Fungi |Characteristic Features of Fungi |Mode of Nutrition in Fungi | Mode of Reproduction in Fungi

Fungi |Characteristic Features of Fungi |Mode of Nutrition in Fungi | Mode of Reproduction in Fungi

You would have seen fungi as a white layer on bread when you leave it outside at room temperature for quite a few days. Fungi get favourable conditions & therefore they grow. But, the same bread when kept inside a refrigerator remains fresh for a longer period of time. Fungi are multicellular e. they are made up of multiple cells They are Heterotrophic (Depend on others for their food). They live in colonies and prefer warm & moist places to grow. They are immobile. Some common examples of fungi are: Yeast, Mushroom, Molds. 1. Organisms of kingdom Fungi have the capacity to become multi-cellular, at some stage of their lives. Some are uni-cellular.

They are Eukaryotic.They have cell walls made up of tough complex sugar called “chitin”.Some of these organisms use decaying organic material as food, so they are called “saprotrophs”. Some require a living protoplasm of a host organism for food, they are called “parasites”. Examples: Yeasts (unicellular), Moulds, and Mushrooms. Some fungal species live in permanent, mutually dependent relationship with blue-green algae (cyanobacteria). This relationship is called as “symbiosis”, and the symbiotic life forms are called “litchens”. We can see litchens as the slow growing, multi-coloured patches on the barks of the trees.

Characteristic features of fungi

Fungi are unicellular or multicellular and filamentous. All fungi are made up of fine threads called hyphae. Fungi are plant like organism. They have cell wall.They lack chlorophyll and that’s why do not perform the process of photosynthesis. Store food in the form of glycogen instead of starch. Examples of fungi are yeast, moulds such as Penicillium, bread mould and aspergillus, mushrooms etc. Study of fungi is called mycology.

Habitat of fungi

Fungi are present everywhere and in any habitat. They are found in deserts, cold regions, sea waters, fresh water, in soil, on plants and animals, human skin etc. They grow best in dark warm moist places.

Mode of nutrition in fungi

Fungi look like plant but they cannot make their own food. Fungi are heterotrophic i.e. they depend upon another organism for their food. Fungi generally follow saprophytic or parasitic mode of nutrition. Saprophytic fungi obtain their nutrients from non-living organic matter, usually dead and decaying plants and animals matter by absorbing soluble organic compounds. Parasitic fungi live in or on other organism and get their nutrients from their host. It generally causes disease or illness to the host.

Mode of reproduction in fungi

The Reproduction of fungi can be either sexual or Asexual. In asexual mode of reproduction fungi reproduce by Fragmentation, Budding. Produces spores. The majority of fungi reproduces asexually.

Advantages of fungi in day to day life and it’s usage

Fungi are decomposers, they are good for the soil and cleaning up the environment. Many fungi are used for the production of antibiotics. For example Penicillium is a fungus which produces antibiotic call penicillin. All mushrooms, including the ones we eat, a large fungi. Yeast is another useful fungus which is used in many fermentation processes.

Disadvantages of fungi

Many saprophytic fungi spoil our food, clothes, leather articles etc. example you me have noticed the cottony growth on leather or stale bread. Eating such food can make you ill. Many fungus can cause human diseases.

Some fungal species produces toxin that affects plants animals and humans.

THANK YOU

NANDITHA AKUNURI

Algae | Structure of Algae | Mode of nutrition in Algae | Types of Algae

Algae | Structure of Algae | Mode of nutrition in Algae | Types of Algae

Class -VIII Biology

Algae are unicellular or multicellular:

They are multicellular i.e. Made of multiple cells. They prefer mostly aquatic habitats. Some common examples of protozoa are: Spirogyra, Ulothrix, Chlamydomonas

Structure of algae: Some algal cell join each other to form filaments and some have branches or fronds. Both unicellular and multicellular algae live as individual or in colonies. Algae is being found in different forms, Unicellular forms, Multicellular forms A colonial form- volvox.

Unicellular forms:Examples of unicellular Algae are as follows—

Chalamydomonas: It is a green single Cellular alga. They are generally oval, spherical or peared shape. Flagella is used for locomotion.

Habitat of algae: Algae live mostly in an aquatic environment floating on the water. Many times they are found in ponds, lakes and seawater. Some algae leave on bark of tree and some on moist soil and rocks. Some Algae are also found in snow and some in hot spring.

Mode of nutrition in Algae: Algae are considered autotrophs as all of them have chlorophyll in it. Most Algal groups are considered photoautotrophs, they depend entirely upon their photosynthetic Apparatus for their food production, using sunlight as a source of energy and CO2 as a source of carbon to produce their own food. Many of the algae have a symbiotic relationship with plants and animals.

Types of Algae

On the basis of the pigment found cell they are classified into following groups

Blue green Algae: They have blue pigment along with chlorophyll. Nucleus is not present in blue green algae. They are more like bacteria. And therefore they are called as Cyanobacteria. They live in freshwater.

Green algae: This contains mainly chlorophyll. They live in freshwater. Green algae (singular: green alga) are photosynthetic algae that are characterized by having chlorophylls a and b as the predominant pigments, thus rendering them green in colour. They store food as starch within plastids. They include the chlorophytes and the charophytes.

Brown algae: Contents brown pigment in addition to chlorophyll. Brown algae generally marine. Many seaweeds are brown algae, which are almost 50 to 60-meter long.

Red algae: Contains red pigments besides chlorophyll. Red algae are generally marine. Red algae, or Rhodophyta, are one of the oldest groups of eukaryotic algae. The Rhodophyta also comprises one of the largest phyla of algae, containing over 7,000 currently recognized species with taxonomic revisions ongoing.

Uses of Algae: Algae are the major source of food for fishes, prawns and many aquatic animals. Sea Algae is eaten in many countries. Most of the oxygen in the atmosphere is released by algae. Red algae yield algin, substance used to thicken cosmetics and food items like ice cream, jelly coma chocolates. Agar a solidifying substance obtained from red algae used in microbiological research. Algae also consumes huge amount of carbon dioxide which is good for our ecosystem.

Disadvantages of Algae

Algal blooms can be toxic and it harms aquatic ecosystem and human health.

THANK YOU

NANDITHA AKUNURI

PRTOZOA | AMOEBA | EUGLENA | CLASS 8 | MICROORGANISMS | CBSE

PROTOZOA

CLASS- VIII

BIOLOGY

Protozoa are single-celled microscopic organism. Protozoa are heterotrophs i.e they don’t produce their own food. They generally feed on organic matter such as other microorganisms or organic tissues and debris. Protozoa are heterotrophic microorganisms which do not fully plant or animals.

Why protozoa were considered animals?

Protozoa are unicellular microorganisms which do not fully dissemble plant or animals. The word Protozoa means “early animals” . Earlier Protozoa were consider as animals as they do not have cell wall and they can move. Apart from few examples of protozoa which contains chlorophyll are either saprophytic and parasitic. the protozoa which contains chlorophyll lack other plant characters.

Habitat of protozoa

protozoa freshwater, saline water, ponds , lakes, dirty water drains, rivers, sea water and also in damp soil. Some parasitic protozoa so live in the bodies of other organisms including human beings. Examples of protozoa Giardia, Amoeba, Paramecium, euglena etc.

How Protozoa can move and feed themselves?

The most important characteristic of protozoa is that they can move from one place to another.

Examples

Amoeba:- Amoeba is a single cell organism looks like mass of Protoplasm with no fixed shape. It can move in any direction by extending pseudopodia. Pseudopodia is also called as false feet. A pseudo podium is formed by the flow of Protoplasm in the direction of movement. Pseudopodia helps Amoeba in feeding. It extends to encircle the food particle which is then taken in by the cell and digested. Amoeba feeds tiny algae and bacteria.

Paramoecium

This slipper shaped protozoan which lives in ponds and ditches swims by beating it’s Cilia against water. Movement of Cilia helps to direct food and water into an oral groove in paramoecium. Paramecium feeds on small algae and bacteria. Waste matter of paramoecium is thrown out through an anal pore.

Euglena

Euglena is found in ponds, ditches and other stagnant water bodies.

The body of euglena is spindle shaped slightly elongated and tapers at the top.One end of euglena has flagellum which they use to move from one place to another. Some euglena has two flagella. Euglena with chlorophyll normally obtain their food through photosynthesis. Euglena which lives in dark condition ingest food particles through a mouth like opening leading to a gullet. This organism has characteristics of both plants and animals. Euglena contains chlorophyll and that’s why most of them autotrophs. Even euglena has chlorophyll and live as autotroph it doesn’t come under plant Kingdom because they don’t have cell wall. Some euglena don’t have chlorophyll and live as saprophytes or parasites.

Advantages of protozoa

Saprophytic protozoans benefit the environment by decomposing organic matter in the soil. Parasitic protozoans prey on bacteria and algae helps to regulate the population of bacteria and algae.

Disadvantages of protozoa

Many protozoa are parasites and causes many diseases.

Diseases like dysentery and malaria are caused by protozoa. For example entamoeba causes amoebic dysentery.

Protozoan name plasmodium causes disease malaria inhumans. Plasmodium is commonly known as malarial parasite.

THANK YOU

NANDITHA AKUNURI