ESSENTIALS Flashcards
General characteristics of living system
1) Determined in space & time
2) Genetic & structural unity, hierarchical organization
3) Reproduction
4) Open thermodynamical systems (reduction of entropy); flow of matter, energy & information
5) Metabolism
6) Autoregulation: feedback system
7) Reactivity to external stimuli
8) Ontogeny
9) Phylogeny (evolution)
Why do viruses need a host?
No organelles:
- Can’t make ATP
- Can’t reproduce
Stages of viral replication
Attachment Penetration Synthesis of NA & proteins Maturation Release
People involved with modern cell theory (6)
Hooke Leeuwenhoek de Mirbel Lamarack Schwann, Schleiden Virchow Purkyne
Modern cell theory (6)
1) All know things are made up of cells
2) Cell = structural & functional unit of living things
3) Cells come from pre-existing cells
4) Cells are basically same in chemical composition
5) Cell contain hereditary information
6) All energy flow of life occurs within cells
Cell organelle
Compartments limited by membrane
“Cell” Hierarchy
Molecule Macromolecule Supramolecular complex Cell organelle Cell
Nucleus includes…
Nuclear pores
Nuclear lamina
Nuclear matrix
Nucleoplasm
Types of vesicles (GA)
Exocytotic v. (constitutive secretion)
Secretory v. (regulated secretion)
Lysosomal v.
Function of vacuoles
Maintain turgor pressure Maintain acidic internal pH Enable change shape of cell Remove unwanted substances Isolate harmful materials Push contents against cell membrane; chloroplasts closer to light Role in autophagy
Autophagy
Destruction of invading bacteria
Holism
System as a whole determines how the parts behave
Hypercycle
Organisation of self-replicating molecules connected in a cyclic manner
Capsomeres
Identical protein subunits that form capsid
Types of penetration (virus)
TRANSFER viral particle
TRANSFER viral genome
FUSION viral envelope
Proteases
Perform proteolysis
Gene Expression in Viruses:
ds(+/-)DNA
Bacteriophages
Animal viruses
Gene Expression in Viruses:
ss(+RNA)
Retroviruses
OR
Bacteriophages
Animal/plant viruses
Gene Expression in Viruses:
ss(-)RNA
Bacteriophages
Transformation
A bacterium takes up a piece of DNA floating in its environment
Transduction
DNA is accidentally moved from 1 bacterium to another by a virus
Conjugation
DNA is transferred between bacteria through a pilus
Fertility factors
Chunk of DNA that codes for proteins that make up pilus
Binary fission vs Mitosis PURPOSE
M: Cause organism to grow larger or replace old, worn-out cells with new ones
BF: How bacteria reproduce or add more bacteria to the population