Cells regulate their size through diffusion and osmosis. Diffusion is the movement of substances from high to low concentration areas, while osmosis is the diffusion of water across membranes. During cell division, the cell cycle consists of interphase, where the cell grows and duplicates its DNA, and mitosis, where the cell divides into two identical daughter cells through the stages of prophase, metaphase, anaphase, and telophase. Cytokinesis then separates the cytoplasmic components of the parent cell.
Respiratory system is an important Human regulatory for breathing.
Here,I have attached the respiratory system funtions and their importance .
☆The process of respiratory system is of two types:
1.Lower respiratory system
2.Upper respiratory system
☆Rest of the respiratory system .
☆Some of the diseases associated with the both upper and lower respiratory systems.
☆Overall functions of the respiratory system.
☆Summary
☆References.
The concept is built up on basic transport mechanisms across the biological membranes including transcapillary or paracapillary transport. Attempt has been made to distinguish between the blood brain barrier and blood-CSF barrier. Cartoons were profusely used.
-Cell Division Process In Prokaryotes & Eukaryotes
-Compacting DNA into Chromosomes
-Types of Cell Reproduction
-Phases of the Cell Cycle
-Mitosis
-Meiosis
-Oogenesis & Spermatogenesis
-Comparison of Divisions
Respiratory system is an important Human regulatory for breathing.
Here,I have attached the respiratory system funtions and their importance .
☆The process of respiratory system is of two types:
1.Lower respiratory system
2.Upper respiratory system
☆Rest of the respiratory system .
☆Some of the diseases associated with the both upper and lower respiratory systems.
☆Overall functions of the respiratory system.
☆Summary
☆References.
The concept is built up on basic transport mechanisms across the biological membranes including transcapillary or paracapillary transport. Attempt has been made to distinguish between the blood brain barrier and blood-CSF barrier. Cartoons were profusely used.
-Cell Division Process In Prokaryotes & Eukaryotes
-Compacting DNA into Chromosomes
-Types of Cell Reproduction
-Phases of the Cell Cycle
-Mitosis
-Meiosis
-Oogenesis & Spermatogenesis
-Comparison of Divisions
Die Brownsche Molekularbewegung.
Die Diffusion.
Die Osmose.
Die Kapillarität.
Der Transpirationssog.
Eine Arbeitspräsentation für den Biologieunterricht in Klasse 9.
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 .
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
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.
2. A cell can’t just keep growing and growing.
- As cell gets larger, surface area to volume ratio decreases
- Less surface area for passage of nutrients and waste across the
membrane
- Substances would take too long to diffuse to where they are
needed in the cell
DIFFUSION
4. Osmosis: Diffusion of water
Water can diffuse into and out of cells based on
concentration of solute inside and outside a cell.
OSMOSIS
5. Water can move in or out of a cell, causing it to expand or shrink,
based on the type of solution it is placed in:
Hypotonic – lower solute concentration outside the cell
Isotonic – same solute concentration outside the cell
Hypertonic – higher solute concentration outside the cell
OSMOSIS
6. A hypotonic solution can swell an animal cell to the point of
lysis, but plant cells have cell walls to prevent this.
OSMOSIS
7. Passive transport: Movement of substance across a
membrane without using energy
Passive transport relies on diffusion and concentration
gradients.
PASSIVE TRANSPORT
8. Active transport: Movement of substances across a
membrane using energy against concentration gradient.
PASSIVE TRANSPORT
10. Why do cells need to divide?
-To allow an organism to
grow
-To pass on genetic material
-To assist an organism’
survival
CELL DIVISION
11. 3 stages of cell cycle:
Interphase
Mitosis (division of nuclear
material)
Cytokinesis (division of
cytoplasm)
CELL DIVISION
12. Interphase
- Cell is not dividing but
also not dormant
- Cell is active and
growing and also
preparing for division
- Sometimes called
resting phase but this
is inaccurate (real
resting phase is G0)
- DNA/chromosomes
not visible (unwound)
INTERPHASE
13. Interphase: 4 stages
Gap 0 (G0):
- Cell rest cycle
- may be temporary
or permanent (where
cells are functional
but no new cells are
produced (i.e.
neuron)
G0
INTERPHASE
14. Interphase: 4 stages
Gap 1 (G1):
- Rapid growth (4hr)
- cell takes in
nutrients for energy,
growth, repair
- Cells either go into S
or G0 after G1
G0
INTERPHASE
15. Interphase: 4 stages
S phase (S):
- 10 hrs
- DNA synthesis/
replication
- the cell duplicates
its genetic material to
make an identical
copy of its DNA
G0
INTERPHASE
16. Interphase: 4 stages
Gap 2 phase (G2):
- 3-4hr
- second period of
growth in preparation
for cell division
-cell grows larger in
size
G0
INTERPHASE
17. S phase (S): Let’s take a closer look
DNA replication
Normally
DNA
duplication
After duplication
INTERPHASE
18. Mitosis:
- A process by which somatic cells grow and divide
- Cells come from pre-existing cells
- Parent cell divides to produce two new identical daughter cells
- asexual reproduction (offspring from one parent)
- 4 phases:
MITOSIS
19. Prophase
- nuclear membrane breaks down
- chromosomes shorten and
thicken
- Other structures important for
mitosis are also forming (i.e. the
centrioles)
MITOSIS: PROPHASE
20. Prophase
- A centromere holds two copies of the same chromosome together
- Each copy of a chromosome is called a chromatid
MITOSIS: PROPHASE
21. Mother’s
side
Prophase
- A centromere holds two copies of the same chromosome
together
- Remember, every chromosome has been duplicated during the S
phase of interphase.
- Recall this:
Mitosis
Mother’s
side Mother’s
side
Colors are not accurate
MITOSIS: PROPHASE
centromere
23. Metaphase
- Microtubules (spindle fibres)
attach at the centromeres
and the chromosomes move
to the centre (the metaphase
plate)
MITOSIS: METAPHASE
metaphase plate
26. Telophase
- Chromatids arrive at opposite
poles of cell
- New membranes form around
the daughter nuclei
- Chromosomes disperse and
are no longer visible under the
light microscope
- spindle fibres disperse
MITOSIS: TELOPHASE
27. Cytokinesis
- Animal cells: the
cell membrane
pinches (forming
a cleavage furrow)
into two daughter
cells, each with
one nucleus
CYTOKINESIS: ANIMAL CELLS
28. Cytokinesis
- In plant cells, a
cell plate (made
of rigid cellulose)
is synthesized
between the two
daughter cells.
CYTOKINESIS: PLANT CELLS
