MONERA PROKARYOTES It includes Bacteria Blue green algae

MONERA (PROKARYOTES) It includes : Bacteria, Blue green algae

Prokaryotes (Bacteria) • General characteristics 1. Mostly unicellular 2. Nuclear membrane is absent. (No nucleus) 3. Have cell wall, not made up of cellulose. 4. Mitochondria, endoplasmic reticulum etc. absent. 5. Ribosomes present.

How small are bacteria. . ? Very small organisms consisting of single cell rarely more than 0. 01 mm in length. They can be seen only with the higher power of the microscope

What is the shape of bacteria. . ?

used for locomotion Attachment controls/determines cell structure/ function. contains enzymes that carry out metabolism protects the cell Generalized diagram of bacteria cell Cell membrane controls entry and exit of substances

How do bacteria get nutrient. . ? Autotrophic bacteria : Few species of bacteria can build up their food by photosynthesis. Others heterotrophic bacteria produce & release enzymes which digest the food outside the cells. Digested food then absorbed back into the bacterial cell

How do bacteria reproduce. . . ? By binary fission. In the bacterium, the nucleus divides and then the cytoplasm is shared between the two cells. Time: 20 -40 minutes.

V I R U S Viral disease What is virus. . . . ?

Virus is a particle, not considered to be a cell. . Why. ? The virus particle contains no cytoplasm, no cell membrane and no nucleus.

How small is virus…? Virus is extremely small (nm). (to smaller than bacteria) Viruses are only visible under electron microscope.

VIRUS: STRUCTURE Do not have typical cell structure. It contains nucleic acid and protein coat. 1. Nucleic acid : DNA/ RNA 2. Coat is made up of capsid (protein coat)

How do virus reproduce. . . ?

Classification of virus. . . ? Classification of virus in living organisms is debatable. Why? 1. Viruses do not feed, respire, grow, excrete, move or respond to stimuli which are characteristics of living organisms. 2. They do reproduce but only by rearranging their host’s cytoplasm.

FUNGI

FUNGI : General characteristics 1. Eukaryotic cell structure 2. Mostly multicellular. 3. Cell wall present which is made up of chitin. (not cellulose) 4. Heterotrophic nutrition (do not have chlorophyll in the cells)

FUNGUS: STRUCTURE HYPHAE The main body of a fungus is the mycelium, which is made of hyphae.

How do fungus get their nutrient. . ? From where does this fungus get nutrients. . ? Most fungi get their nutrients from dead organic matter. How. . ? The hyphae secret enzymes into dead organic matter and digest it to liquid products. The digested products are then absorbed back into the hyphae. (Saprophytic )

How do fungus get their nutrient. . ? From where does this fungus get nutrients. . ? Some fungi get their nutrients from living plant/animal tissue. How. . ? The hyphae penetrate the tissue of their host plant and digest the cells and their content. (Parasitic )

How do fungus reproduce. . ? Fungus reproduce by releasing microscopic, single celled spores.

Identify. . . ? Given figure shows a scanning electron micrograph of Penicillium (fungus). Identify the labels. B A