ఋతు చక్రం 1 వ భాగము:  శరీర ధర్మ శాస్త్రము

సంతానోత్పత్తి వ్యవస్థలో భాగంగా పరిగణించబడే అవయవాలలో నెలనెల జరిగే జీవ మార్పులు ఋతు చక్రం లో భాగం. ఇది అండాశయాలు (ovaries), గర్భాశయం (uterus), మరియు యోని (vagina) వంటి స్త్రీ పునరుత్పత్తి అవయవాలు కలిగి ఉన్న వ్యక్తులలో కనిపించే సహజ ప్రక్రియ. ప్రతి నెల, అండాశయాలు ఒక అండం (Ova or egg) అని పిలువబడే ప్రత్యేక బీజ కణాలు ఉత్పత్తి చేస్తాయి.  ఇలా విడుదలైన అండం లైంగిక సంపర్కం సమయంలో శుక్రంతో (sperm) ఫలదీకరణం (fertilize) చెంది గర్భకోశంలో పిండంగా తయారవుతుంది.  

ఆ పిండం గర్భాశయం (గర్భం) యొక్క గోడకు అతుక్కుపోతుంది. గర్భం దాల్చే సమయంలో క్రమంగా కొత్త శిశువుగా ఎదిగి చివరికి కాన్పు/ప్రసవంతో బయటకు వస్తుంది.  అందుకే, ప్రతి నెల, అండం విడుదల అయ్యే ముందు బిడ్డసంచిలో ఫలదీకరణం చెందిన అండం అభివృద్ధి చెందడానికి అనువైన ప్రదేశంగా తయారవుతుంది.  ఇందుకోసం గర్భాశయం యొక్క గోడ రక్తనాళాలతో నిండి మందంగా తయారవుతుంది.  పిండం గర్భాశయం గోడలకు అతుక్కుని ఉండి జీవించడానికి, పెరగడానికి అవసరమైన పోషణను అందుకుంటుంది. అండం శుక్రంతో ఫలదీకరణం చెందకపోతే అంటే గర్భధారణ జరగని పరిస్థితుల్లో అది స్రావమైపోతుంది. గర్భాశయం లోని గోడలని కప్పుతూ ఉండే మృదువైన ఎండోమెట్రియమ్ (Endometrium) అనే లోపలి పొర పీరియడ్ బ్లడ్ రూపంలో ఒక నిర్ధిష్టమైన కాల వ్యవధిలో విసర్జించబడి, తిరిగి కొత్తగా తయారు అవుతుంది. ఈ విధంగా విసర్జించబడిన స్రావాల్ని ఋతుస్రావం, బహిష్టు, నెలసరి అంటారు. 

సాధారణంగా డిశ్చార్జి లేదా బహిష్టు, రక్తం, రక్తపు గడ్డలు, గర్భాశయ గోడ నుండి స్రవించే కణజాలం, నీరు, శ్లేష్మం మరియు బ్యాక్టీరియాను కలిగి ఉంటుంది. సాధారణంగా రక్తంలో ఐరన్, కాపర్ ఉండటం, అలాగే, ఆరోగ్యకరమైన యోనిలో నివసించే బ్యాక్టీరియా ఉండటం వల్ల పీరియడ్ బ్లడ్ వాసన వస్తుంది.

মাসিক চক্র ধারাবাহিক – প্রথমভাগ- জীববিদ্যা

মাসিকচক্র চলাকালীন স্ত্রী জননতন্ত্রের প্রতিটি অঙ্গের চক্রাকার জৈবিক পরিবর্তন ঘটে। বিভিন্ন স্ত্রী জনন অঙ্গ যেমন ডিম্বাশয়(Ovary), জরায়ু(Uterus), সার্ভিক্স, যোনি(Vagina) সম্পন্ন স্ত্রী দেহে মাসিক চক্র একটি স্বাভাবিক ঘটনা। প্রতি মাসে ডিম্বাশয় একটি করে বিশেষ কোষ তৈরী করে যা জনন একক হিসেবে কাজ করে। এই একক হল ডিম্বাণু বা ওভাম যা যৌন মিলনের সময় প্রজনন নালীর মধ্যে ঢুকে পড়া শুক্রাণুর সাথে যুক্ত হয়।

গর্ভাবস্থাকালে, একটি ডিম্বাণু(Egg) ও একটি শুক্রাণু(Sperm) যুক্ত হয়ে তৈরী করে একটি কোষ, যা থেকে তৈরী হয় ভ্রূণ, ভ্রূণ আটকে থাকে জরায়ুর দেওয়ালে এবং ক্রমশ রূপান্তরিত হয় পূর্ণাঙ্গ মানবশরীরে যা শেষপর্যন্ত জন্ম নেয়। তাই প্রতিমাসে, ডিম্বাণু ও শুক্রাণু মিলিত না হলে জরায়ু তার অনুকূল পরিবেশ তৈরী করে যা পরবর্তীকালে নয় মাসের মধ্যে ভ্রূণের একটি নতুন মানবশরীর রূপায়ণের ক্ষেত্র প্রস্তুত করে। ভ্রূণের বেঁচে থাকা ও বড় হওয়ার পুষ্টির জন্য এবং ভ্রূণকে জরায়ুর দেওয়ালে আটকে রাখার জন্য জরায়ুর দেওয়াল ক্রমশ পুরু ও রক্তজালিকাপূর্ণ হয়ে ওঠে।ডিম্বাণু ও শুক্রাণু মিলিত না হলে জরায়ুর দেওয়ালের পুরুত্ব মাসিকচক্রের রক্তের আকারে শরীর নিঃসৃত করে।

মাসিকের রক্তের গঠনগত উপাদানগুলির মধ্যে পড়ে প্রচুর পরিমাণ রক্তকণিকা, কিছু সংখ্যক রক্তপিন্ড, জরায়ুর দেওয়ালে যুক্ত কলা এবং যোনিকোষ ও সার্ভিক্স নিঃসৃত তরল যা মূলত জল, আয়ন, মিউকাস(একপ্রকার পিচ্ছিল তরল) ও ব্যাকটেরিয়া নিয়ে তৈরী। রক্তের ধাতব আয়ন যেমন লোহা, তামা ও একটি স্বাস্থ্যকর যোনিতে উপস্থিত ব্যাকটেরিয়া মাসিকচক্র নিঃসৃত রক্তের বিশেষ গন্ধের কারণ।

The Menstrual Cycle Series – Biology

The menstrual cycle includes all the cyclical biological changes that happen in organs considered to be part of the female reproductive system. It is a natural phenomenon seen in people having female reproductive structures like the ovaries, the uterus, the cervix, and the vagina.  Every month, the ovaries produce special cells acting as reproductive units called eggs or ova that can fuse with sperms entering inside the female reproductive tract during sexual intercourse. 

Parts of the female reproductive system

If an egg and a sperm fuse, they will form a single cell that will become the embryo, stick to the wall of the uterus(womb) and gradually grow into a new individual over the course of the pregnancy, eventually becoming for birth. That is why, every month, in anticipation of the event of an egg-sperm fusion, the uterus prepares itself to become a suitable place where the embryo can develop into a new human being for the next nine months. The wall of the uterus becomes thick and full of blood vessels for the embryo to bind to it and receive nourishment to survive and grow. When the egg- sperm fusion does not occur, the body gets rid of the thickenings on the wall of the uterus in the form of menstrual or period blood. 

Illustration of the menstrual cycle

Thus, period blood usually contains copious amounts of blood, a few blood clots, tissues shed from the uterus wall, and secretions from the cells of the vagina and cervix that consist of water, ions, mucous, and bacteria. The smell of period blood is due to the presence of all the metal ions like iron, copper, and the bacteria that live in a healthy vagina.