The document provides information about cell structure and organelles. It discusses:
- Cells as the basic structural and functional units of organisms.
- The cell theory proposed by Schleiden and Schwann stating that cells are the basic unit of life, all cells come from preexisting cells, and organisms are made of cells.
- Key organelles like the nucleus, endoplasmic reticulum, ribosomes, Golgi apparatus, mitochondria, and lysosomes and their functions.
The cell (from Latin cellula 'small room') is the basic structural, functional, and biological unit of all known organisms. A cell is the smallest unit of life. Therefore, cells are often described as the "building blocks of life".
For more knowledge about the science related topics please visit my website
Here is my blog web site :
https://upadhyaybiologylearner.blogspot.com
The cell (from Latin cellula 'small room') is the basic structural, functional, and biological unit of all known organisms. A cell is the smallest unit of life. Therefore, cells are often described as the "building blocks of life".
For more knowledge about the science related topics please visit my website
Here is my blog web site :
https://upadhyaybiologylearner.blogspot.com
CELL - STRUCTURE AND FUNCTIONS
discovery of cell
cell shape
cell size
cell number
parts of cells
Cells Types
Plant Cell
Animal Cell
Differences Between Plant and Animal Cells
Levels of organization of living being
Cell Division And cell Growth
All living things are made from one or more cells. A cell is the simplest unit of life and they are responsible for keeping an organism alive and functioning. This lesson to cells is the starting point for the area of biology that studies the various types of cells and how they work.
In this lesson you will learn about :
1) What is a Cell?
2) The Invention of the Microscope and the Discovery of Cell.
3) Cell Theory.
4) Cells - Number, Size, Shape and Function.
5) Structure of a Cell
6) Prokaryotic and Eukaryotic Cells.
7) The Plant and Animal cells.
8) Stem Cells.
I hope this document is helpful to you. Please share the document with your friends if you think this will benefit them. Get ready for the next lesson. Thanks.
Eukaryotic cells contain membrane-bound organelles, including a nucleus. Eukaryotes can be single-celled or multi-celled, such as you, me, plants, fungi, and insects. Bacteria are an example of prokaryotes. Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle.
This doc is created by Rehet Kaur Bhatia 8D and It is not for coping.It's made with a lot of patience and hardwork . and In this chapter we will learn about cell
La celula: la teoría celular, estructura y función. La división celularJosué Moreno Marquina
Teoría celular, cell theory
Estructura celular: membrana, citoplasma y núcleo. Membrane, cytoplasm and nucleus
Orgánulos celulares, organelles.
Mitosis y meiosis
All living organism can be categorized as prokaryotes or eukaryotes according to their cell type. This article deals with detailed about prokaryotes and eukaryotes with examples and figures and their similarities and dissimilarities.
CELL - STRUCTURE AND FUNCTIONS
discovery of cell
cell shape
cell size
cell number
parts of cells
Cells Types
Plant Cell
Animal Cell
Differences Between Plant and Animal Cells
Levels of organization of living being
Cell Division And cell Growth
All living things are made from one or more cells. A cell is the simplest unit of life and they are responsible for keeping an organism alive and functioning. This lesson to cells is the starting point for the area of biology that studies the various types of cells and how they work.
In this lesson you will learn about :
1) What is a Cell?
2) The Invention of the Microscope and the Discovery of Cell.
3) Cell Theory.
4) Cells - Number, Size, Shape and Function.
5) Structure of a Cell
6) Prokaryotic and Eukaryotic Cells.
7) The Plant and Animal cells.
8) Stem Cells.
I hope this document is helpful to you. Please share the document with your friends if you think this will benefit them. Get ready for the next lesson. Thanks.
Eukaryotic cells contain membrane-bound organelles, including a nucleus. Eukaryotes can be single-celled or multi-celled, such as you, me, plants, fungi, and insects. Bacteria are an example of prokaryotes. Prokaryotic cells do not contain a nucleus or any other membrane-bound organelle.
This doc is created by Rehet Kaur Bhatia 8D and It is not for coping.It's made with a lot of patience and hardwork . and In this chapter we will learn about cell
La celula: la teoría celular, estructura y función. La división celularJosué Moreno Marquina
Teoría celular, cell theory
Estructura celular: membrana, citoplasma y núcleo. Membrane, cytoplasm and nucleus
Orgánulos celulares, organelles.
Mitosis y meiosis
All living organism can be categorized as prokaryotes or eukaryotes according to their cell type. This article deals with detailed about prokaryotes and eukaryotes with examples and figures and their similarities and dissimilarities.
This presentation file contains all about cell discovery, cell theory, organelles which are present within the cell and cell comparison between prokaryotic and Eukaryotic organisms.
Cell Definition
What is a Cell?
Discovery of Cells
Who discovered cells?
Characteristics of Cells
Types of Cells
Prokaryotic Cells
Eukaryotic Cells
Cell Structure
Cell Membrane
Cell Wall
Cytoplasm
Nucleus
Cell Organelles
Functions of Cell
Cell Theory
A cell is the structural and fundamental unit of life.
The study of cells from their basic structure to the functions of every cell organelle is called Cell Biology.
Robert Hooke was the first Biologist who discovered cells.
All organisms are made up of cells. They may be made up of a single cell (unicellular), or many cells (multicellular).
Mycoplasmas are the smallest known cells.
Cells are the building blocks of all living beings. They provide structure to the body and convert the nutrients taken from the food into energy.
Cells are complex and their components perform various functions in an organism. They are of different shapes and sizes, pretty much like the bricks of the buildings. Our body is made up of cells of different shapes and sizes.
Cells are the lowest level of organisation in every life form. From organism to organism, the count of cells may vary. Humans have more cells compared to that bacteria.
Cells comprise several cell organelles that perform specialised functions to carry out life processes. Every organelle has a specific structure. The hereditary material of the organisms is also present in the cells.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
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.
(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.
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.
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 .
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
3. Cell
All living organisms are made up of cells. Cell is the basic structural and
functional unit of complex organisms. Cells perform all the metabolic
activities taking place at cellular level. The discovery of cells was possible
with the invention of microscope.
History of cell
• Marcello Malpighi, in 1661, proposed that plants are made of tiny
structural units called 'Utricles'.
• Robert Hooke, in 1665, observed many tiny, hollow, room like
structures in a thin slice of cork through a compound microscope and
called them ‘cells’.
• Leeuwenhoek, in 1674, with the improved microscope, discovered
free-living cells in pond water for the first time.
• Robert Brown in 1831 discovered the nucleus in the cell.
• Purkinje in 1839 coined the term 'protoplasm' for the fluid part of the
cell.
• Schleiden in 1838 and Schwann in 1839 proposed the cell theory
which stated that all plants and animals are composed of cells.
• Rudolf Virchow in 1855 further expanded the cell theory by saying
‘omniscellula-e-cellula’, which means all cells arise from pre-existing
cells.
• Cell is derived from the Latin word "Cellula" which means "a little
room".
4. Cell theory
M.J.Scleiden and TheodreSchwann proposed cell theory for the first time.
• Cell is the basic structural unit of all the organisms.
• Preexisting cells only gave rise to new cells.
• An organism has its body composed of cells.
• A single cell transfers life from one generation to another generation.
Microscopic examination of cells
Plant and animal cells are only visible only under a microscope.
• The microscopic examination of a plant cell enables us view a prominent
vacuole, nucleus, and cytoplasm.
• For the microscopic examination of an animal cell, spread the specimen on a
glass slide, and add a drop of water and methylene blue. Cells with darkly stained
spherical nuclei at their centre can be observed.
5. Nucleus: A true nucleus acts as the control centre of the cell. It is covered by a
two layered, perforated nuclear membrane allowing substances to enter and leave
the nucleus.
Nucleus is filled with semifluid colloidal substance called as nucleoplasm in which
float the nucleolus and the chromatin fibres. The nucleus contains chromosomes, which
are composed of Deoxyribonucleic acid (DNA) and proteins.
Functions of nucleus
Nucleus controls all the activities of cell
• As the nucleus carries genetic information in the form of DNA, it plays a major
role in cell division and cell development. The functional segments of DNA are
called genes.
• Nucleus plays an important role in protein synthesis and transmission of
characters from one generation to another generation.
6. Endoplasmic reticulum:
It is a network of tubules and flattened sacs perform various activities in the
cell. The space inside the endoplasmic reticulum is called as lumen.
Endoplasmic reticulum serves as a channel for the transport of proteins
between various regions of the cytoplasm.
Two types of endoplasmic reticulum are
Rough Endoplasmic Reticulum (RER) and
Smooth Endoplasmic Reticulum (SER).
7. Ribosomes: These are naked granules with no membrane. They are found
scattered in the cytoplasm or attached to the outside of the endoplasmic
reticulum.
They are the biofactories of proteins.
Ribosomes can be free ribosomes scattered in the cytoplasm or bound
ribosomes seen attached to endoplasmic reticulum.
Ribosomes are made up of two subunits, the larger subunit and the smaller
subunit. 70s ribosomes are present in prokaryotes and 80s ribosomes are
present in eukaryotes.
Functions of ribosomes
• Ribosomes are considered to be the biofactories since they are the sites of
protein synthesis.
• They are the lodging sites for many enzymes participating in the process of
protein synthesis.
8. Golgi apparatus:
These cell organelles are named after the biologist, Camillo Golgi, who first
described it. The Golgi consists of a stack of membrane-bounded cisternae located
between the endoplasmic reticulum and the cell surface.
Functions of Golgi apparatus
• It synthesises certain biopolymers.
• It also consists of some processing enzymes which alter some proteins and
phospholipids synthesised by endoplasmic reticulum.
9. Mitochondria:
These are cellular organelles termed as ‘power houses of the cells’. These are bounded
by a double membrane. The outer membrane is smooth while the inner membrane is
thrown into folds called as cristae. The cristae increase the area of cellular respiration.
Both the membranes are separated by intermembrane space. Mitochondrial matrix is
rich in respiratory enzymes
The enzymes in the mitochondria oxidise glucose molecules to produce energy in the
form of Adenosine Triphosphate or ATP.
Functions of mitochondria
• These synthesise energy rich ATP molecules.
• These help in the synthesis of fatty acid, amino acids, steroids by providing them with
biological intermediates.
10. Lysosomes:
Lysosomes are membranous sacs filled with enzymes. The enzymes are hydrolytic
enzymes which are capable of digesting cellular macromolecules. When the cell gets
damaged, the lysosome may burst and its enzymes may digest the cell itself. Hence,
lysosomes are called as ‘suicidal bags’.
Functions of lysosomes
• Help in killing foreign cells referred to as pathogens.
• Help in destroying the diseased cells.
11. INSTRUCTIONS
Read the content thoroughly.
The questions are based on the content of
slide.
There are total five multiple choice
questions.
All the questions are compulsory to answer.
12. 1. Which statement of cell is a part of cell theory
a) Cells are found in most living things
b) Cells come only from other living cells
c) All cells capture energy from sunlight
d) Cells with cell walls do not have cell membranes
13.
14.
15.
16.
17. 2. The smallest unit that perform the basic
activities of life is…….
a) a tissue
b) a cell
c) an organ
d) an organism
18.
19.
20.
21.
22. 3. One of the organelles which is considered
as bio factories synthesizing protein………
a) Ribosome
b) Endoplasmic reticulum
c) Golgi apparatus
d) Lysosome
23.
24.
25.
26.
27. 4. Which organelles known as power house of
cell……..
a) Mitochondria
b) Ribosome
c) Endoplasmic reticulum
d) Lysosome
28.
29.
30.
31.
32. 5. Which organelles helps in destroying the
diseased cells…….
a) Nucleus
b) Chloroplast
c) Lysosome
d) Ribosome