PLACENTA: STRUCTURE, DEVELOPMENT AND FUNCTIONS

Abstract:

This thesis discusses the embryonic development, morphological structure, and main functional significance of the placenta. The placenta is an important temporary organ that performs metabolic exchange, hormonal regulation, and protective functions between the mother and the fetus.

Keywords: placenta, fetus, trophoblast, chorion, hormones, blood circulation

Introduction

The placenta is a temporary organ formed during pregnancy that ensures the physiological connection between the mother and the fetus. Its proper development plays a crucial role in the normal growth and development of the fetus.

Main part

Development of the placenta

The placenta is formed as a result of implantation of the blastocyst into the uterine mucosa after fertilization. Trophoblast cells differentiate into cytotrophoblast and syncytiotrophoblast layers. Through these layers, metabolic exchange between the mother and the fetus is established.

Morphological structure

The placenta has a disc-like shape and consists of two main parts:

Maternal part — decidua basalis

Fetal part — chorion frondosum

The placenta contains numerous villi (chorionic villi), which are richly supplied with blood vessels. Through these structures, exchange occurs without direct mixing of maternal and fetal blood.

Functions

The placenta performs the following main functions:

Transport function – delivers oxygen, glucose, amino acids, and other nutrients to the fetus

Excretory function – removes carbon dioxide and metabolic waste

Endocrine function – produces hormones such as progesterone, estrogen, and human chorionic gonadotropin (hCG)

Protective function – acts as an immunological barrier against certain harmful agents

Clinical significance

The location and functional state of the placenta directly affect the course of pregnancy. Conditions such as placenta previa and placental insufficiency can lead to serious complications in fetal development.

Conclusion

The placenta is an essential temporary organ that ensures fetal viability. Any disturbances in its structure or function can negatively affect pregnancy. Therefore, studying the development and function of the placenta is of great importance in medicine.

Mamadiyorova Durdona

Uzbekistan

ASCARIS (ASCARIS LUMBRICOIDES) AND ITS EFFECT ON THE HUMAN BODY

Abstract:

This thesis discusses the parasite Ascaris, its biological characteristics, life cycle, and its effects on the human body. It also provides information about the prevention of ascariasis.

Keywords: Ascaris, parasite, ascariasis, helminth, intestine, larva, infection.

Introduction:

Ascaris is one of the large helminths that live in the human intestine and causes the disease ascariasis. This parasite mainly enters the human body when hygiene rules are not followed.

Main part:

Ascaris lumbricoides belongs to the group of roundworms and can reach a length of 20–40 cm. It mainly lives in the small intestine and feeds on nutrients.

The life cycle of the parasite is complex: eggs are released into the external environment through feces and re-enter the human body through contaminated water or food. The larvae migrate from the intestine through the bloodstream to the lungs, then are swallowed again and return to the intestine where they mature.

Ascaris causes several harmful effects in the body:

digestive disorders

allergic reactions

intestinal obstruction (in severe cases)

general weakness and weight loss

Conclusion:

Ascariasis is one of the most widespread parasitic diseases. To prevent it, it is important to follow personal hygiene rules, thoroughly wash fruits and vegetables, and consume clean drinking water

Ashurova Parizoda 

Uzbekistan

HEMATOPOIESIS: DEVELOPMENT AND SIGNIFICANCE

Abstract:

This thesis discusses the process of blood formation—hematopoiesis, its stages, main organs, and biological significance. Hematopoiesis ensures the continuous renewal of blood cells in the body.

Keywords: hematopoiesis, erythrocyte, leukocyte, platelet, bone marrow, stem cells

Introduction

Hematopoiesis is the process of formation and development of blood cells in the body. This process continues throughout human life and is essential for the normal functioning of the organism.

Main part

Stages of hematopoiesis

Hematopoiesis is divided into embryonic and postnatal periods. During the embryonic period, blood formation initially occurs in the yolk sac, then in the liver and spleen. After birth, the main hematopoietic organ is the red bone marrow.

Formation of blood cells

All blood cells develop from hematopoietic stem cells. They differentiate into the following main types:

Erythrocytes – responsible for oxygen transport

Leukocytes – involved in immune defense

Platelets – play an important role in blood clotting

Regulation of hematopoiesis

Hematopoiesis is regulated by hormones and biologically active substances. For example, erythropoietin stimulates the production of erythrocytes.

Clinical significance

Disorders of hematopoiesis can lead to various diseases, including anemia, leukemia, and other blood system disorders.

Conclusion:

Hematopoiesis is a vital biological process that ensures the continuous renewal of blood cells. Its normal functioning is essential for maintaining a healthy life.

Xamroyeva Shaxlo  Uzbekistan

The beautiful childhood!!!

Don’t block 

The road

Of the beautiful childhood. 

Oops!

How ridiculous thought!

The time

Can’t return 

Just hold the memory 

With crescent charm

The flying mind.

With golden kites 

Myriad hues of mind

Letter to all

Don’t miss the pool

Of the colourful childhood. 

Happy rhyme

The sun smiles

A Shimmering part of life

Can’t be lost forever 

Make the golden canvas, at last.

YOU ARE THE BEGINNING

Your soul is a boundless sky,

Its stars are ever watchful, never sleeping,

Like silver flowers in an indigo field.

The garden where our souls met,

Beneath a canopy of fire that doesn’t burn the skin,

But warms the depths of our being.

In the gentle sway of your spirit 

and the light of your gaze, I see the dance of shadows,

When the soft twilight of your presence 

meets the golden light of dawn,

Victorying over every night with a radiant smile.

You are the beginning and the end,

When the world remains a mountain shrouded in mist,

And the road is long and winding through the forest of time,

Your heart has become the melody of my blossoms,

The pulse of the hidden stream 

that carries my song to the sea.

You are the music the wind whispers to the leaves,

The song felt before it is heard.

In your serene stillness,

A captivating beauty is revealed, 

like a wildflower at midnight.

A beauty that glows with a faint, burning flame. 

It is a spirit that rises and stretches 

until it touches the edge of infinity.

I see you in the purity of morning dew,

Water as clear as a mountain spring,

A spirit as wild as the west wind.

Our love is an ocean without limits,

Without a bottom, sweet and eternal.

In the features of your face, 

in the light of your eyes, 

I find the beginning and end of every path.

You are the first breath in our journey,

And the radiance of all that is written for us to be.

Your spirit is the beginning and end of my path.

Good morning with good wishes

By

Manik Chakraborty. 

Good morning with good wishes

The colorful morning light,

Let the earth rise with laughter again

Let the blackness be erased.

Flowers will bloom with the song of birds

Bees will run,

Flying in confusion

They will steal the honey from the flowers

The wind will blow, the sky will be colored

With the murmur of the river,

Nature will laugh again

With the song of the fisherman

Love without tears

I have built a house on the desert sands 

My chest is filled with lamentation, 

Love without tears is a dream of broken happiness. 

The firefly bird in the darkness 

Is flying in search of light, 

The fire of treachery burns gunpowder 

My heart is burning. 

Seeing the glow in the blue sky 

A bird awake at night, 

Waiting for it to come, 

I live daily looking for the way. 

The artist is painting a picture in the folds of her red saree, 

That lost magic 

Is calling me closer