BIOL 1030H Lecture Notes - Lecture 1: Osmosis, Fluid Mosaic Model, Homeostasis
26 Jun 2018
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In this course we will consider:
Part 1: How animals deal with the environment variation from cellular to whole animal level
Part 2: Learning about genetics
Holes in cork were considered cells and that they were the building blocks of life
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Microscopes were developed in 1665 by Robert hooke by examining cork
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Skin cells- .1mm
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Neurons- 1m
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Ostrich egg- very large
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All organisms are made of either a single cell or an ensemble of cells
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Introduction to Cells
A plasma membrane that creates a distinct boundary separating the cell interior from the
external environment
1.
The ability to harness materials and energy from the environment
2.
The ability to store and transmit information
3.
Essential features of cells
Separate the inside of the cell from the outside
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Surround many internal structures
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Cells are defined by membranes
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Fish can change the structure of their membranes to adjust to their environment
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Phospholipid- 2 layers, together are amphipathic
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Hydrophilic portion- attracts water, polar (electrons at one end)
a.
When a double bond is present, it causes a kink in the chain
i.
Hydrophobic portion- consists of fatty acids (carbon chains)
b.
Cell membranes are composed of two lipid layers:
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Seen in the digestive system
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if the lipids have just one tail and a large head, they will take on the micelle shape
(spherical).
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If the lipid has a large head and two tails, it will form the phospholipid bilayer
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When you throw the membranes into water
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Van der Waal Forces cause the tails to stick together
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Lipids are associated with each other by weak Van der Waal Forcers
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Long chains = rigid chain
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Short chains= fluid chain
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Double bonds present= more fluid
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No double bonds=rigid
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The length of the carbon chain dictates the fluidity of the membrane
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Cell membranes are dynamic:
Lecture 1
January 10, 2018
5:04 PM
Biology 1030 Page 1
Document Summary
Part 1: how animals deal with the environment variation from cellular to whole animal level. Microscopes were developed in 1665 by robert hooke by examining cork. Holes in cork were considered cells and that they were the building blocks of life. All organisms are made of either a single cell or an ensemble of cells. A plasma membrane that creates a distinct boundary separating the cell interior from the external environment. The ability to harness materials and energy from the environment. Separate the inside of the cell from the outside. Cell membranes are composed of two lipid layers: Fish can change the structure of their membranes to adjust to their environment. Phospholipid- 2 layers, together are amphipathic a. b. Hydrophilic portion- attracts water, polar (electrons at one end) Hydrophobic portion- consists of fatty acids (carbon chains) i. When a double bond is present, it causes a kink in the chain.
