power point presentation on the topic cellular level of organization from unit first of subject human anatomy and physiology I for first year B.PHARM it is useful for the student to study easily and find out the material easily for their study it is also useful for techers

1. Miss .P. G.Kamble
Assistant Professor
M. Pharm (Pharmaceutics)
Gourishankar Institute of Pharmaceutical
Education and Research Limb,Satara

2. CELL
 Cell is the living, structural and functional unit of the body
enclosed membrane.
 There are about 200 different types of cells in our body .
 All cell arises from existing cell by the process of cell
division.
 In which one cell divided into two cells.
 Cell biology is the study of cellular structure of and
function,structure of cell intimately related to its function.

3. 1. Plasma membrane
2. Cytoplasm
a. Cytosol
b. Organelles
3. Nucleus

5.  The plasma membrane, or the cell
membrane, provides protection for a cell.
 It also provides a fixed environment inside the cell.
 And that membrane has several different functions.
 One is to transport nutrients into the cell and also to
transport toxic substances out of the cell.
 The plasma membrane functions as a physical barrier
between the external environment and the inner cell
organelles

6.  A Physical Barrier. ...
 Selective Permeability. ...
 Endocytosis and Exocytosis. ...
 Cell Signaling. ...
 Phospholipids. ...
 Proteins. ...
 Carbohydrates. ...
 Fluid Mosaic Model.

7.  The cytoplasm has two components:
a.Cytosol
The cytosol, by definition, is the fluid in which organelles of the
cell reside. This is often confused with cytoplasm, which is the
space between the nucleus and the plasma membrane. The
primary component of cytosol is water. Water makes up 70% of a
cell and is primarily in the cytosol to dissolve other components.
b.Organelles:
 Nucleus. Known as the cell's “command center,” the nucleus is a
large organelle that stores the cell's DNA (deoxyribonucleic acid).
...
 Ribosomes. Ribosomes are the protein factories of the cell. ...
 Endoplasmic reticulum. ...
 Golgi apparatus. ...
 Chloroplasts. ...
 Mitochondria.

8.  These are tiny granules composed of RNA &Protein.
 They synthesize protein from amino acids using RNA.
 When this is present in free units in the cytoplasm,the
ribosomes make proteins for use within the cell.
 Ribosomes are also found on the outer surface of the nuclear
envelope and rough endoplasmic recticulum where they
manufacture proteins for export from the cell.

9. It is the series of interconecting membranous canals in
the cytoplasm.
There are two types of endoplasmic reticulum
1.Smooth endoplasmic reticulum
 Here is lack of ribosomes.
2. Rough endoplasmic reticulum
 This is studded with ribosomes that synthesize proteins.

11.  It consist of stack of closely folded flattened
membranous sac.
 It present in all cells but is larger in those cells that
synthesize and export proteins.
 The proteins move from ER to golgi apparatus where
they are packaged into membrane bound vesical
called secretory granules.
 The vesicles are stored and when needed more to
plasma membrane, through which the proteins are
exported.

13.  Every cell in the body has nucleus,with exception of mature RBC.
 Skeletal muscle and some other cell contain several nuclei.
 It is larger organelle of the cell and is contained within nuclear envelope.
 The nucleus containing body’s genetic material which directs all metabolic
activities of the cell.
 This consist of 46 chromosomes, which are made from DNA.

14.  This is also called as ‘power
house of the cell’.
 They are involved in the
aerobic respiration. The
process by which chemical
energy made available in the
cell.
 This energy in the form of the
ATP which releases energy
when the cell break it down.
 Synthesis of ATP is most
efficient in the final stage of
aerobic respiration process
requiring oxygen.

15.  Motion of substances in and out of the cell.
 Cell membranes are selectively permeable.
 Two types of transport mechanism:
1. Passive transport
2. Active transport

16.  Passive transport is movement of molecules through
the membrane in which no energy is required from the
cell.
 Active transport requires energy expenditure by the
cell.

17.  Passive transport is movement of molecules through
the membrane in which no energy required from the
cell.
 Molecules move in response to a concentration
gradient.
- A concentration gradient is difference between the
concentration on one side of the membrane and that on
the another side.
- Passive transport mechanisms only movement
substances along the concentration gradient.

18.  Passive transport mechanisms only movement substance
along the concentration gradient.
 Substances move from an area of high concentration to an
area of low concentration.
 Mechanisms of passive transport:
1.Diffusion
movement of solute molecules from high solute
concentration to low solvent concentration.
2.Osmosis
Movement of solvent water from high solvent
concentration to low concentration.

19.  Diffusion is movement of solute molecules from high
concentration to low concentration.

20.  There are two types of diffusion
I. Simple Diffusion
II. Facilitated Diffusion

21.  Substance pass directly through the cell membrane.
 The cell membrane has limited permeability to small
polar molecules, water and ions.
 The motion of water across the cell membrane is
known as osmosis.
 The rate (molecules) of simple diffusion depends on
the degree of concentration gradient .
 At equilibrium, substances pass in out of the membrane
at equal rates.

22.  Substances must pass through transported proteins to
get through the cell membrane.
 The cell membrane is selectively permeable.
 Carrier proteins bind to the molecule that they
transport across the membrane.
 Selective permeability : integral membrane proteins
allow the cell to be selective about what passes through
membrane.
 Channel proteins have a polar interior allowing polar
molecules to pass through.
 Carrier proteins bind to specific molecule to facilitate
its passage.

24.  Carrier proteins bind to specific molecule to facilitate
its passage

25.  Osmotic concentration is determined by the
concentration of all solutes in solution.

26.  Active transport
 Requires energy – ATP used directly or
indirectly to fuel active transport.
 Able to moves substances against the
concentration gradient-from low to high
concentration.
-allows cells to store concentrated substances.
 Requires the use of carrier proteins.

28.  Bulk transport of substances is accomplished by
1.Endocytosis –movement of the substances into the cell.
2.Exocytosis –movement of the substances out of the
cell.
Endocytosis: occurs when the plasma membrane
envelops food particles liquids.
1.phagocytosis: the cell takes in particulate matter.
2.pinocytosis:the cell takes in only fluid.
3.receptor-mediated endocytosis-specific molecules are
taken in after they bind to a receptor.

29.  Interacellular space in closely packaged tissue is
about 20 nm .the cells are bound together by the
specific adhesive glycoprotein.
 Epithelial cells are adhere to each other through
glycoproteins called cadherins.
 Modified cell membrane contributing in cohesion and
communication are called cell junctions.

30.  There are three types of cell junctions
1.Tight junctions or occluding junctions
2. Adhering junctions
3.Communicating junctions

31.  Found in epithelial tissues.
 Also known as “tight junctions”
 Do not allow passage of small molecules form
impermiable membrane
 Types :
1.Zonula Occludens
2.Fascia Occludens

32.  Encircles the entire cell perimeter.
 Occludes the interacellular space
 Series of local fusions
 The adjacent cell membranes approach each other,
outer leaflets fuse ,diverge again and then fuse again.
 At fusions sites specific trans membranous proteins
named (occludins and claudins) perform the binding
function
 Less in PCT and more in the intestinal mucosa.

33.  A strip like tight junction of limited extent .
 Found between the endothelial cells of the blood
vessels.

34.  Anchoring junctions
 Provide cell-cell or cell to basal lamina adherence
 Types
1.Zonula adherens
2.Fascia adherens
3.Macula adherence (Desmosomes)
4.Hemidesmosomes

35.  A belt like junction .
 No fusion of cell membrane.
 Trans membraneous glycoprotein “ E-cadherin”
occupies intracellular gap.
 E-cadherin links to adherent proteins in cytoplasm
which are :
1.Cadherin
2.Vinculin

36.  Structurally it is similar to zonula adherence.
 But its cell junction is strip–like (not ring-like or belt –
like).
 i.e cardiac muscle cells.

37.  Macula adherins are commonly known as desmosomes.
 “spot-weld” like junctions.
 Randomly distributed along lateral plasma membranes
of the cell in simple epithelium
 In stratified epithelium it is distributed throughout the
plasma membrane
 It is also found in cardiac muscle cells
 Cell membrane in the region of junctions are seen
further apart (30mm) than the usual gap .

38.  Electron dense attachment plaques are loacated opposite
to each other on the cytoplasmic aspects.
 Intermediate filaments of the cytoskeleton are anchored
to the attachment plaques
 Two types of transmembranes glycoproteins named
desmogleins provide adherence

39.  These junction serve to anchor the epithelial cells to the
basal lamina.
 A hemidesmosomes is a spot like adhering
junctionjwhich gives appearance of half desmosome.
 In hemidesmosome transmembrrane linker proteins are
integrins
 The cytoplasmic intermediate filaments of keratin are
inserted in to the attachment plaque.

40.  Characterized by presence of minute tubular
passageways.
 Provide direct cell to cell communication.
 Tubular passages allow movement of ions and other
small molecules between adjacent cells.

41.  Gap junction are also called “nexus” which are
communicating junctions,occur frequently between the
epithelial cells.
 Also found in cardiac muscle cells,smooth
muscles,nurons ,astrocytes and osteocytes
 Plasma membrane of the adjoining cells are closely
opposed with a gap of only 2 nm.
 The gap junction contains closely packed numerous
tubular intercommunicating channels.

42.  The lumens of the channels of gap junction have an
average diameter of 1.5 nm.
 These channels permit free passage of ions, sugar and
amino acids.
 In cardiac and smooth muscles the gap junction
provides electrical coupling of the adjacent cells.
 Gap junction are frequently found in embryonic cells.

44.  Mitosis
 The process of cell division which results in the
production of two daughter cells from a single parent
cell.
 The doughter cells are identical to one another and to
the original parent cell.

45. 1. Interphase
2. Prophase
3. Metaphase
4. Anaphase
5. Telophase

46.  DNA replicated
 Organelles replicated
 Cell increases in size

47.  The cell prepare for nuclear division.
 Chromosomes become visible under light microscope.
 Threads become shorter and thicker consist of two chromatids
joined by centromere.
 Nucleoli disappears.
 Centrioles seprates and migrate to each pole and starts giving
out mitotic spindle.

48.  The cell prepares chromosomes for division
 Chromosomes line up at the center of the cell.
 Spindle fibers attached from doughter cells to chromosomes at
the centromere.
 Equatorial plate is formed.
 Microtubules of mitotic spindle are attached at centromere.
 Microtubules exert pull on the chromosomes.

50.  The chromosomes divide
 Spindle fibres pull chromosomes apart.
 Half of each chromosome (called chromatid ) moves to each
doughter cell.
 Chromatids seprate and move to respective poles as an
independent chromosomes .
 In human cell two identical sets of 46 chromosomes move to
the opposite poles.

52.  The cytoplasm divides
 A constriction called clevages forrow appears in the
middle of elongated cell.
 Nuclear envelop is formed enclosing chromosomes
 2 nuclei form.
 Cell wall pinches in to form the 2 new doughter cells.

54.  Meiosis is the type of cell division by which germ cells
(eggs and sperm) are produced.
 One parent cell produces four doughter cells.
 Doughter cells have half the number of chromosomes
found in original parent cell.
 During meiosis , DNA replicates once but the nucleus
divides twice.
 Four stages can be described for each division of the
nucleus.

55.  Prophase is much longer consisting of five stages.
1. Leptotene : chromosomes becomes visible in the
nucleus.
2. Zygotene:homologus chromosomes come together
along their entire length and synapses are formed.
3. Pachytene: chromosomes become thicker and
shorter. Each chromosome pair is bivalent.

56. 4.Diplotene :chromosomes began to nseprate along their entire
length.Each bivalent consists of four chromatids.
5.Diakinesis:sepration of chromosomes continue.Nucleolus and
the nuclear envelop disappeares.

57.  A spindle of microtubules is produced by centrioles.
 Equatorial plate is formed.
 The bivalent chromosome pairs align in the centre of
spindle.

58.  Chromosomes of homologus pairs completely seprates
and move to opposite poles.
 No division of centromere occurs and the whole
chromosomes move to opposite poles.

59.  Nuclei are reconstructed
 The parent cell is divided into two daughter cells.
 Each daughter cell contains haploid (23) chromosomes.
 Each chromosome is double structured consisting of
two sister chromatids.

60. Mitosis Meiosis
Cell divides once Cell divides twice
Two daughter cells Four haploid daughter cells
Genetic information is
identical
Genetic information is
different

61.  Cell signaling is part of complex system of communication
that governs basic activities and coordinates cell actions.
 The ability of cells to perceive and correctly resspond to their
microenvironment is the basis of development, tissue
repair,and immunity as well as normal tissue homeostasis.
 Classification:
The signals can be categorized based on the distance between
signaling and responder cells,signaling within , between and
among the cells subdivided into the

63. 1. Intracrine signals are produced by the target cell that stays
within target cell.
2. Autoacrine signals are produced by target cell, are secreated
and affect the target cell itself via receptors,sometimes
autocrine cells can target cells close by if they are tha same
type of cell as the emitting cell. An example of this is
immune cells.
3. Juxtacrine signals target adjacent (touching) cells.these
signals are transmitted along the cell membranes via protein
or lipid components integral to the membrane and capable of
affecting either the emitting cell or cells immediately
adjacent.
4. Paracrine signals target cells in the vicinity of the emitting
cell. Eg. Nutotanmitters.

64. 5. Endocrine signals distant cells.Endocrine cells
produce hormones that travel through the blood to
reach all parts of the body.
6. Some cell-cell communication requires direct cell-
cell contact. Some cells can form gap junctions that
connect their cytoplasm to the cytoplasm of adjacent
cells.

65.  In which two adjacent cells must make physical contact in
order to communicate.This requirement for direct contact
allows for very precise control of cell differentiation during
embryonic development.In the worm caenorhabditis
eleagans,Two cells of the developing gonad each have an
equal chance of terminally differentiating or becoming a
uterine precursor cell that continues to divide.The choice of
which cell continues to provide is controlled by competition
of cell surface signals.One cell will happen to produce more
of cell surface protein that activates the notch receptor on
the adjacent cell.

66.  Paracrine signals such as retinoic acid target only cells
in the vicinity of the emitting cell.Nurotransmitters
represent another example of a paracrinr ignal.Some
signaling molecules can function as both a hormone
and a nurotransmitter.For example,epinephrine and
norepiephrine can funtion as hormones when released
from the adrenal gland and are transported to the heart
by way of the blood stream.

67.  Synaptic signaling is the special case of paracrine
signaling (for chemical synapses) or juxtacrine
signaling (for electrical synapses) between the nurons
and atrget cells.Signaling milcecules interact with
target cell as a ligand to cell surface receptors,and/or by
entering into the cell through its membrane or
endocytosis for intracrine signaling.
 This generally results in the activation of second
messengers,leading to various physiological effects.

68.  Many cells signals are carried by molecules that are
released by one cell and move to make contact with
another cell.
 Endocrine signals are called hormones.Hormones are
produced by endocrine cells and they travel through the
blood to reach all parts of the body. Specificity of
signaling can controlled if only some cells can respond
to a particular hormone.