Also known as “Recapitulation theory”

1.

2.

Also known as “Recapitulation theory”.
Also called the biogenetic law or embryological parallelism—often expressed using Ernst
Haeckel's phrase :
“Ontogeny recapitulates phylogeny”
BIOGENETIC LAW (grech, bios life of genetikos belonging to the birth, an origin) — a complex of the
theoretical generalizations describing communication between individual and historical development of
live organisms.
It was formulated in 1866 it. zoologist E. Gekkel (E.N. Haeckel):
«A number of forms through which there passes the individual organism at the development,
beginning from an ovum and finishing quite developed state, is the short, compressed repetition of
the long line of forms passed by animal ancestors of the same organism or patrimonial forms of its
look since the most ancient times of so-called organic creation, up to the present», i.e.
«ontogenesis is bystry and short repetition of phylogenesis»

3.

Arkhallaksis (Greek arche – the first, the prime cause, the beginning
+ Greek allaxis, from allasso – to change, change) – phylogenesis
type, is characterized by the fact that change of an initial laying of
body is observed at early stages of an embryogenesis and changes
the further course of ontogenesis.
a mode of progressive evolution — arkhallaksis, or change of
primary rudiments of bodies:
Arkhallaksis is characterized by transformation of the earliest stages
of ontogenesis, since its bookmark (a1, a2, a3) that can lead to
emergence of the new, being absent at ancestors bodies (E1, E2, E3)
— primary arkhallaksis, or to radical reorganization of ontogenesis of
body without essential changes of its definitivny structure —
secondary arkhallaksis. At this way of evolution reconciliation is
absent.

4.

By means of filembriogenez there is also evolutionary reduction
of bodies. Distinguish two types of a reduction: rudimentation
(underdevelopment) and afaniziya (complete disappearance). At
a rudimentation the body which is normally developed and
functioning at ancestors loses the functional value at
descendants. In this case, according to A. N. Severtsov, the
reduction is carried out by a negative arkhallaksis: a bookmark at
descendants is less and more weakly, than at ancestors,
develops more slowly and does not reach an ancestral definitivny
stage. As a result the body of descendants is underdeveloped. At
an afaniziya the reduced body not only loses the functional
value, but also becomes harmful to an organism. Ontogenesis of
such body, as a rule, begins and a nek-swarm time proceeds the
same as at ancestors, but then there is a negative anaboly — the
body resolves, and process goes as it should be, the return to
development, up to disappearance of the bookmark.

5.

Multicellular animals are often divided into vertebrates and invertebrates. Historically, this classification
dates back to ca 500 BC. During the ancient Hindi era, Charaka distinguished between the Jarayuja
(invertebrates) and Anadaja (vertebrates). In the ancient Greek era, Aristotle (ca 300 BC) recognized
animals with blood (Enaima, or vertebrates) and those without (Anaima, or invertebrates). This recognition
persisted even until Linnaeus . It was Lamarck who first explicitly proposed the vertebra-based division of
animals, ‘Animaux vertèbrès’ and ‘Animaux invertèbrès’, in place of Enaima and Anaima, respectively.
Aristotle had already recognized solitary ascidians as Tethyon around 330 BC. Carolus Linnaeus was a
botanist who devised a system for naming plants and animals. In his book Systema naturae (12th edn, vol.
1) , ascidians were included among the molluscs. Following anatomical investigations of ascidians by Cuvier
and others, Lamarck recognized these as Tunicata, namely animals enclosed with a tunic (tunica, in Latin,
meaning garment). On the other hand, cephalochordates (lancelets) were first described in mid-to-late
eighteenth century as molluscs. Although Yarrell had already noticed that lancelets have an axial rod,
calling it ‘a lengthened internal vertebral column, although in a soft cartilaginous state’, it was Alexander
Kowlevsky's discovery that both tunicates and lancelets possess notochords and dorsal neural tubes during
embryogenesis, indicating that they are close relatives of vertebrates.
The term ‘Vertebrata’ was first coined by Ernst Haeckel in 1866 , in which lancelets were of the class Acrania
of subphylum Leptocardia and all remaining vertebrates were classified into the subphylum Pachycardia
(i.e. Craniota). At that time, the Tunicata was still included, together with bryozoans, in the subphylum
Himatega of the phylum Mollusca. Following Kowalevsky's discovery of the notochord in ascidian larvae ,
Haeckel moved the Tunicata from the phylum Mollusca to the phylum Vermes, which also contained
enteropneusts (acorn worms), because he thought that tunicates were close relatives to vertebrates. He
coined the name Chordonia for a hypothetical common ancestor of the Tunicata and the Vertebrata
(including lancelets) by emphasizing the notochord as a significant diagnostic character shared by them.
Later, Haeckel redefined Chordonia (i.e. Chordata) to include the Tunicata and the Vertebrata
themselves.

6.

7.

8.

Tunicates have an open circulatory system. Blood flows through large tissue
spaces or blood channels in the tissues. They have a heart but it is a simple
tube with walls that contract to force the blood through it. Most tunicates
have channels for blood flow through the gills that have a very simple
structure. Lancelets have a closed circulatory system that resembles one of a
primitive fish. There is no heart, blood cells, or hemoglobin.

9.

Cephalochordates have a
closed circulatory
system (the blood is
enclosed in blood vessels)
but lack a central pump
(heart). Instead, the blood
is propelled by pulsation
(rhythmic contraction and
relaxation) of several blood
vessels. The blood
contains no pigments or
cells and is thought to
function largely in nutrient
distribution rather than in
gas exchange and
transport.

10.

The heart, which consists of the sinus,
one atrium, and one ventricle,
appeared in the circulation system of
lampreys The circulation system is a
closed tube type like that of higher
vertebrates, whereby blood flows in
closed vessels.
CYCLOSTOMATA
They have a closed circulatory
system with a two chambered heart.
Blood flows into the heart sand then
out to the gills. In the gills, blood
picks up oxygen from the water and
circulates throughout the body.
CHONDRICHTHYES

11.

In amphibians, reptiles, birds, and
mammals, blood flow is directed in two
circuits: one through the lungs and back
to the heart (pulmonary circulation) and
the other throughout the rest of the
body and its organs, including the brain
(systemic circulation).
Amphibians have a three-chambered
heart that has two atria and one ventricle
rather than the two-chambered heart of
fish (figure b). The two atria receive
blood from the two different circuits (the
lungs and the systems). There is some
mixing of the blood in the heart’s
ventricle, which reduces the efficiency of
oxygenation. The advantage to this
arrangement is that high pressure in the
vessels pushes blood to the lungs and
body. The mixing is mitigated by a ridge
within the ventricle that diverts oxygenrich blood through the systemic
circulatory system and deoxygenated
blood to the pulmocutaneous circuit
where gas exchange occurs in the lungs
and through the skin. For this reason,
amphibians are often described as
having double circulation.

12.

Most reptiles also have a three-chambered heart
similar to the amphibian heart that directs blood
to the pulmonary and systemic circuits (figure c).
The ventricle is divided more effectively by a
partial septum, which results in less mixing of
oxygenated and deoxygenated blood. Some
reptiles (alligators and crocodiles) are the most
primitive animals to exhibit a four-chambered
heart. Crocodilians have a unique circulatory
mechanism where the heart shunts blood from
the lungs toward the stomach and other organs
during long periods of submergence; for
instance, while the animal waits for prey or stays
underwater waiting for prey to rot. One
adaptation includes two main arteries that leave
the same part of the heart: one takes blood to
the lungs and the other provides an alternate
route to the stomach and other parts of the
body. Two other adaptations include a hole in
the heart between the two ventricles, called the
foramen of Panizza, which allows blood to move
from one side of the heart to the other, and
specialized connective tissue that slows the
blood flow to the lungs. Together, these
adaptations have made crocodiles and alligators
one of the most successfully-evolved animal
groups on earth.

13.

Birds, like mammals, have a 4-chambered
heart (2 atria & 2 ventricles), with
complete separation of oxygenated and
de-oxygenated blood.
Birds tend to have larger hearts
than mammals (relative to body size and
mass). The relatively large hearts
of birds may be necessary to meet the
high metabolic demands of flight.

14.

Aortic Valve Stenosis (AVS)
Atrial Septal Defect (ASD)
Coarctation of the Aorta (CoA)
Complete Atrioventricular Canal defect
(CAVC

15.

An atrial septal defect is a birth defect of the heart in which
there is a hole in the wall (septum) that divides the upper
chambers (atria) of the heart. A hole can vary in size and may
close on its own or may require surgery. An atrial septal
defect is one type of congenital heart defect