What are the three main principles in cell theory
- DNA is passed between cells during cell division
- the cells of all organisms within a similar species are mostly the same, both structurally and chemically
- energy flow occurs within cells
What do all cells posses and their functions
Proteins which perform most of the cells function
Nucleic acids which store transmit and process information
Carbohydrates which provide chemical energy, carbon,support and identity
Plasma membrane serves as a selectively permeable barrier, separates life from non-life
Differences of structure between eukaryotic and prokaryotic cells
Eukaryotic cells are generally larger
Eukaryotic cells consist of a relatively large number of membrane-bound organelles while prokaryotic cells do not possess such structures.
The genetic material in eukaryotic cells is contained within the nucleus, in prokaryotes this is found free in the cytoplasm in a region called the nucleoid
Common prokaryote cell shapes
Round
Rod
Curved rod
Short rod
Spiral
Helical spiral
Be able to label both eukaryotic and prokaryotic cells
Prokaryotic:
Flagellum - long tail
Pilus - short (look hair like) protein structure on the outside
Capsule - first outer layer
Cell wall - second outer layer
Plasma membrane - third outer layer
Cytoplasm - the solution inside the cell
Ribosome - small little dot like structures
Nucleoid - large squiggly mass where genetic information is stored
Plasmid - small circular/oblong molecules inside the cell
Eukaryotic (Animal):
Cell membrane - outer layer
Cytoplasm - solution inside the cell
Nucleus - brain of the cell
Mitochondria - small pill shaped structure, generates ATP
Eukaryotic (Plant):
Cellulose cell wall - first outer layer
Cell membrane - second outer layer
Cytoplasm - solution inside the cell
Permanent vacuole - large structure inside the cell, helps maintain regular cell processed
Chloroplast - small bean like structure (often shown as green), where photosynthesis occurs
Nucleus - brain of the cell
Mitochondria - small pill shaped structure, generates ATP
Compare and contrast plant and animal cells
Plant and animal cells share the same characteristics however, plant cells also include a cellulose cell wall, chloroplasts and a permanent vacuole.
Cell Wall
Plant only
stiff, surrounds the cell
gives shape and support, helps plant stand upright, made of cellulose
Cell membrane
Both
thin, flexible, like skin, semi permeable
controls what goes in and out of the cell such as water nutrients and waste
Nucleus
Both
large, round, near center of the cell and appears darker
the brains of the cell, directs activities of the cell, contains chromosomes
Nuclear Membrane
Both
thin layer, surrounds the nucleus
protections, controls the materials that move in and out of the nucleus
Mitochondria
Both
oval, footprint shape
powerhouse, burns sugar to produce most energy for the cell
Endoplasmic Reticulum (E. R.)
Both
ribbon like, folded membrane, tubes, can be smooth or rough
delivery system, passageways that carry materials from one part of the cell to another
Ribosome
Both
tiny, dark, round, no membrane, can be attached to the E.R.
makes proteins and passes them to the E.R.
Golgi Body
Both
stacks of flattened sacs, channels, folded membranes
receives proteins and other materials from the E.R., packages them and distributes them to other parts of the cell
Chloroplast
Plant only
oval shaped
captures energy from the Sun and uses it to produce food for plant cells
Large central vacuole
Plant only
large, round, fluid-filled sac
stores water and nutrients needed by cell and also stores waste
Lysosome
Both
small, round, bag like
contains enzymes (chemicals) to digest wastes, food and worn damaged cells
Chromosome
Both
string like coloured bodies
carries the code material (DNA) that controls the cell’s activities
Cytoplasm
Both
fluid, clear, jellylike
constantly moving fluid that contains organelles, provides shape and support
