Class Notes (839,559)
Canada (511,394)
Biology (6,826)

Biology Day 2 Lecture Notes.docx

3 Pages

Course Code
Biology 1201A
Richard Gardiner

This preview shows page 1. Sign up to view the full 3 pages of the document.
Biology Day 2 Lecture Notes A Tour of the Cell Early microscope: Anthony van Leeuwenhoek – single lens – ca. 1673 Used microscope to look at fungal cells. The Cell: first person to coin the word ”cell” to describe the tiniest components of living systems – plants (Robert Hooke) In modern telescopes, “dyes” are used to see ultraviolet rays There are many microscopic techniques. Different images include surface image and cross image The Electron Microscope - Resolution limit of light microscope is about 0,2 microns (size of a small bacterium, remember 1 micron is .001 mm) - Magnification limit of about 1000 times - In 1950’s, the introduction of the electron microscope enabled organelles, viruses, proteins, etc… to be imaged Light Microscope - The minimum resolution of a light microscope is about 2 microns, the size of a small bacterium - Light microscopes can magnify effectively to about 1000 times the size of the actual specimen - At higher magnifications, the image blurs Cell Fractionation - Take cells apart to study their components - Centrifuge is used to fractionate cells and separate their major organelles - Ultracentrifuges are capable of speeds as fast as 150,000 rpm applying forces over 1 million times the force of gravity The Cell Cell = simplest collection of matter which has all the properties of life 1. Lowest hierarchical level which is alive. 2. Cell is basic unit of life. 3. Cell performs all functions necessary to live and reproduce. Virus - Occur in virtually every kind of organism - Some wreck havoc, others cause no disease or outward sign of their presence - Often highly specific to host - Can reproduce only when they enter a cell CELLS – TWO BASIC TYPES: Prokaryotic Cells - pro: before and karyote – nucleus – Examples – bacteria, cyanobacteria, mycoplasmas, etc - no nucleus (genetic information in area called nucleoid - Visible components – plasma membrane, ribosomes, nucleoid, cytoplasm, cell wall, pill, flagella, mesosomes, photosynthetic membranes - Bacteria range in size from approximately as small as the largest viruses to large enough for single cells to be visible
More Less
Unlock Document

Only page 1 are available for preview. Some parts have been intentionally blurred.

Unlock Document
You're Reading a Preview

Unlock to view full version

Unlock Document

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.