BIOCHEMISTRY CHEMISTRY OF LIFE

2. BIOCHEMISTRYCHEMISTRY OF LIFE

3. BIOCHEMISTRY The science concerned with the chemical basis of life, it deals with chemical structure and chemical changes or metabolic processes which take place in the tissue cells. It is a science concerned with the chemical constituents of living cells and the reaction and process they under go As long as these reactions take place in organized form, we remain healthy and alive, as disorganization occur in these reactions we fall ill or even die.

4. AIM OF BIOCHEMISTRY Is to describe and explain in molecular and chemical terms the structure and all chemical processes of living cells. To achieve the aim of biochemistry , the biochemists study the structure of cells at molecular level and analyse their functions.

5. ROLE, IMPORTANCE AND ESSENTIALITY OF BIOCHEMISTRY • Biochemistry is quite young but due to rapid and expending studies and researches in biochemistry it become the most dynamic science ,lot of medical sciences depend upon its studies and researches i e • Medicine • Pharmacology • Bacteriology • Pathology • Therapeutic • Biochemical investigation • The biochemists has provided vitamins, hormones, prepare vaccines, antibiotic, antitoxins, serum, enzyme inhibitors, DNA technology, genetic engineering and gene mapping have opened a new era in medicine.

6. ROLE, IMPORTANCE AND ESSENTIALITY OF BIOCHEMISTRY • Biochemistry is essential to understand normal chemistry , metabolism, function and growth of normal human body and to find out the aberrant biochemistry of human body in various diseases and clinical conditions.

7. Branches of Biochemistry • Human biochemistry • Clinical biochemistry • Plant biochemistry • Nutrition biochemistry • Industrial biochemistry • Animal biochemistry • etc

8. Human biochemistry • Cell structure and function • Biochemistry of all chemical reaction of our body • Biochemical composition • Immune system and its function • Nutrition, mineral, metabolism and vits • Tissue metabolism • Molecular biology and genetics • etc

9. Clinical/Medical Biochemistry • The normal biochemistry of healthy human body and the altered or damaged biochemistry and there study diagnosis and treatment.

10. Cellular Biochemistry: Cell Structure & Function

11. CHEMISTRY OF HUMAN CELL • The 90% 0f dry weight of human cell is composed of carbon ,hydrogen, oxygen, nitrogen, phosphorus and sulfur. • Several other functionally important elements are also found in cells. These include Ca, K, Na, Cl, Mg, Fe, Cu, Co, I, Zn, F, Mo and Se.

12. Cell structure and function • The structural and functional unit of life. • Two types prokaryotic and eukaryotic cells. • The cell is a COMPLEX CHEMICAL FACTORY.

13. cell • Cell membrane cytoplasm nucleus • Cytosol cell organelles Non membranous organelles membrane bound organelles Ribosomes Centrosomes single membraned double membrane Basal bodies golgi bodies, ER , mitochondia Microfilaments Lysosomes, Peroxisomes

14. Molecular Organization of a cell

15. Eukaryote Cell

16. Nucleus(control centre of the cell) Double membrane surrounding the chromosomes and the nucleolus. Pores allow specific communication with the cytoplasm. The nucleolus is a site for synthesis of RNA making up the ribosome. • Nuclear envelope • Nuclear pore complexes • Chromatin • Nucleolus • Nucleoplasm

17. Nucleus • The nucleus is separated from the cytoplasm by the nuclear envelope

18. Nuclear envelope: membrane surrounding the nucleus Nuclear pores: open portals of communication between the nucleus & cytoplasm Chromatin: condensed DNA Chromosome: very tightly packed DNA Nucleolus: dense region of chromatin Nucleus: DNA stored here.The Control Center

19. Nucleolus (Nucleoli) • The RNA of ribosomes is synthesized from genes in the nucleolus • No membranes separate nucleoli from the surrounding chromatin in the nucleus

20. Functions of nucleus • Chromosomes present in the nucleus which serve to store, express and transfer the genetic in formation from one to other generation. • Nucleolus the factor of RNA synthesis. • DNA replication takes place in the nucleus during cell division. • Hormonal receptor are present in nucleus.

21. Biomedical significance of nucleus • Karyoplasmic index constant the ratio b/w nucleus and cytoplamic volume is proportional but in malignant tumours cells nucleus are irregular in shape and large in size. • Mutation of DNA gene due to carcinogenic agents cause Ca, leukaemia, lymphomas etc.

22. Anatomy of eukaryotic cell Mitochondria (power house of cell)

23. Mitochondria (power house of cell)

24. Mitochondria • Shape variable from rod-shape to spherical. • Size 1.0- 10 um in length to 0.2- 0.8um in width. • Numbers 500-800 upto 2500/cell. • Occurrence uniformly distributed in cytoplasm.

25. Mitochondria • The mitochondria major role is ATP production in the eukaryotic cell • These are mobile and flexible organelles, • although in some cells they tend to stay in a fixed position • Mitochondria are also self-reproducing, they have their own circular DNA

26. Mitochondrial structure • Two membranes • Inner membrane invaginated • Numbers of mitochondria per cell vary but usually 100s/cell Matrix contains the TCA cycle (and other) soluble enzymes Outer membrane contains PL, CH and protein (porin) Inner membrane contains metabolite transporters and the electron transport chain

27. Four large, multi-subunit protein complexes - complex I is a NADH-ubiquinone reductase - complex II is succinate dehydrogenase (part of the TCA cycle) - complex III is the ubiquinone -cytochrome c reductase - complex IV is cytochrome oxidase The respiratory electron transport chain

28. Mitochondrial inheritance. Sperm mitochondria are shed before entry of the sperm nucleus. All mitochondrial in the zygote are contributed by the egg cell

29. Biomedical significance of mitochondria • Megamitrochondria in hepatic and alcoholic liver diseases • Mitochondrial myopathies. • Mitochondrial dysfunctions. • Genetic disorders like Leigh syndrome, Hepatopathy , ketoacidosis, Cardiomyopathy, encephalopathy, Leukodystrophy, renal tubulopathy, Hypertrophic cardiomyopathy, Encephalopathy, liver failure, renal tubulopathy and Encephalopathy.

30. Endoplasmic reticulum • Rough endoplasmic reticulum • smooth endoplasmic reticulum • Are connected and are continuous with the nuclear envelope • Involved in protein synthesis, transport, modification , storage and secretion.

32. Rough endoplasmic reticulum • It is rough because imbedded in the membrane are ribosomes the site of the synthesis of secretory proteins. • The rough ER is also the site for the synthesis of membrane • Enzymes synthesize phospholipid that forms all the membranes of the cell. • Ribosomes in the rough ER synthesize protein that then are converted to glycoprotein and packaged in transport vesicles for secretion.

35. Smooth endoplasmic reticulum • The smooth ER is the site for the synthesis of lipids, phospholipids, and steriods • Note that the production of steriod hormones is specific tissue for example, it is the smooth ER of the cells of the ovaries and testes that synthesize the sex hormones.

36. Smooth endoplasmic reticulum • Enzymes in the smooth ER regulate the release of sugar into the bloodstream. • Other enzymes break down toxic chemicals. • As the liver is exposed to additional doses of a drug the liver increases the amount of smooth ER to handle it. • It then takes more drug to get past the detoxifiyingability of the liver • The smooth ER functions to store calcium ions. • In lipid synthesis.

38. Golgi apparatus • The Golgi apparatus, like the ER, is a series of folded membranes • It functions in processing enzymes and other products of the ER to a finished product • It is the source of the production of lysosomes • Receives proteins & lipids in membrane-bound vesicles from ER • Modifies those proteins & lipids • Sorts and ships the proteins & lipids away in membrane-bound vesicles

40. vesicles from ER vesicles leaving Golgi complex Golgi complex

41. Lysosomes • These are membrane bound vesicles that harbor digestive enzymes about 30-40. • The membrane of a lysosome will fuse with the membrane of vacuoles releases these digestive enzymes to the interior of the vacuole to digest the material inside the vacuole. • Have specific PH 5

42. Gout and Rheumatoid Arthritis • Gout is deposition of uric acid crystals of the joints often from over consumption of meat. • Other Rheumatoid factor complexes in the leucocytes (white cells) of the joints. • These rupturelysosome torelease enzymes that degrade the components of the synovial membrane in the joints, causing great pain and joint deformation. • Tay-Sachs Disease

44. Vacuoles • These are membrane-bound sacs that have many different functions. • It may also function in absorbing water. • The central vacuoles of flower petal cells may hold the pigments that give the flower its color

45. 0.5 micrometers 0.5 micrometers Ribosomes • Ribosomes assemble amino acid monomers into polypeptide chains • Associated with the ER • Composed of RNA and proteins

46. Ribosome Assembly/Structure • If individual proteins and rRNAs are mixed, functional ribosomes will assemble • Cytoplasmic ribosomes are larger and more complex, but many of the structural and functional properties are similar

47. Mechanics of protein synthesis • All protein synthesis involves three phases: initiation, elongation, termination • Initiation involves binding of mRNA and initiator aminoacyl-tRNA to a small subunit, followed by binding of a large subunit • Elongation: synthesis of all peptide bonds - with tRNAs bound to acceptor (A) and peptidyl (P) sites • Termination occurs when "stop codon" reached

48. Mechanics of protein synthesis • All protein synthesis involves three phases: initiation, elongation, termination • Initiation involves binding of mRNA and initiator aminoacyl-tRNA to a small subunit, followed by binding of a large subunit • Elongation: synthesis of all peptide bonds - with tRNAs bound to acceptor (A) and peptidyl (P) sites • Termination occurs when "stop codon" reached

49. Peroxisomes or Microbodies • Produce and degrade hydrogen peroxide, a toxic compound that can be produced during metabolism. • Beta oxidation of long chain fatty acids . • It is absent in Inherited disorder Zellweger,s syndrome.

50. Peroxisomes or Microbodies • For oxidation of fatty acids and toxicants, it contains oxidative enzymes. • E.g. catalase in peroxisomes can decompose hydrogen peroxide into water. • Abundant in hepatocytes (liver cells), where oxidation of fatty acids (and other organic matters) takes place and produces hydrogen peroxide. • Life span is short and the numbers of peroxisome vary. • They replicate like mitochondria, and they are not budded from Golgi. The enzymes are sent and deposited into the peroxisomes.