Principles of Biology BIOL 100C: Introductory Biology III Animal Cells & Tissues Dr. P. Narguizian Fall 2012

THE HIERARCHY OF STRUCTURAL ORGANIZATION IN AN ANIMAL Copyright © 2009 Pearson Education, Inc.

Structure fits function at all levels of organization in the animal body  Anatomy—structure  Physiology—function  Animals consist of a hierarchy of levels or organization Copyright © 2009 Pearson Education, Inc.

Cellular level Muscle cell Tissue level Muscle tissue Organ level Heart Organ system level Circulatory system Organism level Many organ systems functioning together A B C D E

Tissues are groups of cells with a common structure and function Copyright © 2009 Pearson Education, Inc.  Animals have four main categories of tissues –Epithelial tissue –Connective tissue –Muscle tissue –Nervous tissue

EpithelialConnective Muscle Nervous Neurons with branching extensions Long cells (fibers) with contractile proteins Sparse cells in extracellular matrix Sheets of closely packed cells Protection, exchange, secretion Binding and support of other tissues Movement of body parts Transmission of nerve signals Function Structure Tissue

Epithelial tissue covers the body and lines its organs and cavities  Epithelial cells come in three shapes –Squamous—like a fried egg –Cuboidal—as tall as they are wide –Columnar—taller than they are wide Copyright © 2009 Pearson Education, Inc.

Epithelial tissue covers the body and lines its organs and cavities  Epithelial cells come in different arrangements –Simple –Stratified Copyright © 2009 Pearson Education, Inc.

Apical surface of epithelium Cell nuclei Underlying tissue Basal lamina Simple squamous epithelium (air sacs of the lung) Simple cuboidal epithelium (kidney) Simple columnar epithelium (intestine) Stratified squamous epithelium (esophagus) Pseudostratified ciliated columnar epithelium (respiratory tract) A B C D E

Fat droplets Adipose tissue White blood cells Red blood cell Blood Plasma Loose connective tissue (under the skin) Elastic fibers Collagen fiber Cell Fibrous connective tissue (forming a tendon) Collagen fibers Cell nucleus Cartilage (at the end of a bone) Matrix Cartilage- forming cells Central canal Matrix Bone- forming cells Bone B A F E D C  Connective tissue can be grouped into six major types

Muscle tissue functions in movement  Skeletal muscle causes voluntary movements  Cardiac muscle pumps blood  Smooth muscle moves walls of internal organs, such as the intestines Copyright © 2009 Pearson Education, Inc.

Unit of muscle contraction Muscle fiber Nucleus Muscle fiber Junction between two cells Nucleus Muscle fiber Cardiac muscle Smooth muscle Skeletal muscle C B A

Nervous tissue forms a communication network  Neurons carry signals by conducting electrical impulses  Supporting cells insulate axons and nourish neurons Copyright © 2009 Pearson Education, Inc.

Cell body Nucleus

Organs are made up of tissues  Each tissue performs specific functions  The heart has epithelial, connective, and nervous tissues –Epithelia line the heart chambers –Connective tissues make the heart elastic –Neurons regulate contractions Copyright © 2009 Pearson Education, Inc.

Small intestine Lumen Epithelial tissue Connective tissue Smooth muscle tissue (2 layers) Connective tissue Epithelial tissue (columnar epithelium) Lumen

Organ systems work together to perform life’s functions  An organ system usually consists of many organs  Each organ system has one or more functions Copyright © 2009 Pearson Education, Inc.

 Endocrine system controls body functions  Skeletal and muscular systems support and move the body  Circulatory system transports the food and oxygen  Respiratory system absorbs oxygen and releases carbon dioxide  Integumentary system covers and protects the body Copyright © 2009 Pearson Education, Inc. Organ systems work together to perform life’s functions

Circulatory system Heart Blood vessels Respiratory system Nasal cavity Larynx Trachea Bronchus Lung Muscular system Integumentary system Hair Nails Skin Skeletal muscles Cartilage Bone Skeletal system Adrenal gland Pancreas Testis (male) Ovary (female) Hypothalamus Pituitary gland Thyroid gland Parathyroid gland Endocrine system C D F E B A

 Excretory system disposes of certain wastes  Lymphatic and immune systems protect the body from infection and cancer  Reproductive system perpetuates the species  Digestive system absorbs food  Nervous system controls body functions Copyright © 2009 Pearson Education, Inc. Organ systems work together to perform life’s functions

Lymphatic and immune systems G, H Thymus Bone marrow Spleen Oviduct Ovary Female Lymph nodes Lymphatic vessels Uterus Vagina Urinary system Male Brain Seminal vesicles Prostate gland Vas deferens Penis Urethra Testis Sense organ Spinal cord Nervous system Nerves Esophagus Liver Stomach Small intestine Digestive system Large intestine Anus Mouth Kidney Ureter Urinary bladder Urethra K J I L Reproductive system

The integumentary system protects the body  The skin consists of two layers –Epidermis, at the surface –Dermis, inner layer Copyright © 2009 Pearson Education, Inc.

Epidermis Dermis Hypodermis Adipose tissue Blood vessels Hair follicle Oil gland Sweat gland Sweat pore Hair Muscle Nerve

 Skin has many functions –Epidermis –Resists damage –Decreases water loss –Prevents penetration by microbes –Dermis –Sensory information –Synthesis of vitamin D –Temperature regulation Copyright © 2009 Pearson Education, Inc. The integumentary system protects the body

EXCHANGES WITH THE EXTERNAL ENVIRONMENT Copyright © 2009 Pearson Education, Inc.

Structural adaptations enhance exchange between animals and their environment  Animals must exchange materials with the environment  Respiratory system exchanges gases  Digestive system acquires food and eliminates wastes  Excretory system eliminates metabolic waste Copyright © 2009 Pearson Education, Inc.

External environment Mouth Food Animal CO 2 O2O2 Respiratory system d Bl oo Digestive system Heart Nutrients Circulatory system Intestine Urinary system Body cells Interstitial fluid Anus Unabsorbed matter (feces) Metabolic waste products (urine)

 Adaptations that increase surface area promote exchanges with the environment Copyright © 2009 Pearson Education, Inc. Structural adaptations enhance exchange between animals and their environment

 Homeostasis is an internal steady state Animals regulate their internal environment Copyright © 2009 Pearson Education, Inc.

External environment Homeostatic mechanisms Internal environment Small fluctuations Large fluctuations

 Humans promote homeostasis by –Adding clothing when we are cold –Drinking water when we are dehydrated –Eating when our calories are running low –Urinating when our bladders are full Copyright © 2009 Pearson Education, Inc. Animals regulate their internal environment

Sweat glands secrete sweat that evaporates, cooling body Blood vessels in skin dilate and heat escapes Temperature decreases Thermostat shuts off cooling mechanisms Temperature rises above normal Temperature falls below normal Thermostat shuts off warming mechanisms Homeostasis: Internal body temperature of approximately 36–38°C Temperature increases Blood vessels in skin constrict, minimizing heat loss Skeletal muscles rapidly contract, causing shivering, which generates heat Thermostat in brain activates warming mechanisms Thermostat in brain activates cooling mechanisms  Negative feedback mechanisms permit only small fluctuations around set points

Let’s test your knowledge…

EpithelialConnective Muscle Nervous Neurons with branching extensions Long cells (fibers) with contractile proteins Sparse cells in extracellular matrix Sheets of closely packed cells Function Structure Tissue

a. b. c. d. e.

You should now be able to  Explain the relationship between anatomy and physiology  Describe the structural hierarchy of the body from cell to organism  Explain how an animal’s form is influenced by its environment  Describe an example of convergent evolution  Describe the general structures and functions of the major tissues of the human body Copyright © 2009 Pearson Education, Inc.

 List and describe the functions of the major systems of the body  Explain how materials are exchanged between an organism and its environment  Define homeostasis and describe several examples Copyright © 2009 Pearson Education, Inc. You should now be able to