Fins are the most distinctive morphological features of fish and they plays a predominant role for locomotion of fish under the water. It is important to know how many kinds of fins are present and their precise functions.
Fishes possess dermal scales on the body for protection. Each scale is made of dentine that is secreted by dermal papilla which is a group of specialized neighbouring tissues. The exposed
portion of scale is covered with a layer of hard enamel to minimise wear and tear. Ancient
fishes generally had thick bony scales while the modern fishes have evolved thin and flexible
scales for more agility.
Fins are the most distinctive morphological features of fish and they plays a predominant role for locomotion of fish under the water. It is important to know how many kinds of fins are present and their precise functions.
Fishes possess dermal scales on the body for protection. Each scale is made of dentine that is secreted by dermal papilla which is a group of specialized neighbouring tissues. The exposed
portion of scale is covered with a layer of hard enamel to minimise wear and tear. Ancient
fishes generally had thick bony scales while the modern fishes have evolved thin and flexible
scales for more agility.
are worm-like parasites. The clinically relevant groups are separated according to their general external shape and the host organ they inhabit. There are both hermaphroditic and bisexual species.
The definitive classification is based on the external and internal morphology of egg, larval, and adult stages.
Helminth is a general term meaning worm. The helminths are invertebrates characterized by elongated, flat or round bodies.
In flatworms or platyhelminths (platy from the Greek root meaning “flat”) include flukes and tapeworms.
Roundworms are nematodes (nemato from the Greek root meaning “thread”).
The main function of gills is respiration...In gills, there are many hair like projections called gill filaments..in gill filaments, there are number of lamella, from transfer of gases and water occur..
Introduction
Ostracoderms (shell-skinned) are of several groups of extinct, primitive, jawless fishes that were covered in an armour of bony plates.
They appeared in the Cambrian, about 510 million years ago, and became extinct towards the end of the Devonian, about 377 million years ago. They were quite abundant during the upper Silurian and Devonian periods. Most of fossils of Ostracodermi were preserved in the bottom sediments of freshwater streams.
However, the opinion is sharply divided as to whether their habitat was freshwater or marine.
The first fossil fishes that were discovered were ostracoderms.
The Swiss anatomist Louis Agassiz received some fossils of bony armored fish from Scotland in the 1830s.
The ostracoderms resembled the present day cyclostomes (lampreys and hagfishes) in many respects and together with them constitute a special group of jawless vertebrates, the Agnatha.
Characteristics: They use gills exclusively for respiration but not for feeding . Earlier chordates with gills used them for both respiration and feeding. Ostracoderms had separate pharyngeal gill pouches along the side of the head, which were permanently open with no protective operculum. mostly small to medium-sized fishes, protected by a heavy, bony dermal (derived from skin) armor. bottom-dwellers; filter-feeders or grazers. no paired fins, but many with stabilizing paired flaps on either side of head.
(1) Ostracoderms were the first vertebrates.
(2) They were popularly called armoured fishes.
(4) They lived in freshwater.
(5) They were bottom dwellers.
(6) Their body was fish-like and did not exceed 30 cm in size.
(7) Paired fins were absent.
(8) Median and caudal fins were present.
(9) The caudal fin was of heterocercal type.
(10) The head and thorax were covered by heavy armour of bones. It protected ostracoderms from the giant scorpion like arthropods, eurypterids.
(11) Bony skull was well developed.
(12) Mouth was mostly present on the ventral side.
(13) They were having large number of gill slits.
(14) The nervous system had 10 pairs of cranial nerves.
(15) The head had a pair of lateral eyes, and a median pineal eye.
(16) They were filter feeders, feeding like a vacuum cleaner.
(17) The endoskeleton was either bony or cartilaginous.
Fish are the gill-bearing aquatic craniate animals that lack limbs with digits. They form a sister group to the tunicates, together forming the olfactores. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups.
are worm-like parasites. The clinically relevant groups are separated according to their general external shape and the host organ they inhabit. There are both hermaphroditic and bisexual species.
The definitive classification is based on the external and internal morphology of egg, larval, and adult stages.
Helminth is a general term meaning worm. The helminths are invertebrates characterized by elongated, flat or round bodies.
In flatworms or platyhelminths (platy from the Greek root meaning “flat”) include flukes and tapeworms.
Roundworms are nematodes (nemato from the Greek root meaning “thread”).
The main function of gills is respiration...In gills, there are many hair like projections called gill filaments..in gill filaments, there are number of lamella, from transfer of gases and water occur..
Introduction
Ostracoderms (shell-skinned) are of several groups of extinct, primitive, jawless fishes that were covered in an armour of bony plates.
They appeared in the Cambrian, about 510 million years ago, and became extinct towards the end of the Devonian, about 377 million years ago. They were quite abundant during the upper Silurian and Devonian periods. Most of fossils of Ostracodermi were preserved in the bottom sediments of freshwater streams.
However, the opinion is sharply divided as to whether their habitat was freshwater or marine.
The first fossil fishes that were discovered were ostracoderms.
The Swiss anatomist Louis Agassiz received some fossils of bony armored fish from Scotland in the 1830s.
The ostracoderms resembled the present day cyclostomes (lampreys and hagfishes) in many respects and together with them constitute a special group of jawless vertebrates, the Agnatha.
Characteristics: They use gills exclusively for respiration but not for feeding . Earlier chordates with gills used them for both respiration and feeding. Ostracoderms had separate pharyngeal gill pouches along the side of the head, which were permanently open with no protective operculum. mostly small to medium-sized fishes, protected by a heavy, bony dermal (derived from skin) armor. bottom-dwellers; filter-feeders or grazers. no paired fins, but many with stabilizing paired flaps on either side of head.
(1) Ostracoderms were the first vertebrates.
(2) They were popularly called armoured fishes.
(4) They lived in freshwater.
(5) They were bottom dwellers.
(6) Their body was fish-like and did not exceed 30 cm in size.
(7) Paired fins were absent.
(8) Median and caudal fins were present.
(9) The caudal fin was of heterocercal type.
(10) The head and thorax were covered by heavy armour of bones. It protected ostracoderms from the giant scorpion like arthropods, eurypterids.
(11) Bony skull was well developed.
(12) Mouth was mostly present on the ventral side.
(13) They were having large number of gill slits.
(14) The nervous system had 10 pairs of cranial nerves.
(15) The head had a pair of lateral eyes, and a median pineal eye.
(16) They were filter feeders, feeding like a vacuum cleaner.
(17) The endoskeleton was either bony or cartilaginous.
Fish are the gill-bearing aquatic craniate animals that lack limbs with digits. They form a sister group to the tunicates, together forming the olfactores. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups.
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 :)
Skate Fish Introduction, Morphology & it's Characteristics.meemail377
Skate fish, also known simply as skates, are cartilaginous fish belonging to the family Rajidae. They are found in oceans worldwide, primarily in temperate and cold waters. Skates have a flattened body with large pectoral fins that resemble wings, allowing them to "fly" gracefully through the water. They are bottom-dwellers, often found on sandy or muddy seabeds, where they feed on small fish, crustaceans, and mollusks. Skates are known for their unique reproductive strategy, with females laying eggs in leathery egg cases known as mermaids' purses. They are commercially fished for their meat, which is firm and white, resembling that of other types of seafood like scallops or crab. However, some species of skates are vulnerable to overfishing and habitat degradation, highlighting the need for sustainable management practices.
There are main 5 classes of living echinoderms:
crinoids (sea lilies and feather stars); asteroids (STARFISH); ophiuroids (brittle stars); echinoids (SEA URCHINS, etc); and holothuroids (sea cucumbers).
Echinoderms have been well preserved as FOSSILS; all existing classes and several others now extinct were present in the Ordovician (505-438 million years ago). They may have originated in the Precambrian (over 570 million years ago).
Common name : sea lilies, Sea Stars(STARFISH), sea urchins, sea cucumbers, and brittle stars.
Habitat
Echinoderms occupy all habitats including coral reefs, mangroves, seagrass and soft-bottom areas.
Except for a few species which inhabit brackish waters, all echinoderms are benthic organisms found in marine environments. Echinoderms inhabit depths ranging from shallow waters at tide lines to the deep sea.(Barnes, 1987; Brusca and Brusca, 2003; University of Alabama Center for Communication and Educational Technology, 2000; Waggoner, 1999)
Habitat Regions
• temperate
• tropical
• polar
• saltwater or marine
Aquatic Biomes
• brackish water
Other Habitat Features
• intertidal or littoral
GeoGraphy and eco-system
Geographic Range
Mainly a marine group, echinoderms are found in all the oceans. (Brusca and Brusca, 2003)
BIOGEOGRAPHIC REGIONS
• arctic ocean
• indian ocean
• atlantic ocean
• pacific ocean
• mediterranean sea
Eco-system
Sea urchins are among the main herbivores on reefs and there is usually a fine balance between the urchins and the kelp and other algae on which they graze. A diminution of the numbers of predators (otters, lobsters and fish) can result in an increase in urchin numbers causing overgrazing of kelp forests with the result that an alga-denuded "urchin barren" forms.
Work cited:
Lawrence, J. M. (1975). "On the relationships between marine plants and sea urchins". Oceanographic Marine Biological Annual Review 13: 213–286.
Ecosystem Roles
Echinoderms are usually intricate parts of their ecosystems. Many asteroids are keystone species. Sea urchins, if not controlled by predators, may overgraze their habitat. Asteroids have several commensals, including polychaetes that feed on leftovers from the sea star's prey items. (Barnes, 1987; Brusca and Brusca, 2003)
Ecosystem Impact: keystone species
Corporate Storytelling for Leaders and Business .pptxPankaj Kukreti
Storytelling is the process of using fact and narrative to communicate something to your audience.
in these Slides,
Corporate storytelling is not always believable (greenwashing) If we fill our sites with improbable stories of corporate benevolence and racially-diverse stock photos of people leaping in fields, maybe we can distract people from the reality.
There is not much difference in kids and advertising ideas. if they are yours, you will feel they are the best
here we will learn how to create and make impact stories to tell.
You're only limited by your imagination.
So For what you are waiting for
Unleash your inner storyteller.
These powerpoint contain 3 ads campaign, How the Adobe (product based), cello (kitchenware based), and dps school do their advertisement in an unique way they want to show & present themselves in market
These .PPT is just right idea about me. Actually I believe in collaboration so I invite other to help me because I know when we work in collaboration we make 2+2= 5
As My Institution Ad Campaign assignment. i have to make a campaign ads . rather than thinking of other kind of stuff i like to go for wildlife conservationidea .. so that i make it ...
These slide include some bryophytes , with their description
& some characteristics feature
These include Hydrilla Verticillata, Vellisneria spiralis,pistia,
Eichhornia,Salvania etc.
these slide include type of animal interaction , wheather they are intraspecific & interspecific . which include intraction like mating, family formation,care of youngone, care of child etc intrasopecific & in interspecific it include parasitism, scavenging, predation,mutualism etc
These slide include gene therapy defines with their types like Germ line gene therapy,Somatic gene therapy.
with Need of Gene therapy
strategies of gene therapy
Methods of Gene transfer & with
GENE THERAPY FOR INHERITED DISORDERS
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Normal Labour/ Stages of Labour/ Mechanism of LabourWasim Ak
Normal labor is also termed spontaneous labor, defined as the natural physiological process through which the fetus, placenta, and membranes are expelled from the uterus through the birth canal at term (37 to 42 weeks
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
2. What are Scales ?
Scales are generally hard protective
outermost layer of many vertebrates
They also act as exoskeleton in many
organism
Scales
3. ORIGIN & TYPES..
They may be derived from dermal or
epidermal layer of skin
In Fish dermal scale are present, & are of
several types
Note :-
Fishes like cat fish , electric ray there is
no scale present & in chimaeras scales
located few region only
5. CTENOID SCALE:-
These Scale having
comb like projection
These scales are thin &
translucent.
There arrangement in
such a way one overlap
other
6. GANOID SCALE
Rhomboid in shape
These Composed of bone
with lacunae & canaliculi
Have shiny substance
ganoin
7. PLACOID SCALE
These scale consist
diamond shape bony
basal plate
Having trident spine
which projects out
In saw fish they
modified into large
spine
8. CYCLOID SCALE:-
Roughly Circular in
Outline
Commonly Found In
carps