Cells - prokaryotic

Prokaryotic Cell

organism without a membrane boudn organelles

tyoes of prokary

bacteria and archaea

ex of bacteria

e coli, chloera, cyanobacteria

List of prok structures

cell wall, capusle, cell membrane, dna, plasmids, cytoplasm, ribosome, mesosome, 

description of structures… dna

aka the nucleoid/genophore

free in cytoplasm

description of structures… plasmids

small circular pieces of DNA that contain genes that can be passed from one bacterial cell to another

description of structures… cytoplasm

same as in eukaryotic cell

contains cystol (where everything is suspended in it)

description of structures… ribosome

translate mRNA to protein, ribosomes are smaller in pro

description of structures… mesosomes

infoldings of cell membrane, unclear function but involved in respiration and DNA attachment and replication 

description of structures… cell wall

made of peptidoglycan aka polymer of amino acids and sugagrs

be able to label a prokary

slime capusle function

protects bacteria from virsuses/attacks from host immune system
hides antigens on cell surface

slime capusle description

made of polysacc

contains water to protect against disiccation/drying out

how does bacteria share info

contains several plasmids. plasmids are replicated independently of bacteria DNA during bacterial conjugation and may get a advantage like a resistance

plasmids often used for

engineering to make copies of genes or large amounts of proteins or horomones

WHy would a thicker capusle be more likely to surivive

Capusles that are thicker are less likely to bind to meurin,

Why are virsuses not considered living?

• no metabolic reactions

• cannot move independently

• no organelles

virsuses are

acellular

Why are antibiotics ineffective against viruses

bc they do not have bacterial structures

name 2 structures found in all bacteria that are not in plant cells

1. mesosome

2. meurin cell wall

bacteria cell wall

made of meurin

What is a virus

A virus is a microscopic infectious agent that can only replicate inside living cells. It is acellular and not considered a living organism

What are the key structural components of a virus?

• Genetic Material: DNA or RNA, single or double-stranded

• Capsid: Protein coat protecting the genome

• Envelope (optional): Lipid layer from host cell membrane

• Attachment Proteins: Surface proteins for host cell binding

• Enzymes (optional): e.g., reverse transcriptase in retroviruses

Why are viruses considered acellular

They lack cellular structures like a nucleus, ribosomes, and organelles. They do not carry out metabolic processes independently

How do viruses replicate?

• Attachment to host cell via specific receptors

• Injection of viral genetic material

• Host machinery replicates viral components

• Assembly of new viruses

• Release from host cell, often destroying it

Why can't viruses reproduce independently?

They lack the cellular machinery (e.g., ribosomes, enzymes) needed for replication and rely entirely on host cells

What types of genomes can viruses have?

• DNA or RNA

• Single-stranded or double-stranded

• Linear or circular

How do viruses differ from prokaryotic and eukaryotic cells?

• No nucleus or organelles

• Cannot metabolize or reproduce independently

• Much smaller (nanometer scale)

What makes viruses effective pathogens?

• High mutation rates

• Ability to evade immune detection

• Efficient replication inside host cells

7 characteirtics of livinf/ of life

MRS GREN (movement, respiration, Sensitivity, growth, reproduction, excreition, nutrition)

MRS GREN

Characteristic	Description
Movement	Ability to move or change position (internally or externally)
Respiration	Chemical reactions that release energy from food (aerobic or anaerobic)
Sensitivity	Ability to detect and respond to stimuli in the environment
Growth	Increase in size or number of cells
Reproduction	Ability to produce offspring (sexual or asexual)
Excretion	Removal of waste products from metabolism
Nutrition	Intake and use of nutrients for energy, growth, and repair