Sexual Reproduction in Flowering Plants

Good morning Dear Students, Welcome to our new Academic Session 2020-2021 officially. Please mark your attendance for today. Today we will cover the following learning outcomes :- Students will be able to : 1) Draw & Explain the formation of Endosperm, Embryo & Seed. 2) Understand & Elaborate the process of Apomixis & Polyembryony. Kindly write your notes in your  register & ask your doubts in the blog itself. POST FERTILIZATION : STRUCTURE & EVENTS This includes :- i. Development of Endosperm. ii. Development of Embryo. iii. Maturation of Ovules into seed & Ovary into fruits. DEVELOPMENT OF ENDOSPERM The PEN divides repeatedly to form a TRIPLOID Endosperm. The cells contains starch, oils & proteins. Endosperm is a source of nutrition for Embryo. Types of Endosperm Formation a) Nuclear Type b) Cellular Type  , & c) Helobial Type. NUCLEAR TYPE First division & usually several of the following division are u...

Good morning class. Today we will achieve the following learning outcomes:- Students will be able to - 1) Define various outbreeding devices used by plants to prevent self pollination. 2) Elaborate about pollen pistil compatibility interactions. 3) Explain double fertilization process in plants. 4) Analyse the new plant breeding technique for Artificial Hybridisation. I will be sharing with you all at the end of explanation the YouTube video link to have better clarity of the process. Kindly write these notes in your register.          OUTBREEDING DEVICES. We know most of the plants undergoes self pollination. This could result in INBREEDING DEPRESSION in a plant species , i. e  plant decrease it pollen grain count & it may result in poor productivity of seeds. So to overcome these inbreeding depression, plants by default has developed certain outbreeding devices. Some of these devices are :- A. DICHOGAMY -  In this process plant...

Good morning dear students. First thing please mark your attendance by writing your name on the comment section. So today our learning outcomes will be : 1) To revise what ever is taught in the last two classes. 2) To reflect on topic learning by the students & also a way to help teacher access the loopholes to conquer a better way of reaching out to you all, in this new teaching learning experience. Today's Class will be divided into two blogs, the first blog will be the Revision Test & the second blog will  deal with Pollination & it's type. Time : 30 mins        TEST 1                     M. M :10 Answer the following questions according to the marks :- 1.What is pollenkit?                                     [ 1]  2. Give the ploidy of the following in Megasporogenesis :- a...

In this blog we will cover the following learning Outcomes. Students will be able to : 1. Define Pollination. 2. Explain types of Pollination involved in plants. 3. Elaborate the adaptations of plants which are pollinated by different agents. Kindly make the notes of this topic in your register. I'll be sharing in note links, self drawn diagrams & YouTube video on your official watsapp group for better understanding. POLLINATION It is the transfer of pollen grain from anther to the stigma of a pistil. This transfer is brought by abiotic agents like wind & water  or by biotic agents like animals . TYPES  OF POLLINATION. There are two types of pollination :  1. Self pollination 2. Cross pollination.        SELF POLLINATION Can occur in two types : a)  Autogamy b) Geitonogamy CROSS POLLINATION  a) Occurs through Xenogamy There are two types of flowers produced in plants Chasmo...

Good morning Children, for today's class we will do the following learning outcomes : Students will be able to : 1) Draw & Label parts of pistil. 2) Elaborate on types of ovules found in plants. 3) Analyse the structure of Megasporangium. 4) Explain the formation of Embryo Sac with diagrams. STRUCTURE OF PISTIL. We know pistil is the female reproductive part of the flower. A gynoecium may consists  of a single pistil ( monocarpellary) ormay have more than one pistil ( Multicarpellary). In multicarpellary situation pistil may be fused, then it is called syncarpous ; if pistil are free then it is called apocarpous. Each Pistil has three parts :- I. The stigma - it acts as a landing platform for pollen grains. II. Style - it is elongated tube that joins stigma & the ovary. III. Ovary - it has Ovarian cavity ( locule) . The placenta is located inside the ovarian cavity. It acts as a nutritional attachment for megasporangia, commonly called as OVULES.  T...

Today we will start with our second chapter of Unit VI. We will cover the following learning Outcomes :- I) Students will be able to draw & label the parts of a L. S section of flower. II) Students will be able to Elaborate on the structure of stamen & pollen grains. III) Students will be able to List the importance of Tapetum. IV) Analyse the mechanism of Microsporogenesis. So I will show you an image on watsapp group, where you will be asked to label the missing parts of the flower. I will expect all the students online to type the labels as I ask you all. This is just a revision quiz I want to see how many of you remember what I've taught you all in class 11. STRUCTURE OF  ANTHER We know that the male part of a flower is called stamen / Androecium. It consists of  filament, connector & bilobed anther. Bilobed anther have two theca ( layers) on it, thus they are also called Dithecous. This is a typical 3D structure of an anther. The Line of Deh...