文档介绍：Chapter 1 morphology , structure and function of prokaryotes
原核生物的形态,结构和功能
Prokaryotes and eukaryotes
major differences
section A
Within the microbial world can be found two different categories of cell type/ prokaryote and eukaryote.
DNA free in the cytoplasm
Only one chromosome
DNA associated with histone-like proteins
May contain extrachromosomal elements called Plasmids
Introns not found in mRNA
Cell division by binary fission - asexual replication only
Transfer of ic information occurs by conjugation, transduction and transformation
DNA is contained with a membra-ne bound nucleus. A nucleolus is
also present
>1 chromosome. Two copies of
each chromosome may be present (diploid)
plexed with histone
proteins
Plasmids only found in yeast
Introns found in all genes
Cells divide by mitosis
Exchange of ic information
occurs during sexual reproduction.
Meiosis leads to the production
of haploid cells (gametes) which can fuse
原核生物和真核生物遗传的和细胞组装上的主要差别
DNA在细胞质中游离
只有一个染色体
DNA与类组蛋白连系
含有染色体外的遗传物质,称为质粒
在mRNA中没有发现内含子
细胞分裂以二等分裂方式,只有无性繁殖
遗传信息传递可通过接合、转导、转化发生
DNA在膜包围的核中,只有一个核仁
多于一个染色体,每个染色体是双拷贝(双倍体)
DNA与组蛋白连系
只在酵母中发现质粒
所有基因中都发现内含子
细胞分裂为有丝分裂
遗传信息交换发生在有性繁殖过程,减数分裂导致产生
单倍体细胞(配子),它们能融合
.原核生物.
真核生物
遗传物质的组装和复制
1. Cytoplasmic membrane contains hopanoids lipopoly-
harides, and teichoic acids found
2. Energy metabolism associated with the cytoplasmic
membrane
3. Photosynthesis associated with membrane systems and
vesicles in cytoplasm
4. Flagella consist of one protein ,flagellin
5. Ribosomes - 70S
6. Peptidoglycan cell walls (eubacteria only:different polymers
in archaebacteria)
anization of
prokaryotes
1. Cytoplasmic membrane contains sterols
2. Mitochondria present in most cases
3. Chloroplasts present in algal and plant cells
Internal membranes, endoplasmic reticulum and Golgi
apparatus present associated with protein synthesis and targetting
5. Membrane vesicles such as lysosomes and peroxisomes present
anizaton of eukaryotes
6. Cytoskeleton