Microorganisms Lecture 1: Cells Overview

A single-celled organism, lacking membrane-bound organelles, including bacteria and archaea.

A complex cell (often multicellular), with membrane-bound organelles, including everything other than bacteria and archaea (like plants, animals, fungi, and protists).

Small living units that interact with environment and other cells, often part of communities.

The membrane that separates the cell's internal environment from the outside.

The jelly-like substance inside a cell, holding organelles & important materials.

The variety of forms and functions of microorganisms, beyond just bacteria.

Ancient bacteria capable of photosynthesis, playing a key role early in Earth's history.

Bacteria performing photosynthesis without oxygen production.

Small size of prokaryotic cells leads to a high surface-to-volume ratio, enabling faster nutrient uptake, waste removal, and overall growth, compared to larger cells.

Bacteria come in various shapes, including spherical (coccus), rod-shaped (bacillus), spiral (spirillum), and comma-shaped (vibrio).

The cytoplasmic membrane acts as a selective barrier, controls what enters and leaves the cell, anchors essential proteins, and plays a role in energy production for the cell.

Small cells have a higher surface area to volume ratio, enabling faster nutrient intake and waste removal compared to larger cells.

Microbiology is categorized into different studies, focusing on specific groups of microorganisms like bacteria, protozoa, fungi, viruses, and photosynthetic eukaryotes.

Microorganisms are significant in various ways, including causing illness, acting as helpers in agriculture and nutrition, contributing to food production, and being useful in industrial processes.

A phospholipid bilayer forms the cell membrane, with a hydrophobic core that repels water. This structure is crucial for protecting the cell and controls what enters and exits the cell.

Bacteria's shape directly affects its ability to function. Different shapes promote different attributes which further affects the role of the bacteria in their environment.

The water-attracting portion of a phospholipid molecule, typically found on the outer layer of the cell membrane.

The chemical bond that connects glycerol to fatty acids in a phospholipid molecule.

The chemical bond that connects glycerol to fatty acids in a phospholipid molecule, specifically in archaeal membranes.

A repeating unit that makes up the tail of archaeal phospholipids.

The bursting of a cell due to the influx of water caused by differences in osmotic pressure.

A rigid polysaccharide found in the cell walls of most bacteria, providing structural strength.

An acidic molecule found in the cell walls of gram-positive bacteria, attached to peptidoglycan.

An acidic molecule found in the cell walls of gram-positive bacteria, attached to the lipids.

A highly resistant, dormant form of a bacterial cell, capable of surviving harsh conditions.

The process by which a vegetative bacterial cell converts into an endospore.

The process by which an endospore reverts back to a vegetative bacterial cell.

Long, thin appendages that rotate, propelling bacteria through liquid environments.

Similar to flagella, but found in archaea, rotating for movement.

The main part of a flagellum, made of multiple flagellin protein molecules.

Connects the filament to the flagellum motor, allowing for rotation.

The complex machinery that powers the rotation of the flagellum.

Certain bacteria that move across surfaces without using flagella, requiring direct contact with a solid surface.

The process of cell replication in eukaryotic organisms, involving mitosis and meiosis.

The central control center of eukaryotic cells, housing the chromosomes and nucleolus.

A structure within the nucleus where ribosomal RNA (rRNA) is synthesized.

Organelles in eukaryotic cells responsible for cellular respiration, providing energy for the cell.

Organelles found in anaerobic eukaryotic microbes, producing energy through fermentation.

The science of classifying organisms, organizing them into groups based on shared characteristics.

A two-part naming system for organisms, using genus and species names, established by Carolus Linnaeus.

Adenine (A) always pairs with Thymine (T), and Guanine (G) always pairs with Cytosine (C).

The amount of Adenine (A) in DNA always equals the amount of Thymine (T) or Uracil (U) in RNA, and the amount of Guanine (G) always equals the amount of Cytosine (C).

When DNA replicates, each new double helix contains one original strand from the parent molecule and one newly synthesized strand.

The primer is a short RNA sequence that provides a starting point for DNA polymerase III to attach and begin DNA synthesis.

The leading strand is synthesized continuously in the 5' to 3' direction, while the lagging strand is synthesized discontinuously in Okazaki fragments.

Topoisomerase prevents supercoiling of the DNA strand by cutting and rejoining the DNA molecule.

DNA polymerase can detect mismatches in base pairing and correct them, ensuring high accuracy in DNA replication.

Transcription involves the process of copying DNA into RNA using RNA polymerase. The process includes initiation, elongation, and termination.