Student: Faith Karngar Student #: L200109160 01 QUESTIONS [1]Write about the characteristics of viruses and their replication cycle. [2]Differentiate between virions, viruses and viroids. [3]Differentiate between eukaryotic and prokaryotic mircroorganism and write characteristics of fungi [4] Write down the characteristics of yeaast, their beneficial and harmful effetcs on human [5] Compare the characteristics of mold and yeasts in their propagation methods [6] Mold beneficial and harmful effects on humans, types of sexual spores and specialized form of hyphae [7] How did Louis Pasteur’s swan neck experiment performed and what its significance [8]What is koch’s postulates and for what purpose they are used ? 02 Characteristics of viruses 1 Non living structures.. 2 Non-cellular.. 3 Contain a protein coat called the capsid.. 5 Have a nucleic acid core containing DNA or RNA (one or the other - not both) Capable of reproducing only when inside a HOST cell.. 03 Virus replication cycle Attachment Penetration Uncoating Replication Assembly . Maturation Release . 04 Difference between virus, virion and viroids Virus virus •Virus is a small entity consist of either DNA or RNA as genetic material. •Genetic material is enclosed by protein coat called capsid. •Virus may or may not surrounded by outer lipid membrane called envelope. Virus infect all types of organisms. Virion Virion 1. Virion is a complete functional virus that has the capacity to infect living tissue. 2. It includes the genetic material either RNA or DNA, capsid, envelope and membrane proteins. 3. Membrane proteins allow the virus to bind to its host and enter it Viroids Viroid Viroid is smaller than virus. 2. Viroid is single stranded covalently closed infectious RNA molecule without capsid. 3. They replicate by RNA-RNA transcription and lack protein coding. 4. Viroids only infect plants. 05 Difference netween prokaryotic and eukaryotic microorganism and the characteristics of fungi Prok aryotes are always unicellular, while eukaryotes are often multi-celled organisms. Additionally, eukaryotic cells are more than 100 to 10,000 times larger than prokaryotic cells and are much more complex. The DNA in eukaryotes is stored within the nucleus, while DNA is stored in the cytoplasm of prokaryotes. Fungi are eukaryotic, non-vascular, non-motile and heterotrophic organisms. They may be unicellular or filamentous. They reproduce by means of spores. Fungi exhibit the phenomenon of alternation of generation. Fungi lack chlorophyll and hence cannot perform photosynthesis. 06 Characteristics of yeast , their beneficial and harmful effects on humans Yeast Yeasts are single-celled microorganisms and are members of the Kingdom Fungi. Yeasts are then further classified based on the characteristics of their cell, ascospore and cellular physiology.. Beneficial effects of yeasts on humans 01 Yeast are single celled Yeast grows by fermentation 03 02 yeast is widely dispersed in nature Yeast reproduce asexually Yeast keeps your digestive system healthy and in balance. The right amount in your body helps your immune system do its job. Yeast is part of a healthy mix of bacteria in your gut. It can help you absorb vitamins and minerals from your food, and even fight disease harmful effect on humans 04 Too much yeast can trigger diarrhea or a skin rash. It's rare, but if yeast overgrows and gets into your blood, it could cause infection throughout your whole body.A 07 Compare the characteristics of mold and yeast in their propagation methods Mold Mold is a fungi that contains multiple identical nuclei. It grows in the form of hyphae of filaments. Mold has a fuzzy appearance and can be an orange, green, black, brown, pink or purple in color. Can be found in several shapes. Typically found in damp, dark or steam-filled areas.Some molds are used in food production, for example, Penicillium is used in the production of cheese, Neurospora in the production of oncom, which is made from the by-product of tofu. Reproduce through small spores, which can be either sexual or asexual. Secrete hydrolytic enzymes that degrade biopolymers such as starch, cellulose and lignin into simpler substances that can be absorbed. Can cause allergic reactions and respiratory problems 1000s of known species, including penicillium. 1500 known species – 1% of all fungi. Nature looks back at us; A peach with mold staining magnify Nature looks back at us; A peach with mold staining VS Yeast A type of fungi that contains only a single cell White and thready. Usually oval in shape.Very common. Can be found on fruit and berries, in the stomachs of mammals and on skin, among other places. Ethanol production, baking, vitamin supplements, study of cell cycle. Most reproduce asexually through mitosis. Most common form called “budding.” Convert carbohydrates to alcohol and carbon dioxide in anaerobic through fermentation. Also obtain carbon from hexose sugars. Can cause infection in individuals with compromised immune systems. 1500 known species – 1% of all fungi. Nature looks back at us; A peach with mold staining magnify Mold harmful and beneficial 08 effects on humans , types of spores and specialized form of hyphae benefits types of spores When controlled and harnessed, mold can be used for good, including several medicines besides penicillin. It's also used to produce cheese, soy sauce, cured meats and other foods. Otherwise, it's always a safe bet to assume that a mold infestation in your home or business poses serious health risks. Some people are sensitive to molds. For these people, exposure to molds can lead to s ym pt om s s uc h as s tuf f y no s e, wheezing, and red or itchy eyes, or skin. Some people, such as those with allergies to molds or with asthma, may have more intense reactions. danger Gymnosperms and angiosperms form two kinds of spores: microspores, which give r is e to m ale gam etoph ytes , and m egaspores, which produce fem ale gametophytes. Nutrient Absorption from Soil Some fungal species (e.g., mycorrihizae) have developed a symbiotic relationship with vascular plant species. The fungi forms specialized hyphae called arbuscules, which can be found in the roots or phylum of vascular plants, and function to absorb nutrients and water from the soil specialized hyphae 10 Louis pasteur swan neck experiment and its significance Louis Pasteur devised the experiment illustrated above. He heated an infusion sealed in a vessel with a S-shaped or "Swan neck", let it cool, and then broke of the tip of the vessel. This allowed fresh air to enter, but any particulate matter was trapped in the bend of the neck.e. Once it was understood that these micro organisms (germs) exist, carry and spread disease it was possible, to an extent, to prevent them from doing so. Pasteur had finally identified wh a t c a u s e s i n f e c t i o u s disease and why it spreads.. What is koch postulates and for what purpose are they used? Koch's postulates are four criteria designed to establish a causal relationship between a microbe and a disease. The postulates were formulated by Robert Koch and Friedrich Loeffler in 1884, based on earlier concepts described by Jakob Henle, and refined and published by Koch in 1890. Molecular Koch's postulates are a set of experimental criteria that must be satisfied to show that a gene found in a pathogenic microorganism encodes a product that contributes to the disease caused by the pathogen. Genes that satisfy molecular Koch's postulates are often referred to as virulence factors. THANK YOU!
