PHYSIOLOGY of

HUMAN BODY SYSTEMS Unit 11

Grading criteriaP1 Identify tissue types from sections and/or photographs and be able to identify

abnormalities in the tissue.

M1 Explain how function is related to structure for the main systems in the body.

D1 Explain changes seen in the tissue owing to disease.

P1

• Identify tissue types from sections and/or photographs and be able to identify abnormalities in the tissue.

Differentiation of cells to form tissues

STRUCTURE in relation to FUNCTION

The 4 main classes of tissue are:

• epithelial

• connective

• muscle

• nervous

Epithelial: not clearly defined!

Glandular

Lining

Covering

• Sweat glands, goblet cells, gastric pits, etc.

• Inside arteries, veins, alveoli, etc.

• Skin, oesophagus, mucus membranes, etc.

Epithelial

• Glands Function = secretion.

LiningFunctions:• protection• secretion• mechanical

movement (ciliated)

• absorption• repair and

replacement of cells

Epithelial

Skin (covering)

Connective: functions are varied

• vascular• cartilage• bone• areolar• adipose• elastic• reticular (blood)• collagenous (tendons and ligaments)

Cartilage and bone

Fibrocartilage discs Bone: vertebrae

Muscle

skeletal

smooth

cardiac

Nerve tissues

• neurons • neuroglia (such as Schwann cells in the PNS)

Image shows a neuron and the small nuclei of neuroglia (supporting cells) in the CNS

Structure of a motor neuron

• The function of a motor neurone is to relay messages in the form of electrical impulses away from the CNS to the muscles or glands that receive the signals (effectors). The myelin sheath insulates the electrical impulse.

Nervous tissue inside the vertebra (CNS)

Histological section through nervous tissue

• A stained peripheral nerve fibre formed from many parallel nerves.

• The Schwann cells show up as dark rings because the myelin has been stained and the lipids in it stain dark.

Student activity• “Round Robin” : Using the microscopes

around the room (A – K) identify the tissue sections provided and put it in the correct class on your sheets! Briefly give the function of each tissue.

• skin, skeletal muscle, squamous epithelium (lung), smooth muscle, nervous, cartilage, ciliated columnar epithelium, cuboidal epithelium, bone, cardiac muscle, adipose tissue.

M1

• Explain how function is related to structure for the main systems in the body.

Activity: List the main body systems

List the 12 main body systems.In pairs – 1 minute!

Main Body SystemsBriefly identify the associated organs

1. Integument (skin).2. *Circulatory /*Cardiovascular 3. *Respiratory4. Digestive5. *Lymphatic6. *Immune7. *Urinary8. Nervous (Unit 12)

9. Endocrine (Unit 12)

10. Skeletal11. Muscular12. Reproductive (Unit 12)

Unit 12 The Physiology of Human Regulation and Reproduction

D1

Explain changes seen in the tissue owing to disease.

1. Cancer2. Heart disease3. Failure of ductus arteriosus or closure of the

foramen ovale after birth4. Diverticulitis: infected sac-like pouches in the

colon5. Osteogenesis imperfecta (Brittle Bone

Disease)6. Osteoporosis

1. Cancer• Cancer is a disease

of cells. The DNA in cells mutates and they cannot control cell division. The body is made up of a community of individual cells, each of which has a specific job to ensure that the community functions correctly.

Axillary node may develop into a breast cancer

Axillary node metastatic carcinoma

H & E stain Pan CK stain

Lung cancer

The spread of lung cancer…

Lung cancer Pathological findings in the dissection lab.

In the image on the left: the right lung appears normal. The left lung is pale in colour and is hard to the touch, indicating the presence of a lung tumour.

Below: Tumour surrounded by tar

2. Heart disease

What is coronary heart disease?

• Coronary heart disease is a disease of the heart caused by the accumulation of atheromatous plaques within the walls of the arteries that supply the heart muscle (myocardium).

• Angina pectoris and myocardial infarction (heart attack) are symptoms of and conditions caused by coronary heart disease.

Atherosclerotic plaque

Failure of ductus arteriosus closure after birth

• The ductus arteriosus usually closes at or shortly after birth. Once closed, blood can move from the heart directly to the lungs.

• If the ductus arteriosus remains open, flow reverses, and blood from the aorta is shunted left-to-right into the pulmonary artery and hence recirculated through the lungs.

Most cases occur as the result of a combination of genetic factors and environmental factors.

The combined factors lead to isolated defects in the elastic tissue.

• Normal Embryo • Patent Ductus Arteriosus

Normal heart circulation

Foramen ovale = “Hole in the heart”

• A hole in the heart is where there is an opening in the wall (septum) between the chambers of your heart. It may be between the two top chambers (atria) or between the two bottom chambers (ventricles).

Symptoms• Murmurs caused by defects in the heart do have

symptoms.

Those symptoms include:• shortness of breath • dizziness• chest pains• palpitations (a feeling that the heart is beating

faster or less regularly than normal)• congestion of the lungs.

Diverticulitis – infected sac-like pouches in the colon

• Diverticulitis is a common digestive disease particularly found in the large intestine.

• Diverticulitis develops from diverticulosis, which involves the formation of pouches (diverticula) on the outside of the colon.

Diverticulitis results if one of these diverticula becomes inflamed.

Osteogenesis imperfecta (Brittle Bone Disease)

X-ray of still born baby

• Osteogenesis imperfecta (abbreviated to OI and sometimes known as Brittle Bone Disease) is a genetic bone disorder.

• People with OI are born without the proper protein (collagen) or the ability to make it – usually because of a deficiency of Type 1 collagen.

• People with brittle bone disease either have less collagen than normal or the quality is poorer than normal.

• As collagen is an important protein in bone structure, this impairment causes those with the condition to have weak or fragile bones.

1 micrometre square Normal collagen Defective collagen

Osteoporosis: loss of bone mineral density

• Osteoporosis is a disease of bone – leading to an increased risk of fracture. In osteoporosis the bone mineral density (BMD) is reduced, bone microarchitecture is disrupted, and the amount and variety of non-collagenous proteins in bone is altered.

Grading criteriaP1 Identify tissue types from sections and/or photographs and be able to identify

abnormalities in the tissue.

M1 Explain how function is related to structure for the main systems in the body.

D1 Explain changes seen in the tissue owing to disease.