WELCOME TO TEACHERS AND CLASS 10X2!
TEACHER: Dương Huỳnh Yến Linh
Chapter III: VIRUS AND INFECTIVE DISEASE
Lesson 29: STRUCTURE OF VIRUSES
Lesson 29: STRUCTURE OF VIRUSES
* Features of viruses
How do viruses compare to bacterial cells? (size, reproduce, made of cell)
Figure: Relative size of bacteria and virus
(B)
(A)
very small and they measured in nanometers (kích thước siêu nhỏ đo bằng nanomet)
* Features of viruses
Lesson 29: STRUCTURE OF VIRUSES
Figure:Components of virus (a) and components of bacterial cell(b)
 Viruses are not made of cells,(Virut không có cấu tạo tế bào)
Viruses are made out of two basic components: coat and core .(Có cấu tạo rất đơn giản gồm: vỏ & lõi)
* Features of viruses
 Virus need a host to reproduce  an obligate intracellular parasite (Virut nhân lên nhờ bộ máy tổng hợp của tế bào chủ  kí sinh nội bào bắt buộc)
I. STRUCTURE OF VIRUSES
 All viruses contain the following two basic components:( tất cả các virus có 2 thành phần cơ bản)
1) CORE: Genetic material/nucleic acid (DNA or RNA). (lõi: vật liệu di truyền ADN hoặc ARN)
2) COAT: a protein shell that covers the genome known as capsid (vỏ prôtêin bao bọc bên ngòai axit nucleic, còn gọi là capsid).
(core)
(Coat)
1.Viruses are compose of what?
2. What is capsid?

What is capsid?
Capsid composed of proteinaceous subunits called capsomeres,(capsit cấu tạo từ các đơn vị protein gọi là capsome)
Nucleocapsid
What is Nucleocapsid?
 Combination of the nucleic acid and capsit is called the nucleocapsid (phức hợp gồm axit nuclêic và vỏ capsit gọi là Nuclêôcapsit)
 A layer of membrane called the envelope (some but not all viruses): a lipid bilayer and protein,spikes glycoproteins (Một số virut còn có thêm vỏ ngoài cấu tạo gồm lipit kép và prôtêin,
các gai glicôprêtin.)
I. STRUCTURE OF VIRUSES
How is viral shape determined?
II. VIRAL SHAPES
How many viral shape are there?
How is each shape structured?
Helical –capsomers are arranged in a helix around the viral nucleic acid. (Cấu trúc xoắn: capsôme sắp xếp theo chiều xoắn của axit nuclêic.Ví dụ : virut khảm, virut cúm)
II. VIRAL SHAPES
The shape of the virus is determined by arranging capsid. There are three viral shapes
Polyhedral : An polyhedron is defined as being made up of 20 equilateral triangular faces arranged around the surface of a sphere.(cấu tạo bởi 20 mặt tam giác đều)
Complex: They basically consist of an polyhedral head attached to a filamentous tail. ( dạng hỗn hợp: đầu dạng khối, đuôi dạng xoắn)
VR Gây bệnh hô hấp
(VR dại)
(VR Gây đậu mùa)
(VR viêm gan B)
VR viêm gan D
(VR viêm đường hô hấp)
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
Polyhedral: 1,2,3,5,6
Complex: 6,9
Filamentous: 4,7
How Are Viruses Classified?  
Genetic material
+ DNA viruses contain DNA as their genetic material.(ex: Smallpox Chicken pox, Mononucleosis Herpes Simplex 1 (cold sores), Herpes Simplex 2 (genital herpes)
+ RNA viruses contain RNA as their genetic material (ex: HIV (Human Immunodeficiency Virus) .
Capsid structure
Helical (rod-shaped)
Polyhedral
Complex Presence or absence of a membranous envelope surrounding the capsid

* Presence or absence of a membranous envelope surrounding the capsid .
Experiment of Fraenkel-Conrat
Why did reconstructed virus belong to type A?
Protein A
ARN (A)
Protein B
ARN (B)
Compare the differences between virus and bacteria by setting “Yes” or “ No” in the tabl
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
REVIEW
Choose the best answer:
1. Viruses compose
Protein shell and DNA
Protein shell and RNA.
Protein shell, nucleic acid and envelope (some of viruses
Protein shell, RNA and envelope (some of viruses)
a
b
c
d
REVIEW
Choose the best answer:
2. How to know difference between virus and bacteria?
Not nucleic acid.
infectous.
Not made of cell
All of these.
a
b
c
d
REVIEW
Choose the best answer:
3 . Components of nucleocapsid:
Capsomeres and nucleic acid.
Capsid and nucleic acid.
Envelope and nucleic acid.
Capsid, envelope and nucleic acid.
a
b
c
d
REVIEW
Choose the best answer:
4. Capsid compose of many units. They are called
Envelope.
Nucleocapsid.
capsomeres.
Spikes glicoprotein.
a
b
c
d
REVIEW
Choose the best answer:
5, Virut không thể nuôi cấy trên môi trường bình thường như các loại vi khuẩn vì chúng:
Không có khả năng sinh trưởng.
Có kích thước rất nhỏ
Chưa có cấu tạo tế bào.
Kí sinh nội bào bắt buộc
a
b
c
d
REVIEW
Choose the best answer:
6. Viral genome is
Single – stranded DNA.
Single or double - stranded RNA.
DNA or RNA (Single or double - stranded ) .
All of these
a
b
c
d
REVIEW
Homework
- Learn and answer the question in your textbook.
- Reading lesson 30 and answer the following question:
1. How do viruses reproduce?
3. How do HIV infect?
2. How many steps are there in viral replication?
CONGRATULATIONS
Another answer !
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CONGRATULATIONS
Thanks for your listening