Science Exam Notes
Unit 1 – Biology
● Cell Theory
- All living organisms are comprised of one or more cells
- Cells are the basic unit of life
- Cells arise from the division of existing cells
- History
- 1665 Robert Hooke
- Examined a thin section of cork and noticed a regular pattern of pores
- First person to use the work cell
- 1674 Anton Van Leeuwenhoek
- “Father of microbiology”
- Discovered animalcules
- 1831 Robert Brown
- Discovered nucleus
- 1838 Matthias Schleiden
- Suggested the importance of the nucleus in cell division
- Studied plant cells
- 1839 Theodor Schwann
- Examined animal and specialized tissues to conclude that they are all
composed of cells
- Proposed with Schleiden that “cells are the basic unit of life”
- 1855 Robert Remak
- Proposed that “cells arise by division of other cells”
- 1864 Louis Pasteur
- Conducted experiments that proved Remak’s hypothesis
● Cell Organelles
- Animal cell parts
Cell Part Description of Function in the cell
Structure
Plasma Cell Membrane Selectively permeable - Forms a
border of the cell. protective
Composed of a double barrier around
, layer of phospholipids the cell
- Allows different
substances to
move through it
Cytoplasm Gel-like material made - Helps to move
up of water and materials (eg.
dissolved minerals nutrients and
where cell organelles organelles)
are suspended. - Contains
necessary
nutrients
- Gives the cell
structure and
protects
organelles
Nucleus Contains genetic - Controls all the
information. activities in a
Surrounded by nuclear cell
envelope. - DNA replication,
transcription,
RNA processing
Nucleolus Darker structure within - Produce and
the nucleus assemble the
cell’s ribosomes
Nuclear Envelope Double membrane with - Protect and
(membrane) nuclear pores which separate the
surrounds the nucleus contents of the
nucleus from
the cytoplasm
Ribosome Produced in the - Protein
nucleolus. Can be synthesis
bound to the ER or
freely floating in the
cytoplasm.
Centrioles A cylindrical structure - Helps with cell
of 9 triplets of tubes. division
Centrioles always exist - Organise
, as a pair. microtubules
Rough Endoplasmic Folded interconnected - Folds and
Reticulum membrane covered in packages
ribosomes (rough) that proteins
extends from the - Transportation
nuclear envelope. of the proteins
Smooth Endoplasmic Folded interconnected - Production of
Reticulum membrane with NO fats and oils
ribosomes (smooth) - Detoxification of
that extends from the drugs and toxins
nuclear envelope.
Golgi Apparatus Folded interconnected - Transport, sort
membranes and and modify
vesicles near ER. proteins and
lipids for use in
other places
inside and
outside the cell
Mitochondria A double-membrane - Converts
structure. The inner chemical energy
membrane has many in sugar into
folds to increase energy the cell
surface area. The can use
innermost cavity is the
matrix.
Vacuole Fluid-filled sacs. - Stores food,
waste, and
water
Vesicle Small celular containers - Transport
materials
Lysosome Contains digestive - Breaking down
enzymes. nutrients
- Breaking down
excess/worn-out
cell parts
- Destroy invading
, viruses and
bacteria
- Plant cell parts
Cell Part Description of Function in the cell
Structure
Everything an animal
cell has except for
lysosome and
centrioles
Cell wall A rigid wall that is - Provides
composed mostly of strength,
cellulose. protection, and
support
- Selecctive
barrier
Chloroplast A double-membrane - Site of
structure. The inner photosynthesis
membrane has many
folds to increase
surface area. The
innermost cavity is
called the stroma. It is
green in colour due to
chlorophyll.
● Cell Cycle
- The cell’s DNA instructs it on when to divide and when to die
- Cells divide due to:
- Growth
- A cell’s nucleus grows much slower than the rest of the cell
- A cell reaches a maximum size due to limitations in
communication when the cell is too big
- Reproduction
- Binary Fission
Unit 1 – Biology
● Cell Theory
- All living organisms are comprised of one or more cells
- Cells are the basic unit of life
- Cells arise from the division of existing cells
- History
- 1665 Robert Hooke
- Examined a thin section of cork and noticed a regular pattern of pores
- First person to use the work cell
- 1674 Anton Van Leeuwenhoek
- “Father of microbiology”
- Discovered animalcules
- 1831 Robert Brown
- Discovered nucleus
- 1838 Matthias Schleiden
- Suggested the importance of the nucleus in cell division
- Studied plant cells
- 1839 Theodor Schwann
- Examined animal and specialized tissues to conclude that they are all
composed of cells
- Proposed with Schleiden that “cells are the basic unit of life”
- 1855 Robert Remak
- Proposed that “cells arise by division of other cells”
- 1864 Louis Pasteur
- Conducted experiments that proved Remak’s hypothesis
● Cell Organelles
- Animal cell parts
Cell Part Description of Function in the cell
Structure
Plasma Cell Membrane Selectively permeable - Forms a
border of the cell. protective
Composed of a double barrier around
, layer of phospholipids the cell
- Allows different
substances to
move through it
Cytoplasm Gel-like material made - Helps to move
up of water and materials (eg.
dissolved minerals nutrients and
where cell organelles organelles)
are suspended. - Contains
necessary
nutrients
- Gives the cell
structure and
protects
organelles
Nucleus Contains genetic - Controls all the
information. activities in a
Surrounded by nuclear cell
envelope. - DNA replication,
transcription,
RNA processing
Nucleolus Darker structure within - Produce and
the nucleus assemble the
cell’s ribosomes
Nuclear Envelope Double membrane with - Protect and
(membrane) nuclear pores which separate the
surrounds the nucleus contents of the
nucleus from
the cytoplasm
Ribosome Produced in the - Protein
nucleolus. Can be synthesis
bound to the ER or
freely floating in the
cytoplasm.
Centrioles A cylindrical structure - Helps with cell
of 9 triplets of tubes. division
Centrioles always exist - Organise
, as a pair. microtubules
Rough Endoplasmic Folded interconnected - Folds and
Reticulum membrane covered in packages
ribosomes (rough) that proteins
extends from the - Transportation
nuclear envelope. of the proteins
Smooth Endoplasmic Folded interconnected - Production of
Reticulum membrane with NO fats and oils
ribosomes (smooth) - Detoxification of
that extends from the drugs and toxins
nuclear envelope.
Golgi Apparatus Folded interconnected - Transport, sort
membranes and and modify
vesicles near ER. proteins and
lipids for use in
other places
inside and
outside the cell
Mitochondria A double-membrane - Converts
structure. The inner chemical energy
membrane has many in sugar into
folds to increase energy the cell
surface area. The can use
innermost cavity is the
matrix.
Vacuole Fluid-filled sacs. - Stores food,
waste, and
water
Vesicle Small celular containers - Transport
materials
Lysosome Contains digestive - Breaking down
enzymes. nutrients
- Breaking down
excess/worn-out
cell parts
- Destroy invading
, viruses and
bacteria
- Plant cell parts
Cell Part Description of Function in the cell
Structure
Everything an animal
cell has except for
lysosome and
centrioles
Cell wall A rigid wall that is - Provides
composed mostly of strength,
cellulose. protection, and
support
- Selecctive
barrier
Chloroplast A double-membrane - Site of
structure. The inner photosynthesis
membrane has many
folds to increase
surface area. The
innermost cavity is
called the stroma. It is
green in colour due to
chlorophyll.
● Cell Cycle
- The cell’s DNA instructs it on when to divide and when to die
- Cells divide due to:
- Growth
- A cell’s nucleus grows much slower than the rest of the cell
- A cell reaches a maximum size due to limitations in
communication when the cell is too big
- Reproduction
- Binary Fission
