chapter 27 outline

chapter 27 outline - Jacob Zipperstein Prokaryotes and the...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Prokaryotes and the Origins of Metabolic Diversity Chapter 27 – page 526 I. The world of Prokaryotes a. Prokaryotes i. Found wherever there is life ii. Dated back to 3.5 billion years ago iii. Often live in close association with other prokaryotes iv. Diverse in structure and metabolism. b. Structure and Function i. Most are Unicellular ii. Diversity of cell shapes – main 3 are: 1. sphere 2. rods 3. helices iii. Most have diameters of 1-5 um. iv. Most have cell wall external to the plasma membrane 1. Wall maintains the shape and affords physical protection. 2. Peptidoglycan – consists of polymers of modified sugars. Protects entire cell 3. Gram stain – used to separate species into two groups a. Gram-positive – simpler walls; large amount of peptidoglycan b. Gram-negative – less peptidoglycan; more complex. 4. Capsule – protective layer outside the cell wall. 5. Pili – surface appendages that adhere to other prokaryotes v. Motored by flagella vi. Taxis – movement toward or away from a stimulus vii. Plasmids – small rings of DNA which consists of only a few genes. c. Reproduction i. Asexually – binary fission ii. Transformation – takes up genes from the surrounding environment iii. Conjugation – direct transfer between prokaryotes iv. Transduction – viruses transfer genes between prokaryotes d. Mobile i. Motile bacteria propel themselves by using flagella. II.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/23/2010 for the course ENGLISH 1011 taught by Professor Thompson during the Spring '07 term at Berkeley.

Page1 / 3

chapter 27 outline - Jacob Zipperstein Prokaryotes and the...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online