BIOL 2130 Lecture Notes - Lecture 7: Semipermeable Membrane, Glycocalyx, Fluid Mosaic Model

26 views3 pages
27 Mar 2017
Chapter 3
Cells and Tissues
Cells are the structural units of all living things
The human body has 50 to 100 trillion cells
Chemical Components of cells
Most cells are composed of four elements
1. Carbon
2. Hydrogen
3. Oxygen
4. Nitrogen
Cells are about 60% water
Four Concepts of the Cell Theory
1. A cell is the basically structural and functional unit of living organisms
2. The activity of an organism depends on the collective activities of its cells
3. According to the principle of complementarity, the biochemical activities of cells are
dictated by the relative number of their specific subcellular structures.
4. Continuity of life has a cellular basis.
Anatomy of a Generalized Cell
In general, a cell has three main regions or parts:
1. Nucleus
2. Cytoplasm
3. Plasma Membrane
The Nucleus
Control center of the cell
o Contains genetic material known as deoxyribonucleic acid, or DNA
DNA is needed for building proteins
DNA is necessary for cell reproduction
Three regions:
o Nuclear envelope (membrane)
Consists of a double membrane that bounds the nucleus
Contains nuclear pores that allow for exchange of material with rest of
the cell
Encloses the jellylike fluid called the nucleoplasm
o Nucleus contains one or more nucleoli
o Sites of ribosome assembly
o Ribosomes migrate into the cytoplasm through nuclear pores to serve as the site
of protein synthesis
find more resources at
find more resources at
Unlock document

This preview shows page 1 of the document.
Unlock all 3 pages and 3 million more documents.

Already have an account? Log in

Get OneClass Notes+

Unlimited access to class notes and textbook notes.

YearlyBest Value
75% OFF
$8 USD/m
$30 USD/m
You will be charged $96 USD upfront and auto renewed at the end of each cycle. You may cancel anytime under Payment Settings. For more information, see our Terms and Privacy.
Payments are encrypted using 256-bit SSL. Powered by Stripe.