Botany lecture notes

General Characters of Gymnosperms (Lecture Notes with PPT)


characteristics gymnosperms

Gymnosperms – Characteristics
(Morphology, Reproduction and Life Cycle of Gymnosperms with PPT)

Gymnosperms are primitive seed-producing plants of Spermatophytes (Phanerogams). They are ‘Naked-Seed’ Plants. The term is derived from two Greek words: ‘gymnos’ meaning naked and ‘sperma’ meaning seeds. They are characterized by naked ovules (i.e., ovule without the ovary). The ovules of Gymnosperms are borne directly on the surface of the megasporophyls. Unlike Angiosperms, in Gymnosperms the seeds are NOT enclosed in the fruit. Thus the Gymnosperms are also known as “Phanerogams without ovary”.

seeds of gymnosperms

General Characteristics of Gymnosperms

Distribution

Ø  Gymnosperms are a small ancient group of seed plants consisting of 83 genera and 1080 species.

Ø  Distribution: Temperate and Tropical regions.

Ø  Gymnosperms were originated in the Paleozoic Era (541 – 252 million years ago).

Ø  They were the dominant plants of Jurassic and Cretaceous periods of the Mesozoic era.

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Botany lecture notes

Hydathode or Water Stomata–Structure and Functions (Short Notes)


water stomata notes

Hydathode – Water Stomata
(Structure and Functions of Hydathodes)

What are Hydathodes?

Hydathodes are specialized pores (openings) particularly present on the leaf margins, which exudes or secretes drops of water. The exudation of water as drops from the tip or margin of the leaves is called guttation. The process of guttation is facilitated by the hydathodes.

Ø  They are also called as Water Stomata because they structurally resemble stomata and they facilitate guttation (secretion of droplets of water from the pores of plants).

Ø  Hydathodes are commonly found in Angiosperms, especially in grasses.

Ø  They are also present in some other plants such as water hyacinth, balsam, roses, Hibiscus and rarely in some non-angiospermic plants.

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Zoology lecture notes and study materials

Kerala PSC HSST Zoology 2018 Question Paper + Answer Key (Q. Code 051/2018, Exam Date 19/04/2018)


Kerala PSC Zoology HSST 2018

Kerala PSC HSST Zoology 2018 Question Paper with Answer Key

Higher Secondary School Teacher: Junior
Question Paper Code 051/2018

Original solved question paper of Kerala PSC HSST Zoology Junior (Higher Secondary School Teacher Botany) examination conducted by Kerala PSC (Public Service Commission) on 19/04/2018 for the appointment of HSST (Higher Secondary School Teacher) in Zoology in Government Higher Secondary Schools of Kerala under the Directorate of Higher Secondary Education, Trivandrum, Govt. of Kerala. Question paper code: 051/2018. Questions are in MCQ (Multiple Choice Questions) format. You can download the question paper along with answer key as a single PDF file by clicking on the download link below the PDF preview. Please inform the Admin if you find any mistakes in the Answer Key.

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Botany lecture notes

Kerala PSC HSST Botany 2018 Question Paper + Answer Key (Q. Code 050/2018, Exam Date 17/04/2018)


PSC HSST Botany 2018 Answer Key

Kerala PSC HSST Botany 2018 Question Paper with Answer Key

Higher Secondary School Teacher: Junior
Question Paper Code 050/2018

Original solved question paper of Kerala PSC HSST Botany Junior (Higher Secondary School Teacher Botany) examination conducted by Kerala PSC (Public Service Commission) on 17/04/2018 for the appointment of HSST (Higher Secondary School Teacher) in Botany in Government Higher Secondary Schools of Kerala under the Directorate of Higher Secondary Education, Trivandrum, Govt. of Kerala. Question paper code: 050/2018. Questions are in MCQ (Multiple Choice Questions) format. You can download the question paper along with answer key as a single PDF file by clicking on the download link below the PDF preview. Please inform the Admin if you find any mistakes in the Answer Key.

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Biology Exam Question Papers

Higher Secondary Zoology Previous Year Question Paper (Tamil Nadu) Set 4


Plus one Plus two biology papers

Higher Secondary Previous Year Question Papers

Zoology Paper (Set 4)

HSE – TAMIL NADU

Official / Original Previous Year (Old) Question Paper of Tamil Nadu Higher Secondary Education – Zoology Paper as PDF. You can download the question paper as single PDF file for your exam preparation. To download the question paper, please click on the download link below the PDF preview. Please contact the Admin if you have any doubts.

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