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WEEK 5: SS1 BIOLOGY THIRD TERM

          GROWTH OF MICRO-ORGANISMS Micro-organisms' growth refers to an increase in population size, i.e, an increase in t he number of cell s. Microorganisms grow and multiply by binary fission. For example, a bacterium can divide every 20 minutes and this time interval is known as the  doubling/generation time . This generation time depends on environmental factors like the availability of food, space, and adequate temperature. BENEFICIAL EFFECTS OF MICRO-ORGANISMS Many micro-organisms are beneficial in the following ways: 1.  In nature, they function as decomposers and primary producers. Many saprophytic bacteria and fungi convert dead remains of organisms and their wastes into humus , which improves soil fertility. 2.  In medicine, microbes are useful in the manufacture of drugs, vaccines and antibiotics which help in curing many human diseases e.g Penicillin - an antibiotic obtained from Penicillium   notatum  (...

WEEK 4: SS1 BIOLOGY, THIRD TERM

                                  LEARNING OBJECTIVES:  At the end of the lesson, students will: 1.  Define Culturing 2.  Describe how to prepare a culture solution 3.  List the instruments required and the necessary precautions to be taken in preparing a culture solution 4.  Demonstrate culturing and monitor the growth rate of microorganisms . 5.  Identify colonies of microbes present in different culturing samples. KEY VOCABULARY WORDS:  Culture, Agar, Microscope, Petri-dish, Inoculating loops, Hand lens, Slides etc. Culturing simply involves growing microorganisms in special media in the laboratory. It involves making sterile medium, inoculating, incubating and examining micro-organisms. By this means, micro-organisms' characteristics such as colour, the pattern of growth, and appearance can be seen. -   INSTRUMENTS REQUIRED FOR THE PREPARATION OF CULTURE SOLU...

WEEK 3: SS1 THIRD TERM, MICROORGANISMS AROUND US

 <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-8045063389507891"      crossorigin="anonymous"></script> DESCRIPTION AND GROUPS OF MICRO-ORGANISM Micro-organisms otherwise called microbes or germs can be defined as living things which cannot be seen with unaided eye but by the use of microscopes. They exist almost everywhere, in water, air, soil, surface of objects, as well as on and within living organisms.  They are carried by air currents from the earth’s surface to the upper atmosphere. They occur most abundantly where there is food, moisture and adequate temperature for their growth. It was the invention of microscope that opened the gateway to the world of these minute living organisms. The first person to discover microbes was a Dutch man called Anthony Leeuwenhoek (1632-1723). Using a simple microscope, he was astonished to discover that rain water that had been collected from pools was full o...

WAEC 2025: BIOLOGY PRATICAL MADE EASY

   WAEC CHIEF EXAMINATION REPORT WASSCE MAY/JUNE BIOLOGY PRACTICAL SOLUTIONS AND GUIDES SPECIMENS NAMES     A BEAN WEEVIL         B  BEAN SEED WITH HOLE        C WHOLE WATERLEAF PLANT .       D QUILL FEATHER .        E LONGITUDINAL SECTION OF PINEAPPLE FRUIT         F ORANGE FRUIT (Transverse section)         G RAW EGG OF A DOMESTIC FOWL .       H TEST TUBE CONTAINING 3ML OF WATER      J LONGITUDINAL SECTION OF BOILED EGG POSSIBLE QUESTIONS ON SPECIMEN A Zoological Classification: Taxonomic Rank Classification Kingdom Animalia Phylum Arthropoda Class Insecta                                       Sourced 9/05/2025: wikipedia Identify specimen A.  Answer: ...