This document contains information about a presentation on botany that a student named Morsheda Nur Tisha is preparing for a higher secondary class. It includes sections on microbiology, types of microorganisms, characteristics of living organisms, viruses, the structure and replication of viruses, bacteria, the structure of bacteria, and the economic and biological importance of viruses and bacteria.

1. Noakhali Science & Technology University
Department Of Education,Year-2,Term-1
Subject-Botany-1
Course code-EDN-2108
Direct in response on 2nd incourse
Topic-Making a presentation over botany subject for higher secondary
class as a teacher
Submitted by
Name-Morsheda Nur Tisha
Department Of Education
Roll-BKH1919033F
Submitted to
Name: S.M. Mushfiquer
Rahman Ashique
Lecturer
Department Of Education

2. Microbiology
• Microbiology, study of microorganisms, or
microbes, a diverse group of generally minute,
simple life-forms that include bacteria, archaea,
algae, fungi, protozoa, and viruses.

3. Types of microorganisms

4. WHAT ARE THE CHARACTERISTICS OF
ORGANISMS?
1. All living things are composed of cells
2. All living things perform certain
chemical processes such as growth
and digestion
3. All living things can reproduce
4. All living things either make their
own nutrients or ingest nutrients
from the environment
5. All living things respond to stimuli
such as light and touch

5. Virus
A virus is a non-cellular particle made up
of genetic material and protein that can
invade living cells and reproduce.
– Causes infections in ALL life forms

6. What are viruses
• Infectious agents, NOT CELLS
• No nucleus, organelles,
cytoplasm
• Can replicate ONLY inside a
living cell
– Obligate Intracellular Parasites
• Contain only 1 type of genetic
molecule, either DNA OR RNA
• Do not grow
• NOT ALIVE
• Some viruses have:–
Envelop – lipid rich layer
outside protein coat
• Envelop may have proteins
that help infect cells
• Ex. HIV, Flu
• Can use presence or absence
of envelop to classify
– Tails
– Spikes
– Legs

7. Living characteristics
• Every virus is made of either DNA or RNA and protein.
• They can reproduce inside the living cells.
• Like pathogenic bacteria, it also cannot live without living cells.
• Genetic recombination is found to occur in this.
• Mutation is found to occur.
• They have genetic objects.
• They can grow and can increase within host cells
• There are specific races or strains
• They can be transmitted from one host to another.
• They are capable of multiplication in the host.
• They exhibit mutations
• They show irritability because they react to heat, radiation, and chemicals.
• They are capable to reproduce and hence can increase their number.
• They are resistant to antibiotics.

8. Nonliving Characteristics
• It has no distinct cell.
• An individualist virus cannot make am organic activities without living on another living cell.
• They have no cytoplasm, nucleus and another cell organizes and metabolic enzymes.
• Crystal granules can be made.
• They don’t contain both RNA and DNA together.
• They lack metabolic activity outside the living cells.
• They lack ribosomes and cellular enzymes necessary for nucleic acid and protein synthesis.
• They have a lack of cell membrane and cell wall.
• Don’t undergo their own metabolism and no motility
• No energy conversions and no reactions to stimuli
• No reproduction outside living cells
• They can be crystallized and can be precipitated
• The outside of the cells act like inert chemicals
• They don’t show growth, development, nutrition, reproduction, etc.
• Can’t grow in size, shape or something like that. Don’t possess any sort of nutrients.

9. SIMPLE (GENERAL) STRUCTURE
• The general structure of
most viruses is a simple
protein, outer coat, called a
capsid which encloses
nucleic acid (either DNA or
RNA). There are genes
located on the nucleic acid
but there numbers are small
compared to complex
organisms.

10. RNA VS DNA

11. Replication of Virus
• Viruses are obligate
parasites. They can only
function by using the energy
of their hosts. In order to
replicate themselves they
must use the structures and
energy of the host they have
occupied.
• The chart below shows the
replication of a
bacteriophage. This virus
infects bacteria. It takes
about 30 minutes to complete
its replication cycle.
STAGES OF VIRUS REPLICATION
A virus will replicate many times when it invades a
host cell. There are 4 stages involved in this process:
1. Attachment: The virus attaches to a host cell. In
the case of the bacteriophage it will attach to a
bacterium.
2. Entry: The virus forms a hole in the membrane or
cell wall of the host. The nucleic acid of the virus
enters the host cell.
3. Synthesis: The virus’ nucleic acid is used to make
new viral nucleic acid and proteins for the new
viruses being produced. (The host cells’ DNA
becomes deactivated.(
4. Assembly: New viruses are made inside the host
cell.
5. Release: The host cell bursts to release the new
viruses. The bursting is called lysis.

12. Animation of replication process

13. Lytic cycle Lysogenic
cycle

15. QS:Is virus smaller than bacteria?
• Viruses are tinier than
bacteria.
• To see bacteria we use light
microscopy (400x
magnification?). Viruses can
only be viewed using an
electron microscope.
• Virus is 10–100 times
smaller than bacteria.
• Virus can stay inside the
bacteria.
• In fact the largest virus is
smaller than the smallest
bacteria.

16. QS:Economical & Biological importance of Virus
Useful roles:
• In preparing antidotes/vaccine: Pox, mumps, polio, jaundice etc diseases can be
controlled by penetrating using or dead virus in the human body as vaccines.
• In controlling harmful animals and insects: Some animals and insects which are
harmful to humans can be controlled by some special virus.
• In the laboratory: Virus is used in the lab, as the simplest living model. In the
research of genetics, the virus is used mostly. It is an important subject in genetic
engineering.
• In the evidence of evolution: Virus plays a vital role to acquire knowledge about
the trend of evolution and the process of formation of living organisms because the
virus contains both living and non-Living characteristics.
• In nanotechnology, viruses can be considered as organic nanoparticles. Because of
their size, shape, and structures have been used as a template for organizing
materials on the nanoscale.

17. Harmful roles:
• Different diseases like common Cold, Influenza, Mumps, Pox,
Polio, Yellow fever, Harpish, Aids etc. are caused by the
attack of the virus.
• Human viruses, especially those that caused to deaths, can
have larger negative economic effects. For example, Africa’s
Ebola virus occurred in economic losses of over $1.6 billion.
• The virus destroys plenty of bacteria which useful for
humans.
• Viruses can cause a destructive influence on human societies.
They can be weaponized for biological warfare.
*QS:What is retrovirus?-A retrovirus is a type of virus that
inserts a copy of its RNA genome[a] into the DNA of a host
cell that it invades, thus changing the genome of that cell.

18. Bacteria
WHAT ARE PROKARYOTES?
 Most microbes are prokaryotes
 Exist almost every where on
earth
 Cells that do not have a nucleus
 Contains a rigid cell wall,
cytoplasm and ribosomes.
 Identifying Prokaryotes:
Cell Shape
Cell Wall
Movement
What is Bacteria?
Bacteria are unicellular
prokaryotic
microorganisms.
They are prokaryotes: they
have no nucleus and no
organelles with membranes.

19. Classification of Bacteria-According to
structure:

20. Structure of a typical Bacterium

21. QS:Importance of Bacteria
For environment:
1.Natural scavengers:
2. Nutrition: They are an important source of vegetative
nutrition in the marine environment.
For plants:As a source of manure (fertilizer enhancers).
For humas & animals:Bacteria like Entero-coli live in the gut
intestines of animals in a symbiotic fashion. They are friendly
bacteria helping in degradation of unused food and help in its
expulsion from the body.Some bacteria like E.coli which are
present in the body resist the growth of harmful bacteria like
typhoid.
For medical:1.For antibiotic production 2. For the production
of vaccines. 3. For genetic engineering

22. Negative impacts:
• Bacteria like the Salmonella can cause
diarrhea in humans. 90% of the
gastrointestinal infections we suffer are
caused by ingestion of food infested with the
negative kind of bacteria. Escherichia coli,
proteus or Klebsiella in extreme doses are
harmful and can also spoil food .
Diseases caused by
Bacteria: Tooth
decay,Lyme
disease,Tetanus,Tuber
culosis,Pneumonia,Chol
era