Introduction of Biochemistry for B.Sc. Nursing

2. Unit 1
Introduction

3. Biochemistry
• Bio-chemistry is the study of chemical substances and vital
processes occurring in living organisms . It includes the study of
chemistry behind biological processes and the synthesis of
biologically active molecules.
• Biochemistry is the application of chemistry to the study of
biological processes at the cellular and molecular level.
• It emerged as a distinct discipline around the beginning of the
20th century when scientists combined chemistry, physiology
and biology to investigate the chemistry of living systems by:

4. Biochemistry
a) Studying the structure and behavior of the complex molecules
found in biological material and
b) The ways these molecules interact to form cells, tissues and
whole organism
 The name Biochemistry was coined in 1903 by a German
chemist named Carl Alexander Neuber (1877-1956).
 The study of biochemistry involves enzymes, nucleic acids,
carbohydrates, sugars, proteins, and lipids.

5. Definition and significance in nursing
• Nursing encompasses autonomous and collaborative care of
individual of all ages, families, group and communities, sick
or well and in all settings.
• Nursing includes the promotion of health, prevention of
illness, and the care of ill, disabled and dying people.
• Advocacy, promotion of safe environment, research,
participation in shaping health policy and in patient and
health systems management, and education area also key role
of nursing.

6. Significance in nursing
• Biochemistry involves the chemical processes that occur in
all living cells and organism.
• It is crucial to nurses in understanding how the human body
functions in both normal and various disease states.
• The Krebs cycle, for example, is a multi-step biochemical
process by which the human body (and many other living
organism) produces energy as a part of aerobic metabolism.
• If BSN programs omitted key fundamentals like this, nurses
would have no understanding of how such common things as
acute and critical illness, trauma, surgery, cardiac arrest,
fever, infection, hyperglycemia, or starvation, for example,
affected their patients.

7. Significance in nursing
• Nursing interventions are based on this understanding. In
critical care, for instance, nurses learn how to preserve patients'
energy by spreading cares throughout the day and night.
• How medications work is directly related to biochemistry.
• Antibiotics, for example, work on the various microorganisms
differently. Some antibiotics kill bacteria outright, by making
holes in their cell walls. Others keep bacteria from replicating
by disrupting intracellular processes.
• Nurses work as part of patient care teams and closely with
families.

8. Significance in nursing
• Biochemistry is significant to the profession of nursing
because the vast majority of nurses' patients are human.
• Humans are biological organisms living in a rich soup of
chemical interactions. Biochemistry is that narrow discipline
of chemistry concerned with the processes occurring in living
organisms.
• Basically, a nurse should have some understanding of the
mechanisms that might support interventions to help their
patients feel better and some insight as to the sort of problems
that make them feel worse.

9. Significance in nursing
• If an infants is always vomiting after giving milk ,she or he
probably has galactose intolerance.
• If an infant is born with jaundice, her or his liver is not fully
functional.
• When color of infants urine turns dark ,probably he/she
suffers from an amino acid metabolic disorder.
• Many such condition thus, can be explained on the basis of
bio-chemistry.

13. Cells
• Basic building blocks of life
• Smallest living unit of an organism
• Grow, reproduce, use energy, adapt,
respond to their environment
• Many cannot be seen with the naked
eye
• A cell may be an entire organism or it
may be one of billions of
• cells that make up the organism

14. Cells maybe prokaryotic or eukaryotic
• Prokaryotes include bacteria & lack a nucleus or membrane-
bound structures called organelles
• Eukaryotes include most other cells & have a nucleus and
membrane-bound organelles (plants, fungi, & animals)

25. Cell membrane/Plasma membrane
• Every cell in the body is enclosed by a cell plasma membrane.
• The cell membrane separates the material outside the cell,
• It maintains the integrity of a cell and controls passage of
materials into and out of the cell.
• All materials within a cell must have access to the cell
membrane (the cell's boundary) for the needed exchange .
• The membrane is composed of phospholipid molecules
arranged in a bilayer.
• Embedded in the membrane are proteins.

26. Cell membrane/Plasma membrane
• The cell membrane keeps the cell together by containing the
organelles within it.
• Cell membranes are selectively-permeable, allowing materials
to move both into and outside of the cell.
• Active and passive transport systems; act as a receptor sites and
functions as a carrier molecules, and provides identification
markers.

28. Nucleus
• Found in all eukaryotic cells except in mature phloem sieve
tube elements and mature red blood cells of mammals.
• Almost all cells are mono- nucleate, but bi-nucleate cells (some
liver and cartilage cells) and poly-nucleate cells (some white
blood cells) also exits.
• It is bounded by a double membrane (nuclear envelope).
• The envelope possesses many large pores which permit the
passage of large molecules, such as RNA.
• The cytoplasm- like material within the nucleus is called
nucleoplasm.

29. Nucleus
• It contains chromatin which is made up of coils of DNA bound
to proteins.
• Act as a control center for the activities of a cell
• The nuclear DNA carries the instructions for the synthesis of
proteins
• It is involved in the production of ribosomes and RNA
• It is essential for cell division

30. Nucleolus
• Appears as a rounded, darkly stained structure inside the nucleus.
• One or more nucleoli may be present in a cell.
• It stains intensely because of the large amounts of DNA and RNA
it contains.
• During nuclear division nucleoli seem to disappear, but this is
because the DNA
• disperses. They reassemble after nuclear division.
• making ribosomes

32. Cytoplasm
• Cytoplasm is a jelly-like substance that is sometimes described
as "the cell-matrix".
• It is the medium for chemical reaction.
• It holds the organelles in place within the cell.
• All of the functions for cell expansion, growth and replication
are carried out in the cytoplasm of a cell.
• Within the cytoplasm, materials move by diffusion, a physical
process that can work only for short distances.
• Site for Glycolysis and most of gluconeogenesis; Pentose
Phosphate shunt; Fatty acid biosynthesis.

34. Ribosomes
• It is a small (20nm in diameter) and non-membranous structure
• It consists of two subunits, one large (called 70S) and one
small ( called 80S)
• These are responsible for the processing of genetic instruction
carried by mRNA.
• Some of the ribosome float free in the cytoplasm, called free
ribosome while others are bound to endoplasmic reticulum.
• it acts as a binding site for protein synthesis

37. Mitochondria
• "Mitochondria" is a plural term; which is appropriate as these
are not found alone. The quantity of mitochondria within cells
varies with the type of cell.
• These are power generator and self-replicating organelles.
• Both the organelles are surrounded by a double membrane with
an intermembrane space.
• Many folding, filling their inner space. they have two
functionally distinct membrane systems, inward folds are
called cristae.

38. Mitochondria
• These are the energy producers within the cell.
• They generate energy in the form of Adenosine Tri-Phosphate
(ATP).
• Site for Krebs Cycle; Electron transport system and Oxidative
Phosphorylation; Fatty acid oxidation; Amino acid catabolism;
Interconversion of carbon skeletons.

40. Plastid
• Semi-autonomous organelles having DNA and double
membrane envelope which store or synthesis various types of
organic compounds
• It develops from colorless precursors called protoplastids
• Depending upon their color, they ae of three main types;
• Leucoplasts (Amyloplasts, Elaioplasts and Aleuroplasts)/(Leucos)
• Chromoplasts (Chroma)
• Chloroplasts (Chloros)

42. Endoplasmic reticulum
• ER is the transport network for molecules.
• It is present in two forms called
• Rough endoplasmic reticulum (RER) and
• smooth endoplasmic reticulum (SER) .
• "Rough" indicates that there are ribosomes attached to the
surfaces of the endoplasmic reticulum.
• The endoplasmic reticulum is the site for membrane and
secretary protein biosynthesis.
• Site of phospholipid biosynthesis and detoxification reactions
takes place.

45. Golgi apparatus
• It is a cup- shaped organelle located near the nucleus in many
types of cells.
• The apparatus consists of a set of smooth cisternae, which
close fluid filled flattened membranous sacs or vesicles.
• Contains a series of five to eight membrane covered stacks
called cisternae
• Animal cells generally contain between ten and twenty Golgi
stacks which are linked to a single complex by tubular
connections between cisternae

46. Golgi apparatus
• Their main function is to process the immature enzymes into functional
enzymes and to release them in a closed vesicle.
• Golgi complex participates in cell wall information, i.e. cell plate,
primary and secondary wall formation.
• They are also concerned with giving rise to primary lysosome.
• They are believed to play a role in regulation of fluid balance.
• Golgi complex is supposed to play a role in phospholipid synthesis, lipid
absorption etc.
• The packaging of secretory materials, example- mucin, enzyme, milk
lactoprotein, melanin pigment etc., which are to be discharged from the
cell.

48. Lysosome
• These contain hydrolytic enzymes and as a matter of fact these
are the lytic bodies functioning as suicidal bags.
• It has a high acidic medium of pH 5.0 and this acidification
depends on ATP- dependent proton pumps.
• Intracellular digestion- Lysosomes are responsible for the
digestion of particulars that are taken into the cell by
phagocytosis.
• Autophagy- During adverse conditions, lysosomes begin to
digest its own cell inclusions such as mitochondria and ER.
This is called cellular autophagy.

49. Lysosome
• Aging- Lysosomes are considered as agents of aging, for they
produce autolytic that slowly disrupt the intracellular
machinery.
• Autolysis- They perform the function of removing the dead or
degenerating cells and this process is known as autolysis.
• Cell division- Lysosomes may be involved in repressing
mitotic division of a cell.

51. Cytoskeletal structures
• They are extremely minute, fibrous and tubular structures
which form the structural framework inside the cell
• Occur only in eukaryotic cells
• Maintains shape of the cell and its extensions, regulates
orientation and distribution of the cell organelles
• Three types;
• Microfilaments,
• Intermideate filaments and
• Microtubules

53. Cytoskeletal structures
• Microfilaments:
• Ultramicroscopic, long, narrow cylindrical rods or protein filaments which
occur in eukaryotic plant and animal cells
• Connected with spindle fibers, ER, chloroplasts, etc..
• Association with myosin protein
• Muscle fibers also represents it
• Intermediate filaments:
• Hollo filaments often form a network
• Four types: Keratin filament (tonofibrils and skin), Neuro filaments (lattice
with axon and dendrons of nerve cells), Glial filaments (astrocytes) and
Heterogenous filaments (muscles and connected to nuclear envelope and
centriole)

54. Microtubules
• Cylinders that contain 13 rows of protein called tubulin
• During cell division microtubules form spindle fibres, that
assist the movement of chromosomes
• They work as conveyer belts inside the cells
• They move vesicles, granules, organelles like mitochondria,
and chromosomes via special attachment proteins
• Microtubules may work alone, or join with other proteins to
form more complex structures
• Main constituent of the microtubule is a glycoprotein called
Tubulin; α-Tubulin and β-Tubulin.

56. Microvilli
• "Microvilli" is the plural form; "Microvillus" is the singular
form.
• Microvilli are finger-like projections on the outer-surface of the
cell.
• Not all cells have microvilli.
• Their function is to increase the surface area of the cell, which
is the area through which diffusion of materials both into, and
out of, the cell is possible.

58. Vacuoles
• It is a fluid-filled sac bounded by a single membrane (called tonoplast in
plant cell)
• It contains a solution of mineral salts, sugar, amino acids, wastes and
sometimes also
• pigments, these substance are collectively called ‘cell sap’
• Support and cell growth
• Store pigments
• As lysosome : sometimes it may contain hydrolytic enzymes, after cell
death the
• tonoplast losses its differential permeability and the enzymes escape
causing autolysis

59. Vacuoles
• Depending upon the contents and functions, vacuoles are of four types:
• Sap vacuoles (Fluid-filled, maintain cell shape, turgidity and water
absorption)
• Contractile vacuoles (Occurs in some protistan and algal cells, highly
extensible and collapsible membrane, osmoregulation and excretion)
• Food vacuoles (Protozoans protists, several lower animals and
phagocytes of higher animals, fusion of phagosome and lysosome, digest
material passed out into surrounding cytoplasm)
• Air vacuoles/pseudo vacuoles/gas vacuoles (prokaryotes, not only store
metabolic gases but also provide buoyancy, mechanical strength and
protection from harmful radiation)

62. Centrosomes
• The centrosomes contain the centrioles, which are responsible
for cell-division.

63. Biomolecules
• Just like cells are building blocks of tissues likewise molecules are
building blocks of cells
• Animal and plant cells contain approximately 10, 000 kinds of
molecules (bio-molecules)
• Water constitutes 50-95% of cells content by weight
• Ions like Na+, K+ and Ca+ may account for another 1%
• Almost all other kinds of bio-molecules are organic (C, H, N, O, P, S)
• Infinite variety of molecules contain C
• Most bio-molecules considered to be derived from hydrocarbons
• The chemical properties of organic bio-molecules are determined by
their functional groups. Most bio-molecules have more than one