Cell Structure Flashcards
Prokaryotes are subdivided into two. What are these two groups?
Eubacteria and Archaebacteria
Has unique DNA sequence, different membrane lipids, and lacks peptidoglycan,
Archaebacteria
Has cell wall, and considered as larger group.
Eubacteria
BACTERIAL SHAPE: Cocci
Spheres
Bacilli
rod
Spirochetes
Spirals
Diplococci
pairs
Streptococci
chains
Staphylococci
clusters
Eight-membered cocci formation
sarcina
Can be seen on the surface of prokaryotes
Appendages
Used for locomotion
flagella and pili
Known as organ of motility
flagella
3 parts of flagells
basal body, hook, and filament
One flagella visible only on one side
Monotrichous
Multiple flagella at the same side
Lophotrichous
Single flagellum located at both ends
Amphitrichous
Has uniform number of flagella distributed over the body
Peritrichous
Flagellar function
Chemotaxis, Phototaxis
Enables the bacteria to bind/ attach to specific receptor structures and thereby to colonise specific surfaces.
Fimbriae
Virulence factors that allow bacteria to attach to host cells.
adhesins
Short, hair-like structures on the cell surface of prokaryotic cells. They can have a role in movement, but are more often involved in adherence to surfaces, which facilitates infection, and is a key virulence characteristic.
pili
Adherence of symbiotic or pathogenic bacteria to host cells
Ordinary pili
Attachment of donor and recipient cells in bacterial conjugation
Sex pili
Comprises the inner cell membrane and the cell wall of a bacterium
Cell envelope
Considered as an extracellular polymer because it is made up of polysaccharide. It also serves as a physical barrier to prevent the entry of pathogens into the cell.
Glycocalyx
Loosely associated with the bacterium and can be easily washed off
Capsule
Attached tightly to the bacterium and has definite boundaries
Slimy layer
Allows bacteria to adhere to host cells or other environmental surfaces and to maintain shape and envelope rigidity
S-layer
Has high osmotic protection, composed of peptidoglycan, and determines the shape of the cell.
Cell wall
Gram-negative bacteria have walls with ___ layers of peptidoglycan (10% of wall), and high lipid content. These stain pink.
thin
Separates the interior of the cell from the outside environment. Consists of a lipid bilayer that is semi-permeable.
Cell membrane (Cytoplasmic membrane)
Transport nutrients into the cell and also transport toxic substances out of the cell.
Cell membrane
Gel-like fluid inside the cell.
Cytoplasm
Building blocks for cell synthesis or as sources of energy. It has the cell’s water and nutrients.
Cell pool
Sites of protein synthesis
Ribosomes
Reservoir of structural building blocks
inclusions, granules
An irregularly shaped region within the prokaryotic cell that contains all or most of the genetic material.
Nucleoid
The sources of genetic information where it appears to be granular or fibrous
bacterial chromosome
A small circular DNA molecule found in bacteria and some other microscopic organisms. They are physically separate from chromosomal DNA and replicate independently.
Plasmids
Protective trait of plasmids
Drug resistance and profuction of toxins and enzymes
Responsible for holding the components of the cell and protects them from damage. It stores the molecules required for cellular processes and is also responsible for giving the cell its shape.
Cytoplasm
The environment of the organelles and the location of many important biochemical processes
Cytoplasmi matrix
Responsible for the movements and cell structure. Also forms the cytoskeleton.
Microfilaments
Network of tubules and cisternae. It also transport materials, protein, and lipid synthesis.
Endoplasmic reticulum
Packages materials and prepares them for secretion, the exact nature of its role varying with the organism.
Golgi apparatus
Intracellular digestion
Lysosomes
Energy production through metabollic pathways
Mitochondira
Photosythesis
Chloroplast
Contains the double helix genetic material (DNA)
Nucleus
Ribosomal RNA synthesis, ribosome construction
Nucleolus
Strengthen and give shape to the cell
Cell wall and pellicle
