The document discusses pH, buffers, and their importance in maintaining blood pH homeostasis and gastric juice pH. It defines pH as a measure of hydrogen ion concentration and describes the pH scale. It explains how buffers work by achieving resistance to pH change through an equilibrium between a weak acid and its conjugate base. Important buffers mentioned are the bicarbonate buffer system, which maintains blood pH, and the acidic gastric juices, with a pH of 1-3 maintained by secreted hydrochloric acid.
Buffer is a mixture of weak acid and salt of conjugate base that resist the change in pH upon the addition of acid or base.BUFFER + H+ H+ BUFFER.
TYPES OF BIOLOGICAL BUFFER1. Bicarbonate Buffer2. Phosphate Buffer3.Protein Buffer4. Haemoglobin
Buffer is a mixture of weak acid and salt of conjugate base that resist the change in pH upon the addition of acid or base.BUFFER + H+ H+ BUFFER.
TYPES OF BIOLOGICAL BUFFER1. Bicarbonate Buffer2. Phosphate Buffer3.Protein Buffer4. Haemoglobin
Buffers are compounds or mixtures
of compounds that by their presence
in the solution resist changes in the
pH upon the addition of small
quantities of acid or alkali.
About carbohydrates, its types, physical and chemical properties, isomers and isomeric properties, important carbohydrates, medical use of some carbohydrates.
Describe in this slide the four theories of acid and base.1) Traditional theory 2) arrhenius theory 3) bronsted and lowry theory 4) lewis theory. also explained neutalisation reaction and amphoteric reactions.
Buffers are compounds or mixtures
of compounds that by their presence
in the solution resist changes in the
pH upon the addition of small
quantities of acid or alkali.
About carbohydrates, its types, physical and chemical properties, isomers and isomeric properties, important carbohydrates, medical use of some carbohydrates.
Describe in this slide the four theories of acid and base.1) Traditional theory 2) arrhenius theory 3) bronsted and lowry theory 4) lewis theory. also explained neutalisation reaction and amphoteric reactions.
Buffers biological systems acid base imbalance pH protein bicarbonate hemoglobin amino acid phosphate kidney lungs bone .............................................................................................................................................................................................................................................................................
Arrhenius concept of acids and bases, bronsted-lowry theory of acids and bases,amphoteric nature of water , characteristics of strong acids , characteristics of weak acids , characteristics of strong bases, characteristics of weak bases, conjugate acids, conjugate base,introduction on buffers , preparation of buffers, types of buffer, acidic buffer, basic buffer, how do buffers act, why doesn't the ph of buffers doesn't change , Handerson-Hasselbach equation, buffer capacity, pharmaceutical buffers, why maintainance of body ph is important, osmolarity of blood, isotonic, hypertonic and hypotonic solution, pharmaceutical buffer system,phosphate-buffered saline, methods to measure tonicity, hemolytic method, methods to adjust tonicity, cryoscopic method, NaCl equivalent method
Maintenance of pH of body fluids and its disorders for undergraduate medical students and postgraduate students in medicine, paediatrics, respiratory medicine etc
A buffer is a solution of a weak acid and its conjugate base (salt) that resists changes in pH in both directions—either up or down, when small quantities of an acid and a base(alkali) are added to it.
Lovastatin has been reported to possess anticancer properties, immunomodulatory function, and anti-inflammatory activity. In addition, it is known to play a significant role in preventing neurological disorders and bone problems.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
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2. WHAT DOES PH MEAN?
• Measure of hydrogen ion concentration.
• Measure of the acidity or alkalinity of a solution.
• pH scale ranges - 0 to 14.
• Aqueous solutions at 25°C with a pH less than 7
are acidic.
• pH greater than 7 are basic or alkaline.
• pH level of 7.0 is neutral because the concentration of
H3O+ equals the concentration of OH− in pure water.
3. PH EQUATION
• The equation for calculating pH was proposed in 1909 by Danish
biochemist Søren Peter Lauritz Sørensen:
pH = -log[H+]
• Where log is the base-10 logarithm and [H+] stands for the hydrogen
ion concentration in units of moles per liter solution. The term "pH"
comes from the German word "potenz," which means "power,"
combined with H, the element symbol for hydrogen, so pH is an
abbreviation for "power of hydrogen."
4. ACIDS AND BASES
• Bronsted-Lowry concept
• Acid- donate proton
• Base- accept proton
• When a proton donor loses a proton it becomes the corresponding proton acceptor.
• This pair makes up conjugate acid-base pair.
5. BUFFER
• A buffer solution is an aqueous solution consisting of a mixture of a weak acid and its
conjugate base, or vice versa. Its pH changes very little when a small amount of
strong acid or base is added to it.
• Buffer solutions are used as a means of keeping pH at a nearly constant value in a
wide variety of chemical applications. In nature, there are many systems that use
buffering for pH regulation like the bicarbonate buffering system is used to regulate
the pH of blood.
• Examples: Biochemical Assays- Enzyme activity depends on pH, so the pH during an
enzyme assay must stay constant.
• BUFFERING CAPACITY: The efficiency of a buffer in maintaining a constant pH on
addition of acid or base is referred to as buffering capacity.
6. PRINCIPLE
• Buffer solutions achieve their resistance to pH change because of the presence of
an equilibrium between the weak acid HA and its conjugate base A−:
HA H+ + A−
• When strong acid is added to a mixture of the weak acid and its conjugate base,
hydrogen ions (H+) are added. The A- combines with the H+ and makes HA
therefore removes H+ from the solution.
(OR)
• When strong base OH- is added to the mixture. The HA protonates the oxygen of
OH- turning that into water and also A- is formed. In this the HA removes the OH-
from the solution. Therefore pH remains constant.
OH- + HA → H2O + A−
7. TYPES OF BUFFER
• ACIDIC BUFFERS
• BASIC BUFFERS
Generally buffers are of two types
8. ACIDIC BUFFERS
• An acidic buffer is a combination of weak acid and its salt with a strong base.
I.e., weak acid and salt with strong base (conjugate base).
• Examples,
CH3COOH/CH3COONa
H2CO3/NaHCO3
H3PO4/NaH2PO4
HCOOH/HCOONa
9. MECHANISM OF ACTION OF ACIDIC
BUFFERS
• Consider a buffer system of CH3COOH (Weak electrolyte) and CH3COONa (Strong electrolyte). There will be a large
concentration of Na+ ions, CH3COO – ions, and un- dissociated CH3COOH molecules.
• When an acid is added
• If a strong acid (HCl) is added in CH3COOH / CH3COONa buffer, the changes that will occur may be represented as:
• The hydrogen ions yielded by the HCl are quickly removed as unionized acetic acid, and the hydrogen ion
concentration is therefore only slightly affected (because acetic acid is produced is very weak as compared to HCl
added).
10. • When a base is added
• If a strong base (NaOH) is added in CH3COOH / CH3COONa buffer, the changes that will occur may be represented
as:
• The hydroxyl ions yielded by the NaOH are therefore removed as water. The supply of hydrogen ions needed for this
purpose being constantly provided by the dissociation of acetic acid.
2
11. BASIC BUFFERS
• A basic buffer is a combination of weak base and its salt with a strong acid. i.e. Weak
base & salt with strong acid (conjugate acid).
• EXAMPLES:
NH4OH / NH4Cl
NH3 / NH4Cl
NH3 / (NH4)2CO3
12. MECHANISM OF ACTION OF BASIC
BUFFERS
• Consider a buffer system of NH4OH (Weak electrolyte) and NH4Cl (Strong electrolyte). There will be a large
concentration of NH4
+ ions, Cl– ions, and un- dissociated NH4OH molecules.
• When an acid is added
• If a strong acid (HCl) is added in NH4OH / NH4Cl buffer, the changes that will occur may be represented as:
• The hydrogen ions yielded by the HCl are therefore removed as water. The supply of OH- ions needed for this is
constantly provided by the ammonium hydroxide.
2
13. PREPARING BUFFER SOLUTIONS
HANDERSON HASSELBALCH EQUATION
• Determines the exact amount of acid and
conjugate base needed to make a buffer of
a certain pH, using the Henderson-Hassel
Bach equation:
pH= pKa + log (
[A−]
[HA]
)
where pH is the concentration of [H+], pKa is
the acid dissociation constant, and [ log{A-}]
and [ log{HA}] are concentrations of the
conjugate base and starting acid.
14. IMPORTANT BUFFERS IN LIVING
SYSTEMS
• Buffering is important in living systems as a means of
maintaining a fairly constant internal environment, also
known as homeostasis.
• Small molecules such as bicarbonate and phosphate
provide buffering capacity as do other substances, such
as hemoglobin and other proteins.
15. BUFFERING SYSTEM OF BLOOD
• Maintaining a constant blood pH is critical for
the proper functioning of our body.
• The buffer that maintains the pH of human
blood involves a carbonic acid (H2CO3) -
bicarbonate ion (HCO3
-) system.
• The bicarbonate buffer system is an effective
physiological buffer near pH 7.4, because the
H2CO3 of blood plasma is in equilibrium with a
large reserve capacity of CO2(g) in the air space
of the lungs.
16. • This buffer system involves three reversible equilibria between gaseous CO2 in the
lungs and bicarbonate (HCO3
- ) in the blood plasma.
• When H+ (from lactic acid produced in muscle tissue during vigorous exercise, for
example) is added to blood as it passes through the tissues, reaction 1 proceeds
toward a new equilibrium, in which the concentration of H2CO3 is increased.
17. • This increases the concentration of CO2(d) in the blood plasma (reaction 2) and thus increases the
pressure of CO2(g) in the air space of the lungs (reaction 3); the extra CO2 is exhaled.
• Conversely, when the pH of blood plasma is raised (by NH3 production during protein catabolism, for
example), the opposite events occur:
• The H+ concentration of blood plasma is lowered, causing more H2CO3 to dissociate into H+ and HCO3
-
. This in turn causes more CO2(g) from the lungs to dissolve in the blood plasma. The rate of
breathing—that is, the rate of inhaling and exhaling CO2—can quickly adjust these equilibria to keep
the blood pH nearly constant.
18. PH OF GASTRIC JUICES
• Many aspects of cell structure and function are
influenced by pH, it is the catalytic activity of enzymes
that is especially sensitive.
• Enzymes typically show maximal catalytic activity at a
characteristic pH, called the pH optimum.
• On either side of the optimum pH their catalytic activity
often declines sharply. Thus, a small change in pH can
make a large difference in the rate of some crucial
enzyme-catalyzed reactions.
19. • ▪ Gastric secretion is a colorless, watery,
acidic, digestive fluid produced in the
stomach
• Physical properties;
• Watery fluid, that has a pale yellow color
• pH is 1-3 ,
• Volume secreted per day is 2-3 L .
• The stomach secretes acid (HCl), which is
important either to the digestive process or
to control of gastric function.
• Parietal cells: Secrete HCl into the stomach
lumen where it establishes an extremely
acidic environment. This acid is important
for activation of pepsinogen and inactivation
of ingested microorganisms such as
bacteria.
• Chief cells: It secrets pepsinogen(zymogen).
Once secreted, pepsinogen is activated by
stomach acid into the active protease
pepsin.
20. REFERENCES
• Lehninger, A. L., Nelson, D. L., & Cox, M. M. (2000). Lehninger
principles of biochemistry. New York: Worth Publishers.
• Text book of medical biochemistry by MN chaterjea , Rana Shinde.
• https://courses.lumenlearning.com/introchem/chapter/ph-buffers-acids-
and-bases/
• https://bio.libretexts.org/Bookshelves/Biotechnology/Lab_Manual%3A_I
ntroduction_to_Biotechnology/01%3A_Techniques/1.07%3A_pH_and_Bu
ffers
21. MCQs
1.If a decinormal solution of NaOH is added in a mixture of weak base and its strong salt then in the following condition which option is
correct?
a) Very high change in OH– ions
b) High change in OH– ions
c) Slight change in OH– ions
d) No change in OH– ions
2. Which of the following is not a simple buffer?
a) CH3COONH4
b) NH4CN
c) H3PO4 + NaH2PO4
d) (NH4)2 CO3
3.Which of the following is not a type of Basic buffer mixture?
a) NH4OH
b) NH4Cl
c) H2CO3+Na2CO3
d) Glycine + Glycine hydrochloride
4. What is the H+ ion concentration in pure water?
a) 1×107 m
b) 1×10-7 m
c) 1×1014 m
d) 1×10-14 m
22. 5.The pH of buffer solution depends upon concentration of?
a) Strong acid
b) Strong base
c) Weak acid
d) Salt
6. . The pH can be kept constant with the help of?
a) Saturated solution
b) Unsaturated solution
c) Buffer solution
d) Non-Saturated solution
7. A solution was prepared by dissolving 0.02 moles of acetic acid (HOAc; pKa = 4.8) in water to give 1 liter of solution. What is the pH?
a) 3.00
b) 3.05
c) 3.15
d) 3.25
8. Buffers usually contain ________________ with its conjugate ____________
a) weak base, base
b) strong base, acid
c) weak acid, base
d) weak acid, acid
23. 9.Carbonic acid and bicarbonate ions buffer which of the following?
a) Cytosol
b) Cytoplasm
c) Blood
d) Lymph
10. In presence of an acid, amino group can be ____________
a) Polarized
b) Washed away
c) Protonated
d) Replaced