name the primary tissue type (epithelial, connective, muscle, or nervous) that is described. ___________________ ___________________ ___________________ ___________________ ___________________ ___________________

10

1) Cells contain processes that receive and generate electrical signals to communicate with other cells. 2) Tissue has elongated cells that shorten and cause movement. 3) Tissue contains more extracellular matrix than cells. 4) Cells either form a barrier that controls passage of molecules or form glands. 5) 6) Primary tissue types that exhibit cellularity.

Exercise 5: Tissues

Human Anatomy and Physiology Laboratory ___________________ ___________________ ___________________ ___________________ ___________________

11

7) 8) 9) Cells determine function of these primary tissue types. 10) 11) The extracellular matrix determines function of this primary tissue

Exercise 5: Tissues...