CBSE Science 11 and 12

Q) WHAT IS FORCE?  > FORCE IS EITHER A PUSH OR A PULL.  Q) WHAT ARE THE EFFECTS OF FORCE?    > THE EFFECTS OF FORCES ARE AS FOLLOWS-    1. IT CAN MAKE A STATIONARY BODY MOVE.  2. IT CAN MAKE A MOVING BODY STOP.  3. IT  CAN CHANGE THE DIRECTION OF A MOVING BODY.  4. IT CAN CHANGE THE SPEED OF A MOVING BODY.  5. IT CAN CHANGE THE SHAPE AND SIZE OF A BODY.  Q) BY USING AN EXAMPLE EXPLAIN HOW A FORCE CAN MOVE A STATIONARY BODY? > THE TABLE STARTS MOVING IN THE DIRECTION OF THE FORCE APPLIED. THUS, A FORCE CAN SET A BODY AT REST INTO MOTION. FORCE MAKING A STATIONARY BODY MOVE   Q)  BY USING AN EXAMPLE EXPLAIN HOW A FORCE CAN MAKE A MOVING  BODY STOP? > THE FIELDER APPLIES FORCE WITH HIS HANDS TO STOP THE BALL FROM GOING FURTHER. THUS WE CAN SAY THAT A FORCE CAN MAKE A MOVING BODY STOP. Q) BY USING AN EXAMPLE EXPLAIN HOW A FORCE CAN CHANGE THE DIRECTION OF A MOVING BODY ? >  IN FOOTBALL, WE SEE THA...

Morphology of Flowering Plants Class 11 Science Notes Download in PDF-3(THE LEAF),CBSE THE LEAF THE LEAF IS A LATERAL, GENERALLY FLATTENED STRUCTURE BORNE ON THE STEM. IT DEVELOPS AT THE NODE AND BEARS A BUD IN ITS AXIL. LEAF ORIGINATE FROM THE SHOOT APICAL MERISTEM. LEAVES ARE ARRANGED IN AN ACROPETAL ORDER ON THE STEM. THEY ARE THE MOST IMPORTANT VEGETATIVE ORGAN FOR PHOTOSYNTHESIS. PARTS OF A LEAF A TYPICAL LEAF CONSISTS OF THREE MAIN PARTS: 1) LEAF BASE 2) PETIOLE 3) LAMINA LEAF BASE THE LEAF IS ATTACHED TO THE STEM WITH HELP OF LEAF BASE. THE LEAF BASE BEARS TWO SMALL LEAF LIKE STRUCTURES CALLED STIPULES. IN MONOCOTYLEDONS, THE LEAF BASE EXPANDS INTO A SHEATH TO COVER THE STEM THE PARTIALLY OR WHOLLY. SWOLLEN LEAF BASE CALLED PULVINUS IS FOUND IN LEGUMINOUS PLANTS. PETIOLE IT HELPS IN HOLDING THE LEAF BLADE, FACING TOWARDS LIGHT. LONG FLEXIBLE PETIOLE HELPS THE LEAF BLADE TO FLUTTER IN WIND. THUS COOLING THE LEAF AND BRINGING FRESH AIR TO THE LEAF SU...

Morphology of Flowering Plants Class 11 Science Notes Download in PDF-2(the stem),CBSE Morphology of Flowering Plants Class 11 Science Notes - THE STEM THE STEM IS THE ASCENDING PART OF THE AXIS OF THE PLANT. IT BEARS LEAVES, FLOWERS AND FRUITS. THE STEM DEVELOPS FROM THE PLUMULE OF THE EMBRYO OF THE GERMINATING SEED. THE STEM BEARS NODES AND INTERNODES. LEAVES ARE BORN ON THE NODES AND THE REGION BETWEEN TWO NODES IS KNOWN AS INTERNODES. STEMS BEAR BUDS WHICH MAY BE IN TERMINAL OR AXILLARY IN POSITION. STEMS ARE GREEN WHEN YOUNG AND BECOMES WOODY AND DARK BROWN LATER. THE MAIN FUNCTIONS OF THE STEM ARE- 1) SPREADS OUT BRANCHES BEARING LEAVES, FLOWERS AND FRUITS. 2) STEMS CONDUCTS WATER, MINERALS AND PHOTOSYNTHATES. 3) STEMS ALSO PERFORMS THE FUNCTIONS OF STORAGE OF FOOD,SUPPORT AND PROTECTION. 4) STEMS ALSO HELPS IN VEGETATIVE PROPAGATION. MODIFICATIONS OF STEMS STEMS GETS MODIFIED TO PERFORM OTHER FUNCTIONS APART FROM PERFORMING ITS MAIN FUNCTIONS. UNDER...

Morphology of Flowering Plants Class 11 Science Notes Download in PDF-1(THE ROOT),CBSE Introduction  • Flowering plants are multicellular organisms. • They grow by cell division • There morphological features and traits depends upon their genetic constitution. • In spite of showing such a diversity in external structures, all the angiosperm plants are characterized by presence of roots, stems, leaves, flowers and fruits. • Morphology is the study of different forms of plant organs such as roots, stem, leaves, fruits, flowers, seeds, etc. • The role of morphology is very important in the classification of plants. • In this unit we shall learn about different morphological features of plants, how different parts of plants are modified according to their particular needs which also includes defence from their enemies. • In this unit economic importance of some selected families of plants will also be discussed. MORPHOLOGY OF FLOWERING PLANTS: PARTS OF...