Unit 5

Lesson One

Chapter 15

Lesson 1

Your skin has two main layers which include the epidermis – the outer, thinner layer of your skin, and the dermis – the inner, thicker layer of your skin.

The epidermis is made of both dead and living cells. New cells arise to the surface to

replace the old ones. Some of the cells in the epidermis

produce melanin, the pigment that gives skin, hair and the iris

of the eyes their coloring. Melanin determines the color in

your skin.

The dermis is made up of connective tissue that gives

the skin its elasticity, or spongy, flexible quality.

Under the dermis is tissue called the hypodermis. Although it is not part of

your skin, it attaches your skin to the bone and

muscle.

Structure of the Skin

Functions of the Skin

Lesson 1

Providing a Protective Covering for your Body

Your skin shields you from injury, invasion by pathogens, and the sun’s harmful ultraviolet (UV) rays. Your skin is the main divider between your internal organs and the outside world. It is also waterproof and has a water-holding capacity.

Regulating Body Temperature

Skin keeps body temperature constant. Radiation is a process when tiny blood vessels in the skin enlarge, permitting internal heat to escape. This happens when your body is hot and sweat glands also become active, releasing perspiration, which cools the skin as it evaporates. You conserve body heat as your internal temperature drops because of how the blood vessels narrow.

Enabling you to Sense the World Around you

Skin serves as a means of communication with the outside environment. Nerve endings respond to touch, pain, pressure and temperature.

Skin Care and Problems With the SkinLesson 1

Some common problems with the skin are as followed:

•Acne

•Ringworm

•Athlete’s foot

•Boils

•Warts

•Moles

•Psoriasis

•Vitiligo

•Impetigo

•Blisters

•Callus

•Corn

The skin should be washed every morning and evening with soap and water. A balanced eating style should also be used to promote

healthy skin. Everyone needs to bathe, wash, or shower daily to prevent bacteria that causes body odor. Vitamin A also helps with your health and some items that include this are: milk, egg yolks,

liver, green leafy and yellow vegetables, and yellow fruits.

Lesson 2

Lesson 2

Functions

The skeleton provides a strong, stable, and mobile

framework on which muscles can act. It also supports and protects your internal organs.

Structure

Axial skeleton:

-includes the 80 bones of the skull, spine, ribs, and

sternum

-the vertebrae protect your spinal cord

-The ribs protect your lungs and heart

Appendicular skeleton:

-includes the 126 bones of the shoulders, arms, hands,

hips, legs and feet

Joints

The point at which two bones meet is a joint. Most joints

allow a wide range of movement. There are several

types of mobile joints:

•Ball-and-socket joint

•Pivot Joint

•Ellipsoidal joint

•Hinge joint

Ligaments are tough bands of fibrous, slightly elastic

tissue that bind the bone ends at the joint. Ligaments also

prevent excessive movement of the joint. Tendons are

fibrous cords that join muscle to bone or to other muscles.

Care

Calcium is an important mineral found in dairy

products essential for building strong bones. Phosphorus is

another vital mineral that gives your bones their rigidity.

Exercise promotes better blood circulation which

increases nourishment to you bones.

ProblemsFractures are any type of break

in your bone. Some include:

•Hairline fracture

•Transverse fracture

•Comminuted fracture

Injuries of joints include:

•Dislocation

•Torn cartilage

•Bunion

•Bursitis

•Arthritis

Lesson 3

Lesson 3

FunctionsWithout muscles, nothing in

your body would work. Muscles pump blood through

your body, move food through your digestive system, and control the

movement of air in and out of your lungs.

StructureThe major muscles are:

Smooth muscles: the type of muscle concerned with the movements of internal organs

Skeletal muscles: the striped, or striated, muscles attached to bones that cause body movements

Cardiac muscle: a special type of striated tissue that forms the walls of the heart

Care

To maintain muscle tone, you need to keep active and eat

nutritious meals.

Structure•Myasthenia Gravis: muscles become weak and easily fatigued

•Muscular Dystrophy: an inherited disorder characterized by a progressive wasting away of skeletal muscles

Injury-Related Muscular Problems

•Muscle strain: a tearing or stretching of muscle fibers as a result of suddenly pulling them too far

•Bruise: a discolored area under the skin caused by leakage of blood after an injury

•Tendinitis: the inflammation of a tendon

•Hernia: a protrusion of an organ or tissue through a weak area in the muscle

Chapter 16

Lesson 1

Lesson 1

FunctionYour nervous system controls

all your body’s actions and functions.

StructureCentral Nervous System:

receives and analyzes information and initiates

responses. Includes the spinal cord and brain.

Peripheral Nervous System: gathers information from inside

and outside of your body.

The Brain StemA 3-inch-long stalk of nerve

cells and fibers that connect the spinal cord to

the rest of the brain.

Includes the:

•Medulla oblongata: the lowest part of the brain stem

•Pons: pathway for nerve impulses passing to and from the cerebrum

•Midbrain: shortest part of the brain stem

•Thalamus: an important relay center for incoming sensory impulses

•Hypothalamus: keeps body conditions balanced

Reflex ActionA spontaneous

response of the body to a stimulus.

Lesson 2

Care of the Nervous SystemTo keep your nervous

system functioning well, you need:

-Regular exercise

-Proper nutrition

-Adequate rest and sleep

ProblemsAccidents can damage or

destroy nerve tissue Degenerative diseases

can destroy nerve tissue in the brain or spinal

column. Drug and alcohol use can lead to nervous

system disorders.

Head InjuriesAny direct blow to the head can lead to possible brain

injury. A concussion, a temporary disturbance of the brain’s ability to function, is

the most common and mildest kind of brain injury. A

contusion is more serious though and can result in a

coma.

Spinal InjuriesInjury on the spinal cord can lead to paralysis. An injury at

neck level may result in quadriplegia and paralysis is in both the arms and legs. Injury at the chest level or lower affects the legs and

lower body.

Degenerative Diseases

Parkinson’s disease: caused by degeneration of the nerve cells within the brain that modify nerve impulses transmitted from the motor areas of the brain.

Multiple sclerosis: the destruction of the myelin sheath that surrounds nerve fibers in the brain and spinal cord.

Alzheimer’s disease: causes general mental deterioration

Other DisordersEpilepsy: a disorder of the nervous system that is characterized by seizures

Cerebral Palsy: a group of nonprogressive neurological disorders that are the result of damage to the brain before birth, during birth, in the newborn period, or in early childhood.

Lesson 3

StructureThe principal structures are the endocrine glands which are

ductless structures that secrete hormones. Hormones are

chemical substances produced by ductless glands that regulate the activities of different body cells.

GlandsPituitary Gland: regulates and controls the activities of all other endocrine glands.

Thyroid Gland: produces hormones that regulate metabolism-the use of nutrients by the body’s cells-body heat production, and bone growth.

Parathyroid Glands: structures that produce parathyroid hormone, which regulates the body’s calcium and phosphorus balance.

Adrenal Glands: two glands located on the top of the kidneys.

The PancreasThe pancreas is a gland that serves two systems-the digestive and the endocrine. It is located behind the

stomach, attached to the first section of the small intestine by a duct that transports its digestive

juice to the intestine.

The GonadsOf all the endocrine glands, only the

gonads are different in males and females. The ovaries (female) and

testes (males) are apart of the reproductive system. The ovaries produce and release ova, and the testes produce and release sperm.

Gonads play a huge part in the process of the reproductive system which will be discussed in chapter

19.

ProblemsMost of the disorders are related to the production of too much or too little of hormone. Some disorders include:

•Diabetes Mellitus: a disorder in which the pancreas produces too little or no insulin.

•Graves’ Disease: an autoimmune disorder in which the thyroid gland becomes overactive and enlarged, producing excessive amounts of thyroid hormones.

•Crushing’s Disease: overproduction of adrenal hormones

•Goiter: and enlargement of the thyroid gland

Growth DisordersIf the anterior lobe of the pituitary gland does not produce enough of the growth hormone, a person does not grow. The person’s stature is short although the bones are usually in normal shape.

Chapter 17

Lesson 1

FunctionsYour circulatory system maintains an internal environment in which

all the calls of you body are nourished. As your heart pumps

blood, blood vessels carry oxygen and nutrients to body cells. At the

same time another gas carbon dioxide, is carried along with

waste matter from your cells and delivered to your lunges and kidneys for removal from the

body.

Structure The main parts of the

circulatory system are your heart, blood, arteries, veins

and capillaries.

•The heart-Along with your brain, your heart is the most important part of your body's vital organs. The brain never rests; the muscular pump beats continuously to send blood to the and the rest of the body.

•Blood- The fluid that transports all the substances that your body needs to sustain life. Blood delivers oxygen, hormones, and nutrients to the cells and carries away wastes that the cells produce. About 55% of the total volume of blood is made up of plasma the fluid in which the other parts of blood are suspended.

The Lymphatic systemYour body's circulatory system

is supported by a second network known as the lymphatis system. This system serves to functions. It drains tissue fluid

back into the bloodstream, and it fights infection. All body tissues are bathes in watery fluids that

comes from the blood. The remainder is carried to the heart through the lymphatic system. The lymphatic system is your

second circulatory system. The fluid is circulated through your

body’s muscles.

Care of the Circulatory and Lymphatic System

Smoking puts added stress on your circulatory system. It increases

blood pressure and heart rate by narrowing arteries. Being

overweight is linked to high blood pressure and coronary heart disease, so maintaining an

appropriate weight is important. Everyone should also have an

aerobic exercise 3 times a week for 20 minutes and regular check ups

are important too.

Lesson 2

Blood Pressure

Blood pressure is the force of blood in the main arteries. It rises and falls

as the heart and muscles of the body cope with varying demands.

When arterial pressure is at its greatest, it is called systolic pressure. When the arterial

pressure is at its lowest, it is called diastolic pressure.

Circulatory System Problems

•Congenital Heart Disease•Heart Murmur•Varicose Veins•Anemia•Leukemia•Hemophilia

Lymphatic System Problems

•Immune Deficiency

•Hodgkin’s Disease

•Tonsillitis

Respiratory System

•The main function of the respiratory system is respiration – the exchange of gases between your body and your environment

•There are two major parts to respiration – internal (exchange of gases between blood and cells) and external (the exchange of oxygen and carbon dioxide)

•Your main structures are the lungs and structures within the nose and mouth

•Your lungs take in oxygen from the air you inhale and return carbon dioxide to the air when you exhale

•When you inhale, your rib muscles and diaphragm contract

•From your nose, air moves through the pharynx, or throat, and into the trachea, or windpipe.

•To avoid risk of infection, you need to keep from putting your hands up to your nose and mouth.

Respiratory System ProblemsThe respiratory system is a common site of infection. Some more serious

infections of it are:

Bronchitis

Asthma

Pneumonia

Tuberculosis

Emphysema

Sinusitis

Chapter 18

Lesson 1

The Digestive System

Functions

Digestion- the mechanical and chemical breakdown of foods for use by the body’s cells.

Absorption- the passage of digested foods from the digestive tract into the circulatory system.

Elimination- the expulsion of undigested food or body wastes

Structure

Digestion begins before you take a bite of food when the aroma of food

activates the salivary glands.

The Mouth and Teeth

The primary function of your teeth is to break food you eat into smaller pieces. Mastication is the process

of chewing.

Organs That Aid Digestion

The Liver

The Gallbladder

The Pancreas

Care of the Digestive System

Good eating habits are the best way to avoid or minimize digestive

system problems.

•Eat a variety of foods.

•Avoid an overabundance of fried foods.

•Do not hurry through your meals-eat slowly while sitting down.

•Do not wash your food with liquid. Wait until you are finished chewing-swallow, and then take a sip of liquid

•Drink plenty of water!

•Do not eat when you are under stress.

Problems

•Indigestion

•Heartburn

•Gas

•Nausea

•Diarrhea

•Constipation

•Gallstones

•Appendicitis

•Gastritis

•Lactose Intolerance

•Peptic Ulcer

•Colitis

•Hemorrhoids

•Tooth Decay

The Urinary System

The chief function of the urinary system is to remove water soluble

waste products that result from chemical changes to cells. Urine contains nitrogen and, therefore, would become toxic if allowed to

remain in your body.

Your bladder is a hollow, muscular organ that acts as a reservoir for

urine. Care of the urinary system is to regularly drink fluids and to have

a well-balanced eating style.

Problems of the Urinary system is Cystitis-a bacterial infection of the

bladder that occurs mostly in females and Urethritis- an

inflammation of the urethra.

Lesson 3

Chapter 19

Function and Structure of the Male Reproductive System•During the early teen years, the male reproductive system reaches maturity

•Hormones released by the pituitary gland stimulate the testes and begin producing the male sex hormone testosterone.

•Testosterone initiates physical changes and causes the production of sperm, male reproductive cells.

•The production of sperm and the transfer of it to the female’s body during sexual intercourse are the two main biological functions of the male reproductive system.

External Male Reproductive Organs•The main external organs are the testes and the penis.

•Also known as testicles, the testes are two small glands that produce sperm at the rate of 100 million per day.

•The testes hang outside the body in a sac called the scrotum.

•The penis is a tube-shaped organ attached to the trunk of the body just above the testes.

•During ejaculation, semen-a thick fluid containing sperm and other secretions from the male reproductive organs-is propelled from the penis.

•If this happens during sexual intercourse, fertilization-the union of a reproductive cell from a male and one from a female-may be initiated.

•At birth, the tip of the penis is covered with a fold of skin called foreskin so some parents choose to have their child circumcized.

Internal Male Reproductive Organs•The tubes in each testis join a larger coiled tube which is called the epididymis which is a temporary storage facility for sperm.

Care of the Male Reproductive System•Care of the male reproductive system involves cleanliness, protection, and self-examination.

•Males should shower daily, completely cleansing the penis and scrotum.

•Males should avoid overly tight clothing and wear a protector during strenuous activity.

•Once a male if physically mature, he should perform monthly self-examinations of his testes to check for any signs of cancer.

Problems

Hernia

Sterility

Enlarged Prostate Gland

Cancer of the Prostate Gland

Cancer of the Testes

Functions and Structure of the Female Reproductive System•The primary biological functions of the female reproductive systems are related to the process of reproduction.

•It stores female reproductive cells, or ova and nourishes and protects each fertilized ovum from the beginning of pregnancy through birth.

•Sperm from the male enter the female reproductive system through the vagina, a muscular, elastic passageway that extends from the uterus to the outside of the body.

Female Reproductive Organs•Ova are stored in the ovaries, the female sex glands that house the ova and produce female sex hormones.

•During early teen years, hormones cause immature ova to mature and ovaries begin the process of releasing one mature ovum each month which is called ovulation.

•When it is released from an ovary, it moves into one of the fallopian tubes. These are a pair of tubes with fingerlike projections that draw the ovum in.

•If a sperm cell introduced during intercourse is present in the fallopian tubes, it may unite with an ovum and fertilization occurs. The result of the union of sperm and an ovum is a zygote.

•The uterus is a small, muscular, pear-shaped organ, about the size of a fist. When a zygote is formed, it attaches itself to the uterine wall.

Care and Problems of he Female Reproductive System•Cleanliness is an important part of keeping the reproductive system healthy. The vagina is a self-cleansing organ.

•You should also perform a breast self-examination once a month.

Problems of the Female Reproductive System•Some of the problems that occur are related to menstruation. Others are related to infertility, the inability of a woman to become pregnant.

Problems Related to Menstruation

Menstrual Cramps

Premenstrual Syndrome

Toxic Shock Syndrome

Problems that Can Cause Infertility

Blocked Fallopian Tube

Endometriosis

Pelvic Inflammatory Disease

Other Reproductive Disorders

Some other disorders include ovarian cysts and cancers of the reproductive system. About one out of every eight females develop cancer at sometime. Early sexual activity, as well as family history of cervical cancer and other

factors, is related to an increased incidence of cervical cancer. A Pap test should be done every one or two years after a woman has reached 18 years of age or has become sexually active.