Animal tissue, Disease, Developmental Biology and Biotechnology Notes

ANIMAL TISSUES

● Study of tissue→ Histology

● 'Histology' word coined by→Mayer

●'Tissue' introduced by→ Bichat

● Father of Histology→ Bichat

● Father of Microscopic Anatomy→ Marcello Malpighi

Tissues:

● Epithelial tissue:

                         → Only tissue with basement membrane.

● Squamous tissue:

→ Alveoli of Lungs, Blood vessels, Bowman's capsule, Capillaries, Pleura,        Pericardial, and Peritoneal.

● Cuboidal tissue:

→ Salivary gland, Pancreas, Collecting duct of kidney (seminiferous tubule), germinal epithelium of ovary, Lens, Choroid plexus, retinal Layer.

● Non-ciliated columnar tissue:

                        → Lining of stomach, Large intestine, Uterus.

● Ciliated columnar:

                        → Ventricle of brain, oviduct, Trachea, Efferent ductules of testis.

● Pseudo- stratified columnar tissue:

                        → Tracheal lining, Bronchi, Eustachian tube, Nasal cavity, vas deferens.

● Stratified squamous tissue:

- Non-keratinized→ Vagina, Conjunctiva, Anal Canal, Cervix, Pharynx.

- Keratinized→ Skin, Hair, Nail.

● Stratified Cuboidal tissue:

                        → Lining of duct of salivary gland, Sweat gland, developing graffian follicle.

● Transitional Epithelium tissue:

                        → Lining of Ureter, Urinary Bladder, Urethra, Renal Pelvis (@3UP)

● Connective Tissue:

            ►Proper Connective Tissue:

                        → Loose Connective Tissue (Areolar)

                        →Adipose Tissue

                        → Fibrous Tissue/dense connective tissue

                        → Reticular Connective Tissue

            ► Supporting Tissue:

                        → Bone

                        →Cartilage

            ► Fluid Connective Tissue:

                        → Blood

                        → Lymph

# Loose connective tissue/ Areolar tissue contain fibroblast, mast cell, histocyte, lymphocyte, plasma cell.

◘ Fibroblast synthesize (collagen, elastin, and reticulin)

◘ Mast cells are 'modified basophils of blood'.

◘ Heparin (anticoagulant), histamine (vasodilator), and serotonin (vasoconstrictor).

◘ Histocyte are phagocytic cells derived from monocyte.

◘ Plasma cells (cart wheel cells) produce antibodies and are active B-lymphocyte.

 # Adipose Tissue:

► Fibroblast are modified for fat storage,

► Fat cells with small fat droplet is brown adipocyte whereas cells with large fat lobule is called as white adipocyte.

► They are also loose connective tissue. Prominent adipose sites are Hump of camel, Blubber of Whales, Subcutaneous fat, etc.

# Fibrous tissue/ dense connective tissue:

• Composed of bundles of collagen fibres and found in the joints of bones.

◘ Tendon→  Non- elastic, white collagen fibre.

                → Connect bone to muscle.

                → Rupture causes strain.

◘ Ligament→  Elastic, yellow elastin fibre.

                   → Connects bone to bone. (@BoBli)

                   → Rupture causes sprain.

◘ Reticular Tissue → Modified areolar, connective tissue that lacks collagen and elastic fibres.

                                → Protect body from wound and infection.

                               → Form framework or stroma of lymphatic organs.

►Supporting tissue (Mesodermal origin):

◘ Cartilage→ Covered by perichondrium.

Types of cells:

                  → Chondroblast

                  → Chondrocyte

                  → Chondroclast

Blast= Forming, Cyte= Mature & Clast= Merophages

• Hyaline cartilage→ Most abundant.

   →Found upon articular surfaces at joins of long bones.

• Elastic cartilage→ Found in the wall of Larynx, ear pinna, epiglottis and Eustachian tube.
• Fibro-cartilage→ Strongest cartilage.

 → Occurs in joints between vertebrae (inter-vertebral disc) and also in pubic symphysis.

            ◘ Bone→ Strong connective tissue.

                        → Matrix contains ossein[ Ca₁₀(PO₄)(OH)₂]

Cells:   → Osteoblast

            → Osteocyte

            → Osteoclast

• Ossein deposited in concentric rings called lamellae between periosteum and endosteum.
• Between adjacent lamellae are numerous small cavities called lacunae which gives off numerous fine branching tubules called Canaliculi.
• Osteon or Haversian system present in mammalian bone.   
• Volkman's canal connect different haversians systems.
• Diaphysis- Long main portion.
• Epiphysis- Ends of bone.
• Central cavity contains yellow marrow in the shaft and red marrow at the ends.
• Paget's disease is characterized by irregular thickening and softening of bones resulting in deformation.

# Fluid Connective Tissue:

● Blood→ p^H= 7.35-7.45

● p^H of blood in arteries is more than in veins.

● Composition→ Plasma

                        → Blood cell:

• Erythrocyte (RBC)Leucocyte (WBC)Thrombocyte (Platelets)

● RBC→ RBC count in male= 5 million/ mm³

                                  in female= 4.5 million/ mm³

● Abnormal increase in RBC→ Polycythemia

● Sickle-cell anaemia is a genetic disease and is due to change is Beta-cell of haemoglobin.

● Thalassemia is a hereditary anaemia due to the defect in synthesis of anaemia.

● Large amount of reduced haemoglobin in arterial blood result in condition called cyanosis.

Anaemia:

● Microlytic→  Deficiency of iron.

● Megalobastic→ Deficiency of folic acid and vitamin B12.

● Pernicious→ Deficiency of Vitamin B12.

● Haemorrhage→ Excessive bleeding.

● Haemolytic→ Rupture of RBC

● Aplastic→ Destruction of bone marrow

● WBC→ 500/mm³ of blood

●  Group→ Agranulocyte

                        - Lymphocyte

                        - Monocyte

               → Granulocyte       

- Neutrophil

- Eosinophil

- Basophil

●  Lymph differs from blood in having no RBC.

# Muscular tissue:

◘ Cardiac muscle → Striated and involuntary.

◘ Skeletal muscle→ Striated and voluntary.

◘ Visceral muscle→ Non-striated and voluntary.

● Skeletal muscle fibre shows transverse striations in the form of regular alternate dark A and light I bands.

● At centre of I band is a fine, dense Z-line or Krause's membrane.

● Z-line or Krause's membrane divides myofibrils into functional units called Sarcomeres.

● Sarcomere is an area between two Z-lines.

● Lactic acid is converted to glycogen through Cori's cycle in liver.

# Nervous tissue:

→ Neuroglia

→ Neuron

◘ Neuroglial cell ( Non-neuronal cells):

            ► Astrocyte→ Form blood brain barrier.

            ►Oligodendrocyte→ Myelination in CNS.

            ► Schwann cell→ Myelination in PNS.

            ► Microglia→ Macrrophages in brain.

            ► Ependyma cell→ Form internal lining of ventricles.

◘ Neuron:

            ● Longest cells in human body.

            ● Nerve cells donot divide.

            ● Portion→ Cell Body

                           → Dendrites

                           → Axon

► Cell body or cyton/ perikaryon/ Nissls bodies or trigoid granules→ Rich in RNA and concerned with protein synthesis.

► Dendrites→ Receives impulse.

► Axon→ Transmits impulse.

            → Nissl bodies absent in axon.

◘ Types of Axon:

                        → Myelinated

                        → Unmyelinated

● Myelinated or medullated or white fibre is surrounded by a phospholipid covering called myelin sheath.

● Myelin sheath produced by Schwann cells.

● Unmyelinated gaps or constrictions in axons are called Nodes of Ranvier.

◘ Types of neurons:

            ► Unpolar→ Found in Hydra.

            ► Unipolar→ Found in dorsal root ganglia and neurons of vertebrate embryo.

            ► Bipolar→ Found in retina of eyes, olfactory epithelium and inner ear.

            ► Multipolar→ Found in brain and spinal cord.

HUMAN DISEASES

Incubation period- Time interval between entry of pathogen an appearance of first symptom.

Tuberculosis (Koch’s disease)

Mycobacterium tuberculosis(Pulmonary TB)

Mycobacterium bovis(abdominal TB)

Symptom-

Fever, Hemoptysis( Blood in sputum), night sweat, cough

Diagnosis-

Zeihl neel(ZN) stain, Montoux test, sputum test, PCR

Ghon focus- White foci seen during chest X-ray

Treatment-

@PRISE

Pyrazinamide – side effect{kidney, liver, ear}

Rifampicin- side effect{liver-red colour}

Isoniazide- side effect {peripheral neuritis}

Streptomycin – only injectable

Ethambutol – only non-bacterial (cause ocular toxicity in child)

DOTS- Directly Observed Treatment Short Course

World TB day- 24^th march

Saarc tuberculosis centre located in Bhaktapur, Nepal

Incubation Period- 3 weeks to 3 months

Diarrhoea

Most common cause of diarrhea in adult is due to giardiasis but in child is due to rota virus.

Giardia lamblia(Grand oldman of intestine)

Habitat –

Duodenum, Upper Jejunum

Incubation- 3 weeks

Infective (quadrinucleated) cyst and feeding tropozoite(binucleated).

Symptom-

Diarrhoea, Abdominal Pain, fatty stool, foul smell

Treatment-

Tinidazole, Metronidazole, Secnidazole

Ascaris lumbricoides

Habitat- Lumen of small intestine

Incubation- 1 to 2 months

Treatment- @MAP (Mebendazole, Albendazole, Piperazine)

AIDS

High risk of transmit in homosexual contact and most common in heterosexual contact.

Transmittance through blood has risk more than 90%

Diagnosis

1. ELISA or screening test
2. Western blot test or diagnostic test

Treatment

Ziduvudine, Lamivudine, Nevirapine, Squinavir

Lamivudine also used in Hepatitis B.

World AIDS day observed on 1^st December.

Typhoid

Agent- Salmonella typhi

Habitat-

Small intestine (ileum)

[gall bladder in chronic carrier]

Symptom-

Step ladder pattern fever, GI symptoms, Neutropenia, Bradycardia, Splenomegaly, Hepatomegaly

Diagnosis-

@BASU

Blood culture, Antibody antigen reaction(Widal test), Stool test, Urine test(Each test in every week one after another)

Treatment

Chloramphenicol, Ciprofloxacin, Ceftriaxone, Amoxicillin

Cancer

Oncology-Study of cancer

Carcinogen- Cancer causing agent

Benign- suffix oma

Malignant- suffix sarcoma and carcinoma

Most common cancer in children is Acute Leukemic Leukemia(ALL).

Diagnosis-

Biopsy, Imaging

Treatment-

Surgery. Cisplatin and vinscristin are chemotheraphy.

PAP smear test is used in detection of cervical cancer.

Mammogram- Test for breast cancer.

Drugs

Narcotic- Heroine, Codeine, Ephedrine, Morphine

Stimulants- Ampletamine, Cocaine, Caeffein

Tranquilizer-

Sedative- Barbiturates, Alcohol

Hypnotic- Hasis, Marijuana, Chares

Hallucinogens- LCD from claviceps pupurea), Mescaline from cactus, Psilolybin from mushroom, Bhang, Ganja, Chares

Opium obtained from Papaver sominiferous.

Alcohol

Causes fatty liver syndrome and cirrhosis of liver

Alcoholic becomes deficient in vit. Bcomplex(thiamine) which cause Korsakoff psychosis and Wernicke’s encephalopathy.

Antitobacco day- May 31.

Tobacco contains CO, aromatic hydrocarbon, Nicotine, Tar

Most commonly abused substance in Nepal is Tobacco and in the world is alcohol.

Typhoid affects- Payer’s of patches of Illeum.

Adenoma is cancer of glands.

HIV infects CD4+ T Helper celles.

Tissue	Macophages
CNS	Microglia
Lungs	Dust cell
Liver	Kupfer cell
Lymph nodes	Histocytes
Spleen	Sinusodial cell
Skin	Langerhan’s cell
Kidney	Mesangial cell
Bone	Osteoclasts
Thymus	Hassals corpuscles

DEVELOPMENTAL BIOLOGY

Eqq quanity of yolk

• Alecithal(Human)
• Microlecithal(starfish, Rabbit)
• Mesolecihal(Amphibian, lung fish)
• Macrolecithal(Arthopd, fish, reptile, bird)

Position of Egg

• Isolecithal
• Telolecithal (frog, reptile, bird)
• Centrolecithal (Arthropods)

Cleavage in frog is holoblastic but unequal.

Cleavage------------>Morulla------------>Blastula------------>Gastrula

Blastocoel present in Blastula and Archenteron present in Gastrula.

Blastopore form future anus.

Blatopore present in gastrula.

Achenteron present in lumen of future gut.

Mammalian cleavage is holoblastic and equal.

Developed from

Ectoderm (@4 EPIC)

• Epidermis,
• Eye(Lens, Conjunctiva, Retina),
• Enamel,
• Entire Nervous system except mennings and microglia,
• Pituitary and Pineal gland
• Internal ear
• Cornea

Mesoderm (@MESCODERM)

• Muscular
• Excretory
• Skeletal, sclera, Spleen
• Connective tissue, Coelomic epithelium, Choroid
• Dentine, Dermis
• Reproductive
• Male gonads, Myocardium of heart

Endoderm (@REaDY THYO)

• Respiratory
• Eustachian
• Digestive
• Thyroid, parathyoroid, thymus

Adrenal medulla developed from ectoderm.

Gestation period of human is 280 days and rabbit is 28 to 32 days.

Metamorphosis in frog is regulated by thyroxin.

If unfertilized ovum of frog is prickled with micro-needle it will start dividing.

BIOTECHNOLOGY

Biotechnology was coined by Ereky.

Tissue culture is based on the concept of totipotency.

Vectors in genetic engineering are mainly plasmid, cosmid, bacteriophage.

Eugenics- Improvement of human gene.

Euthenics -  Environmental  manipulation of suitable genotypes to produce improved species.

Euphenics – Making biological improvement in humans after birth.

Enology is study of production of wire.

Saccharomyces cervisiae – yeast (Fermentation is exothermic process)

Fleming discovered penicillin from fungus Penicillum notatum but it is commercially produced from penicillium  chrysogenum.

Waksman discovered streptomycin and also coined the term antibiotics.

Narrowed discovered antibiotics [ @VESPa]

Vancomycin, Erythromycin, Streptomycin, Penicillin

If barr body present in foetus then female if absent male.

Common manure in Nepal- Sesbania

Board spectrum antibiotics

Chloraphenicol , Rifampicin, Terramycin, Kanamycin

Tissue Transplant

A) Autograft

- One’s own tissue grafted to another part of the body.

B) Isograft

- Genetically identical donor and recepient .

C) Allograft

- Transplant between individuals of same species.

D) Xenograft

-Transplant between members of different species.

Banting and Best isolated insulin from pancreas of dog and demonstrated its effectiveness against diabetes.

World’s first test tube baby is Louise Joy Brown and first test tube baby of Nepal is Om Mani Tamang.

	Generic Name	Deficiency causes
Vitamin A	Retinol	Night blindness, Xerophthalmia
Vitamin D	Calciferol	Rickets (Children), Osteomalacia
Vitamin E	Tonopherol	Reversed sterility in rats
Vitamin K	Phylloquinone	Haemorrhage, Scurby

	Name	Deficiency symptom
Vitamin C	Ascorbic acid	Scurby
Vitamin B1	Thiamine	Beri-beri
Vitamin B2	Riboflavin	cheilosis, glossitis
Vitamin B4	Pyridoxine	Pellagra
Vitamin B12	Cyanocobalamine	Pernicious Anemia
Protein		Kwaswokor
Protein and food calorie		Marasmus

Credit- Praful Basnet