Topic 1 Flashcards
Nerve cells
Act like fibre optic cables
Connect CNS to the rest of the body
Longest cells in the body
Sex cells
Sperm and eggs
Egg cells - big they are visible without needing a microscope
Red blood cells
Emptied of almost all cell contents to help them carry the maximum amount of oxygen to cells
Monocytes
Hunt down rogue invading cells
Change shape constantly to chase down their quarry
In blood stream
Natural selection
organisms produce more offspring that are able to survive in their environment
Those that are better physically equipped to survive grow to maturity and reproduce
Cell theory
All organisms are made of cells
Cells are the basic units of life
Cells come from pre-existing cells that have multiplied
Eukaryote
has nucleus, cytoskeleton, cytoplasmic organelles
larger
more DNA
Multiple linear DNA molecules
Prokaryote
NO nucleus, cytoskeleton, cytoplasmic organelles
smaller
less DNA
Single circular DNA molecule
Cellular evolution
Formation of Earth > first cells > first eukaryotes, oxidative metabolism > multi cellular organism > present
Tissues
complex organisational arrangements of cells to fulfil specific functions
Epithelial tissue
GI tract, respiratory tract, skin
Muscle tissue
- cardiac
- smooth
- skeletal
Nervous tissue
brain, spinal cord, nerves
Organs
formed by different combinations of these basic tissue types
Apoptosis
Programmed cell death
Normal part of development