जीवित प्राणियों की विशेषताएं

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जीवित प्राणियों या जीव-जंतुओं में कुछ ऐसी विशेषताएं होती हैं जो उन्हें निर्जीव संस्थाओं से अलग करती हैं। इन विशेषताओं का उपयोग अक्सर जीवन को परिभाषित करने के लिए किया जाता है और इसमें शामिल हैं:
 01. कोशिकीय संगठन
 02. प्रजनन
 03. उपापचय/चयापचय (Metabolism)
 04. समस्थैतिकता (Homeostasis)
 05. आनुवंशिकता
 06. उत्तेजनाओं के प्रति प्रतिक्रिया
 07. वृद्धि और विकास
 08. विकास के माध्यम से अनुकूलन

01. कोशिकीय संगठन
  • जीवित प्राणी कोशिकाओं से बने होते हैं, जो जीवन की बुनियादी संरचनात्मक और कार्यात्मक इकाइयाँ हैं।
  •  जीव एककोशिकीय (एक कोशिका से बने) या बहुकोशिकीय (कई कोशिकाओं से बने) हो सकते हैं।
02. प्रजनन
  • जीवित प्राणी संतान पैदा करने और अपनी प्रजाति की निरंतरता सुनिश्चित करने के लिए लैंगिक या अलैंगिक तरीके से प्रजनन कर सकते हैं।
03. उपापचय/चयापचय (Metabolism)
  • जीवित जीव चयापचय प्रदर्शित करते हैं, जिसमें विभिन्न सेलुलर गतिविधियों के लिए पोषक तत्वों को ऊर्जा में परिवर्तित करना शामिल है।
  •  चयापचय में अपचय (जटिल अणुओं को सरल अणुओं में तोड़ना) और उपचय (सरल अणुओं से जटिल अणुओं का निर्माण) शामिल हैं।
04. समस्थैतिकता (Homeostasis)
  • बाहरी परिवर्तनों की परवाह किए बिना, जीव अपने आंतरिक वातावरण को विनियमित करके आंतरिक स्थिरता बनाए रखते हैं। इस प्रक्रिया को समस्थैतिकता या होमियोस्टैसिस के रूप में जाना जाता है।
05. आनुवंशिकता
  • आनुवंशिकता से तात्पर्य आनुवंशिक जानकारी को एक पीढ़ी से दूसरी पीढ़ी तक स्थानांतरित करना है।
  •  यह प्रक्रिया प्रजातियों की निरंतरता और स्थिरता के लिए महत्वपूर्ण है, क्योंकि यह सुनिश्चित करती है कि लक्षण माता-पिता से संतानों तक प्रसारित होते हैं।
  •  आनुवंशिक सामग्री, जो इस वंशानुगत जानकारी को वहन करती है, अधिकांश जीवों में मुख्य रूप से डीएनए (डीऑक्सीराइबोन्यूक्लिक एसिड) के रूप में पाई जाती है।
06. उत्तेजनाओं के प्रति प्रतिक्रिया
  • जीवित जीव अपने आंतरिक संतुलन को बनाए रखने या नई परिस्थितियों के अनुकूल होने के लिए बाहरी उत्तेजनाओं, जैसे पर्यावरण में परिवर्तन, पर प्रतिक्रिया कर सकते हैं।
07. वृद्धि और विकास
  • जीवित जीव समय के साथ बढ़ते और विकसित होते हैं। विकास में आकार में वृद्धि शामिल है, जबकि विकास का तात्पर्य किसी जीव के परिपक्व होने के साथ संरचना और कार्य में परिवर्तन से है।
08. विकास के माध्यम से अनुकूलन
  • विकास के माध्यम से अनुकूलन एक मौलिक प्रक्रिया है जो समय के साथ जीवित जीवों की विशेषताओं को आकार देती है।
  •  विकास किसी जनसंख्या के आनुवंशिक गुणों में क्रमिक पीढ़ियों के दौरान होने वाला परिवर्तन है।
  •  प्राकृतिक चयन अनुकूलन को चलाने वाला एक प्रमुख तंत्र है, और यह तब होता है जब कुछ लक्षण व्यक्तियों को प्रजनन लाभ प्रदान करते हैं, जिससे आने वाली पीढ़ियों में उन लक्षणों का प्रचलन बढ़ जाता है।

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