Nucleic Acid Functions Flashcards
What are the Nucleic Acid Functions?
- Determine what characteristics livings things have.
- Direct protein synthesis within the cell.
- Energy carrier within the cell.
Nucleic Acid Structure
- Monomer is called a nucleotied
- Made up of phospate sugar, and nirtogenous base.
Nucleic Acids in DNA
Polymer can B:
- RNA - ribonucleic acid
–> single strand of nucleotides
–> each nt contains ribose sugars
- DNA - deoxyribonucleic acid
–> double stranded nucleotides
–> each nt contains deoxyribonucleic acid
4 diff nucleotides…
DNA - adenine, guanine, cytosine, thymine.
RNA - adenine, guanine, cytosine, uracil.
Viruses do not fit into the kingdom system if…
- they show few characteristics of living cells
- they need to be in living cells (host) to survive and reproduce
Charateristics of livings things:
- reproduction
- growth
- metabolism
- DEATH
- Adaptation
- Response to stimuli
- Locomotion
General features of a virus
- Very small, 20 to 400 nm in size
- Consist of an inner nucleic acid (DNA or RNA) core
- Comes in various shapes
Structure of a virus
Core: Nucleic Acid (RNA or DNA) –> Genome
Shell: Protein coat –> Casid
Metric Units
Virus’s specificity
- Each virus has a specific group of host that is can infect.
- This is called the host range.
- Host range can B broad or very narrow.
Recall: “Spikes” –> help a virus attach to host cells.
The reproduction Cycle of a Virus:
- Attachment/ Entrance
Attachment/ Entrance
- Virus is in contact w host cell
- The v is taken in by phagocytosis or the v injects genome into cell.
- The v releases DNA or RNA into the cell.
Synthesis
- The DNA or RNA takes over the protein cat synthesis of the cell.
–> The v uses the cell’s materials (ATP, enzymes, can cell parts) to replicate it’s own nucleic acid (genome and make new protein coats.
Assembly
Viruses assemble:
(nucleic acids + protein coats combine)
Release
Virus R realized from the cell.
(Release of many v ruptures the cell membrane, causing death – lysis)
Types of Replication cycles
Lytic cycle - V infects host n makes more v
Lysogenic cycle - v coexist w cell (v remains dormant)
Explain the Lytic cycle
Explain the Lysogenic cycle
Types of v
- DNA v
- RNA v
—> subgroup of RNA v is called retroviruses
What is the DNA V all about and their examples?
- Genome is double stranded
–> Mutations R minimal
–> it maintains its identity! - Therefore, ur immune system will always recognize the V
- Can carry out Lysogenic cycle
– it remains dormant in the nucleus of host cell.
Examples:
1. Human Papilloma V
–> Warts, development of cancer (ie cervical)
- Herpes V
–> cold sores - Varicella-Zoster V
–> Chicken Pox - Epstein- barr V
–> Mononucleosis
What is RNA V about and what are their examples?
- Genome is single stranded
–> mutation can B a permanent change - Therefore, UR immune system may not recognize the new mutated V
–> New anti-bodies need to B made - Can NOT carry out Lysogenic cycle
–> This would need DNA to remain dormant in the nucleus of the host cell.
Examples:
1. Rhinoviruses (common cold)
–> Infect respiratory system
- Influenza (The Flu)
–> Infects cells of the respiratory tract - Rotavirus (stomach Flu)
–> Gastrointestinal problems
–> such as severe diarrhea
What is Subgroup: Retrovirus about and what are their examples?
Contain and enzyme (reverse transcriptase) that allow them to convert their RNA to DNA.
–> Therefore, able to carry out the Lysogenetic cycle
- Can mutate + lay dormant within host cell
–> therefore, R more dangerous than some DNA v + non - retro RNA V.
Examples:
1. Human Immunodeficiency V (HV)
–> infects T-cells of the immune system.
- Hepatitis B
–> infects liver cells.
Viruses n human health?
- Many diseases R caused by V
- Destructions of host cells causes by symptoms of disease.
- Vaccines R used to prevent many viral infections.
What is a Vaccine?
- Vaccines contain non-infectious virus particles.
- This causes the body to react and make antibodies against the v.
- The body is now ready to fight infection by the REAL v!
Viruses n human health?
- Many diseases R caused by V
- Destructions of host cells causes by symptoms of disease.
- Vaccines R used to prvent many viral infections.
Are vaccines important?
- Create a “wall” against V
- Breaks the path of transmission:
–> V is unable to infect cells
–> V is unable to make copies of itself - Therefore, V is unable to infect other hosts
What is a herd immunity?
- If most people of a populated area get vaccinated, then individuals unable to get the shot R also protected!!! = PROBLEM parents R not choosing to vaccinate their kids due to “fears”.
What do antibiotics do?
- They do not kill V!!!
- Antibiotics target organelles…
–> DO NOT KILL V!!!!!!!
ANTI - Viral Drugs: How do they work?
Actions:
1. Prevent attachment to host cell.
2. Block entry into host cell.
viruses n Biotechnology
- useful tools 4 genetic engineering
–> can B used to transport a “gene of interest” into a host’s cells genome.
