Unit 9: Life Processes
Part 1 Microorganisms & Immunity
Viruses
• Viruses consists of
a nucleic acid
center and a
protein coat
• Wide variety of
shapes, but all are
many times
smaller than the
smallest cell
Viruses
• Viruses are considered non-living because they do not:
• Carry out metabolism
• Grow and develop
• Reproduce on their own
• Consist of cells
Viruses
• Viruses reproduce by
invading a host cell,
injecting its DNA into the
cell, and using the host cell
to produce more viruses
Viral Diseases
• Influenza
• HIV/AIDS
• Hepatitis A, B, and C
• Mumps, measles, and
chickenpox
• May be prevented with a
vaccine
• Viruses mutate rapidly,
vaccines have to be recreated
for some each year
Bacteria
• Common bacteria belong to the
Kingdom Eubacteria
• All are prokaryotic, single-celled,
and reproduce asexually
• May be autotrophic (algae) or
heterotrophic
Bacterial Reproduction – binary fission
Bacterial Shapes
• Round = coccus
• Rod = bacillus
• Spiral = spirillus
Benefits of Bacteria
• Decomposition (digestion)
• Nitrogen fixation
• Food production
• Prevent harmful infections
Bacterial Diseases
• Tuberculosis
• Streptococcus
• Tetanus
• Dental cavities
• Treated with antibiotics
• Bacteria may develop
antibiotic resistance due to
natural selection, overuse of
antibiotics lead to this
Immunity
• Immunity is your bodies ability to defend itself
against pathogens
• Pathogens include viruses, bacteria, protists,
fungi, and some animal parasites
• Your immune system also plays a role in fighting
cancer cells
Antigens and Antibodies
• An antigen is anything capable of
causing an immune response
• Most antigens are proteins on the cell
surface of microorganisms
• Your immune cells recognize
foreign antigens and create
antibodies to attack them
• Vaccines stimulate antibodies to be
produced
Active vs. Passive Immunity
• Active immunity is when your body
makes its own antibodies due to
exposure (may be life-long)
• Passive immunity is when you receive
antibodies from another source, such as
mother to fetus
Whole Virus
Vaccines
How mRNA Vaccines are made and
manufactured video clip
https://www.youtube.com/watch?v=H09Lk_MW5Dk
mRNA Vaccines
Drug Resistant TB Video
https://drive.google.com/file/d/0B0-64hmG6G_NGxwMHR4N3JTUkE/view?usp=sharing