life sciences: animal tissue

35
Animal Tissues Prepared by: MOKWENA CATHY BUITUMELO

Transcript of life sciences: animal tissue

Animal Tissues

Prepared by:

MOKWENA CATHY BUITUMELO

Animal Tissues

• Cells form groups to produce specialized tissues that function together in a specific activity

• Classification: Epithelial tissues

Connective tissues

Muscular tissue

Nervous tissues

Connective TissueTypes of Connective Tissue

Loose (Areolar) Connective Tissue

Adipose

Blood

Fibrous Connective Tissue

Cartilage

Bone

Loose Connective Tissue Contain fibers and fibroblasts

Fibroblasts produce and secrete the fibers.

Loosely arranged in a semi fluid substance.

Acts as the framework for epithelium.

Forms a protective layer over muscle, nerves, and blood vessels.

Elastic Fibers

Collagen Fibers

Fibroblast nuclei

Adipose Tissue Adipose cells contain a large vacuole which in the live cell

contains lipids.

Cell nucleus and cytoplasm are pushed out to edge of cell membrane.

Adipose tissue has enlarged fibroblasts storing fats and reduced intracellular matrix.

Adipose tissue facilitates energy storage and insulation.

Blood connective tissue Red blood cells (erythrocytes) carry oxygen. White blood cells (leukocytes) function in the immune

system. Plasma transports dissolved glucose, wastes, carbon

dioxide and hormones, as well as regulating the water balance for the blood cells.

Platelets are cell fragments that function in blood clotting.

Blood connective

tissueBlood vessel

Red blood cells

White blood cells

Plasma

Platelets

Fibrous Connective Tissue Many fibers of collagen occurs in

Tendons, connect muscle to bone.

Ligaments connect bone to bone at a joint.

Contains elastic fibers that allow movement at joints

Muscular tissues

Smooth muscle

• These have long cells which have single nucleus.

• The cells of this muscle is spindle in shape.

• They are also called unstrained because we can not control them

Cardiac muscle

• It is the muscle which is present in heart.

• These muscle are also called involuntary muscle.

• These muscle have cylindrical &branched muscle.

Skeletal (striated) Muscle

These cells function in conjunction with the skeletal system for voluntary muscle movements.

Located in muscles that attach to bones.

Long, cylindrical cells are striated.

Cells are bundled closely together in parallel arrays.

Characteristics

Skeletal Smooth Cardiac

Location Attached to skeleton

Walls of internal organs

Walls of heart

Cross-striations Present Absent Present

Shape of fibers Cylindrical Spindle-shaped

Branched

Number of nuclei

Many or multinucleate

One or uninucleate

One or uninucleate

Position of nuclei

Peripheral Center Center

Type of control Voluntary Involuntary Involuntary

Speed of contraction

Most rapid slowest Intermediate

Nervous Tissue

Nerve (close-up view)

1. Endometrium

2. Epineurium

3. Axon

4. Schwann cell nucleus

5. Epineurium

3. Axon (nerve fiber)1. Myelin sheath

2. Neurilemma

3. Node of Ranvier

4. Schwann cell

5. Axon

Nervous tissues

• Neuron

• Cell body

• Processes

a. Axon

b. Dendrites

Nervous tissue consists of neurons, which are the cells that conduct signals, and supporting neuroglia

cells such as microglial cells, astrocytes and oligodendrocytes

Tissue Type Epithelial Connective Muscle Nerve

Cell ShapeFlattened, cuboidal, columnar

Irregular or round Elongated

Cell appendages

branched

Cell Arrangement

Single multilayered

Scattered in matrix

In sheets or bundles

Isolated or networked

LocationBody covering or lining organs

or cavities

Supports other organs

Lining internal organs, make

skeletal muscles

Concentrated in brain and spinal cord + all over the

body

Surface Feature of Cells Cilia, microvilli - - -

Matrix Type Basement membrane

Varied – protein fibers

+ liquid, gelatinous,

firm to calcified

- -

Matrix Amount Minimal Extensive Absent Absent

Unique FeatureNo direct blood supply, except

for glands

Cartilage has no blood supply

Can generate electrical

signals, force and movement

Can generate electrical

signal

Cartilage • Chondrocytes (cartilage cells)

• Avascular,  lacking blood vessels ---- does not possess the regenerative capacity

• contains a gelatinous ground substance called chondroitin sulphate

• Embedded within the GS are collagen & elastic fibers

• Together (chondroitin sulphate + fibers) -- flexible, yet very durable and also resistant to compression forces

• produced by chondroblasts through the process chondrification

• Types

a. Hyaline cartilage – most common type; in fatal skeleton, cartilaginous fishes

b. Elastic cartilage

c. Fibrocartilage

Blood

References

Bell, A. 1999. Anatomy 503 – Human Histology

http://faculty.une.edu/com/abell/histo/histolab2.htm

General Zoology Laboratory Manual, Biology Dept., Univ. of San Carlos

A/P Lab: A website for Human Anatomy and Physiology

http://bioweb.uwlax.edu/APlab/Index.htm

Ross, M., Romwell, L., and Kaye, G. 1995. Histology: A Text and Atlas. Williams and Wilkins, USA.

http://www.slideshare.net/itutor/animal-tissue-20032768?qid=9f7ec26b-d9b8-4566-9f10-b8593213dbd9&v=qf1&b=&from_search=4