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water cycle in detail

​1. Global Water Distribution: The Reservoirs ​Earth’s water is constantly in motion, but at any given moment, the vast majority of it is stored in distinct reservoirs. ​Oceans (Saline): Contains 96.5% of all planetary water. ​Glaciers & Ice Caps (Fresh, Frozen): Contains 1.74% of total water; holds roughly 68.7% of all fresh water. ​Groundwater (Fresh & Saline): Contains 1.69% of total water; holds roughly 30.1% of all fresh water. ​Permafrost (Ground Ice): Contains 0.022% of total water. ​Atmosphere, Lakes, Rivers, and Biota (Fresh, Liquid/Vapor): Combined, these make up just under 0.015% of Earth's total water budget. ​2. Upward Movement: Energy Input Processes ​The water cycle is an engine powered by two primary forces: solar radiation (which heats water and drives it upward) and gravity (which pulls it back down). The upward phase changes water from a liquid or solid into an atmospheric gas. ​A. Evaporation ​Evaporation occurs when solar energy heats the surface of liq...

9th std Tissues chapter Q and A NCERT

​1. Answer Key (Revise, Reflect, Refine) ​Question 1 ​Question: Meristematic tissues divide repeatedly. What property of their cells allows them to do this?    ​(i) They have thick walls for protection.    ​(ii) They contain large vacuoles that store nutrients.    ​(iii) They have thin walls, dense cytoplasm and large prominent nucleus.    ​(iv) They are functionally differentiated cells.    ​Answer: (iii) They have thin walls, dense cytoplasm and large prominent nucleus.   ​Explanation: These cytological characteristics allow continuous and rapid cell division.   ​Question 2 ​Question: If a plant is unable to transport food from leaves to roots which tissue is malfunctioning?    ​(i) Xylem    ​(ii) Phloem    ​(iii) Epidermis    ​(iv) Sclerenchyma    ​Answer: (ii) Phloem   ​Explanation: Phloem transports food from leaves to other parts of the plant. ...