Biology Notes - Document 6.pdf

# Plazmidy - Where they are found : prokaryotes (bacteria, some blue-green algae and yeasts) - What they are : additional genetic information - What they are used for : transferring genes through conjugation - carry genes that are not necessary for survival. # Bacteriophage - Viruses that a...

# Plazmidy - Where they are found : prokaryotes (bacteria, some blue-green algae and yeasts) - What they are : additional genetic information - What they are used for : transferring genes through conjugation - carry genes that are not necessary for survival. # Bacteriophage - Viruses that attack bacteria # Photoautotrophic - Obtain energy from light and use it to produce their own food. # Conjugation - A process in which two bacteria exchange genetic material # Water Bloom - Rapid growth and multiplication of algae or blue-green algae on the surface of water. # Nukleoid Function: - Storing DNA - Controlling cellular processes # Ribozom Function: - Synthesizing proteins - Creating proteins # Describe 1 shared feature of all viruses and viroids - Both are infectious # What is the difference between a virus and a viroid? - **Virus:** contains either DNA or RNA - **Viroid:** contains only RNA # What happens to a virus after entering the lytic cycle? - The virus enters the cell and injects its genetic information. - It takes control of the cell. - Viral particles assemble and create new viruses. - The cell is destroyed - the cell bursts and the new viruses are released to infect other cells. # Importance of Blue-Green Algae: - Water purification - Habitat for organisms - Production of oxygen through photosynthesis. # Ribosome - Small cellular structure responsible for protein synthesis - It joins amino acids according to mRNA sequence information. # Capsid - Protective protein coat - Surrounds and protects the nucleic acid (DNA or RNA for viruses) - Helps in transfer to host cells. - Protects nucleic acid from damages (e.g. UV radiation,enzymes) - Helps the virus recognise and attach to the host cell # Endosymbiosis - It explains how some cell organelles were created. - For example, mitochondria and chloroplasts) - Theory states that bacteria were engulfed by a cell and formed a symbiotic relationship with the host cell, eventually becoming integrated as part of the cell. # Retrovirus - Type of virus that contains genetic information in RNA format and can transcribe it into DNA. - When entering a host cell, the RNA is transcribed into DNA - The retroviral DNA is integrated into the host cell's DNA. - The virus starts replicating along with the host cell. - Example: HIV # Bacterial Diseases - Pneumonia - Sore throat - Urinary tract infections - Tuberculosis - Tetanus - Boreliosis - Plague # Viral Diseases - Influenza - Common Cold - COVID-19 - HIV/AIDS - Mumps - Warts - Hepatitis # Bacterial Cell - Flagella - Fimbriae - No thylakoids (membrane structures) # Blue-green Algae Cell - Photosynthesis - Contain Chlorophyll - Have thylakoids # What happens to a virus that enters the lysogenic cycle? - The viral DNA becomes incorporated into the host cell's DNA. - **Inactive** - The virus becomes a prophage. - The virus remains inactive, does not damage the cell and does not multiply. - The cell grows and divides, and the viral DNA is copied. - **Active** - The virus becomes active after exposure to stress, UV radiation, or chemical factors.