Mollusks are a large phylum of invertebrate animals that first appeared during the Cambrian period. They have soft bodies that are usually protected by an external calcium carbonate shell. Their bodies have three main zones - a head-foot, visceral mass, and mantle. There are several major classes of mollusks including bivalves like clams and mussels, cephalopods like squid and octopuses, gastropods like snails, and others. Mollusks play important roles in ecosystems as prey for other animals or by filtering water. They also have commercial and medical significance for humans.
This is PowerPoint Presentation published in Elsevier Journal.
Link here: https://www.elsevier.com/books-and-journals/book-companion/9780128498859/presentation
Insects, spiders, crabs, shrimp, millipedes, and centipedes are all arthropods. Arthropods have jointed feet, a segmented body, and an exoskeleton, a cuticle on the outside of their body. Arthropods have by far the greatest number of species of any animal group, at around 900,000 species
This is PowerPoint Presentation published in Elsevier Journal.
Link here: https://www.elsevier.com/books-and-journals/book-companion/9780128498859/presentation
Insects, spiders, crabs, shrimp, millipedes, and centipedes are all arthropods. Arthropods have jointed feet, a segmented body, and an exoskeleton, a cuticle on the outside of their body. Arthropods have by far the greatest number of species of any animal group, at around 900,000 species
Phylum Mollusca, Class Gastropoda, Torsion, Locomotion, Digestion,Reproductio...Dr. Muhammad Moosa
In this presentation, Phylum Mollusca Is described. After watching this you will learn Evolutionary Perspective of Mollusca and Relationships to Other Animals, Molluscan Characteristics, Class Gastropoda, Torsion, Shell Coiling, Locomotion, Feeding and Digestion, Other Maintenance Functions, Reproduction and Development, Gastropod Diversity, Class Bivalvia, Shell and Associated Structures Gas Exchange, Filter Feeding, and Digestion, Other Maintenance Functions Reproduction and Development, Bivalve Diversity, Class Cephalopoda, Shell, Locomotion, Feeding and Digestion, Other Maintenance Functions, Learning, Reproduction and Development, Class Polyplacophora, Class Scaphopoda, Class Monoplacophora, Class Solenogastres, Class Caudofoveata, Further Phylogenetic Considerations. It is part of BS Zoology Course, Animal diversity.
Arthropoda is coming under the Kingdom of animals,
Arthropoda is the largest group of animals. These found everywhere on the Earth.
GK. artho = jointed ; podos = foot
Mollusca of India and need for conservationAshish sahu
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda. The members are known as molluscs or mollusks. Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species
Phylum Mollusca, Class Gastropoda, Torsion, Locomotion, Digestion,Reproductio...Dr. Muhammad Moosa
In this presentation, Phylum Mollusca Is described. After watching this you will learn Evolutionary Perspective of Mollusca and Relationships to Other Animals, Molluscan Characteristics, Class Gastropoda, Torsion, Shell Coiling, Locomotion, Feeding and Digestion, Other Maintenance Functions, Reproduction and Development, Gastropod Diversity, Class Bivalvia, Shell and Associated Structures Gas Exchange, Filter Feeding, and Digestion, Other Maintenance Functions Reproduction and Development, Bivalve Diversity, Class Cephalopoda, Shell, Locomotion, Feeding and Digestion, Other Maintenance Functions, Learning, Reproduction and Development, Class Polyplacophora, Class Scaphopoda, Class Monoplacophora, Class Solenogastres, Class Caudofoveata, Further Phylogenetic Considerations. It is part of BS Zoology Course, Animal diversity.
Arthropoda is coming under the Kingdom of animals,
Arthropoda is the largest group of animals. These found everywhere on the Earth.
GK. artho = jointed ; podos = foot
Mollusca of India and need for conservationAshish sahu
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda. The members are known as molluscs or mollusks. Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species
Phylum Mollusca-my report..
sorry for some overlapping of texts... i was not able to edit it..it is actually because of the animations that i put it..... i just uploaded it directly :)
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
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.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
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.
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.
2. Description
▪ The molluscs (Americans spell it as
‘mollusks’) constitute one of the largest phyla
of animals, with close to 112,000 species to
be found worldwide. The scientific study of
mollusks is known as malacology . The
mollusks first appeared during the Cambrian
period of the evolutionary calendar. The
world mollusca has its root in the Latin
word molluscus meaning ‘thin shelled’ which
in turn is derived from the root Latin
3. ▪ This is a description of their main
characteristic -all mollusks have a soft
body, which ( with the exceptions of
from certain families) is generally
protected by an external, calcium-
shell. In the octopuses and sea-slugs
completely absent where as in squids
it is located internally.
4. Main characteristics of
Mollusca
▪ All modern mollusks have the same
fundamental body plan. There are
three distinct body zones: a head-
foot, a visceral mass and a mantle.
Some common features are :
5. 1)Bilaterally symmetrical.
2)Body has more than two cell layers, tissues
and organs.
3)Body without cavity.
4)Body possesses a through gut with mouth
and anus.
5)Body monomeric and highly variable in form,
may possess a dorsal or lateral shells of
protein and calcareous spicules.
6)Has a nervous system with a circum-
oesophagal ring, ganglia and paired nerve
chords.
7)Has an open circulatory system with a heart
and an aorta.
8)Has gaseous exchange organs called ctenidial
6.
7. The Class Bivalvia
• The bivalves (meaning "two-
shells") are perhaps the
most well known mollusks
simply because of their
history as a source of food.
Clams, mussels, oysters and
scallops are all bivalves.
• The bivalve may either
burrow through the bottom,
or attach itself to the
substrate with glue-like
strings called "byssal
threads.“
• Most bivalves feed by
filtering organic particles from
water, and therefore do not
have a radula.
• The shell is generated by
the mantle from the inside.
Pearls are made by clams,
oysters and mussels
8.
9. The Class Cephalopoda
• Although we usually think of Mollusks as
benthic (bottom dwelling), the
cephalopods have taken to a nektonic
(swimming), rather than benthic,
existence in the ocean.
• The cephalopods may not seem very
closely related to the other mollusks, but
physiologically, they are similar in internal
construction.
• Perhaps the most obvious difference
between most cephalopods and other
mollusks is the apparent lack of a shell.
• Cephalopods have the most well
developed nervous systems of all
mollusks, as well as the most well
developed eye.
• The cephalopod eye is one of the most
notable examples of convergent
evolution in all of the animal world
10. The class of Gastropoda
million years ago. No
other class has as many
species (more than 50,000)
or are as widely collected.
• The Class Gastropoda
includes the snails and
slugs. Most gastropods
have a single, usually
spirally coiled shell into
which the body can be
withdrawn, but the shell is
lost or reduced some
important groups.
• Gastropods are
characterized by "torsion,"
a process that results in
the rotation of the visceral
mass and mantle on the
foot.
• Gastropods are dioecious,
and some forms are
hermaphroditic.
Hermaphroditic forms
exchange bundles of sperm
to avoid self-fertilization
11. The class of
Monoplacophora
• Monoplacophorans are small
and limpet-like, having a single,
cap-like shell. Some organs
(kidneys, heart, gills) are
repeated serially,.
• The word Monoplacophora is
derived from three Greek
words monos=one, plax=plate
and pherein=bearing. So
it includes animals having only
one plate. It does not have any
order.The characteristics of it
are listed as below.
Examples :- Neopilina galatheae
12. ▪ They have bilaterally symmetrical and segmented body.
They have shell made up of single piece or valve.They have
head without eyes and tentacles.They have ventral and flat
foot.They have mantle which encircle the body as
a circular fold of the body wall.They have external and
serially arranged gills.They have five pairs of serially
arranged nephridia.They have sex organs in two separate
bodies.
13. The Scaphopoda
distinctive group
of mollusks commonly
known as the "tusk
shells" because their
shells are conical and
slightly curved to the
dorsal side, making
the shells look like
tiny tusks
• Scaphopods live their
adult lives buried in
sand or mud, with
their head end pointed
downwards. Only the
narrow posterior end
of the shell sticks up
into the seawater for
water exchange and
waste expulsion.
14. ▪ The scientific name Scaphopoda means "shovel
foot," a term that refers to the "head" of the animal,
which lacks eyes and is used for burrowing in
marine mud and sediments.The most distinctive
feature of scaphopods is that the tubular shell is
open at both ends, not just one end as in most
mollusks.
15. Significance
▪ Mollusks, which include land snails, freshwater
snails, mussels, clams, and slugs, are vital to
healthy ecosystems. Land snails, for example,
not only provide food for a host of small
mammals and birds, but they play vital roles
in recycling forest nutrients. Freshwater snails
also provide food for fish, including native
trout and salmon, and are also important
recyclers of plant and animal waste,
essentially keeping water clean and healthy.
16. ▪ Mollusks are of general importance within food chains and as
members of ecosystems. Certain species are of direct or indirect
commercial and even medical importance to humans. Many
gastropod species, for example, are necessary intermediate
hosts for parasitic flatworms (classTrematoda, phylum
Platyhelminthes), such as the species that cause
schistosomiasis in humans. Most bivalves contribute to the
organic turnover in the intertidal (littoral) zones of marine and
fresh water because, as filter feeders, they filter up to 40 liters
(10 gallons) of water per hour.