prokaryotes and eukaryotes; prehend a special life: viruses
1. About “Cell Biology”
What?
Forwhy?
How to study?
The NIH of USA(1988): “What is popular in research today？”
C. The cell is the foundation of reproduce, and the bridge of inheritance.
D. The cell is the growing and developing basis of life
Human fetal development. (a)At 5 weeks, limb buds, eyes, the heart, the liver and rudiments of all other organs have started to develop in the embryo, which is only about 1cm long. (b)Growth and development of the offspring, now called a fetus, continue during the second trimester. This fetus is 14 weeks old and about 6cm long. (c)The fetus in this photograph is 20 weeks old. Now the fetus grows to about 30cm in length.
An especially dramatic example of animal cloning was reported in 1997. Dolly the first animal ever cloned from a cell derived from an adult.
Dolly and her daughter
A. The cell is the structural unit of life, All organisms is make up of cells.
B.The cell is the functional unit of organisms. All metabolic activity is based on cells.
through the cytoplasm via diffusion.
6. Two fundamentally different classes of cells: Prokaryotes and eukaryotes
A. Prokaryotic and eukaryotic cells are distinguished by the size and the types of internal structures, or organelles, especially if there is nuclear envelope.
2.The cell is basic unit of structure and function for all organisms.
3.All cells arise only from preexisting cells by division.
3. Why are cells the basic units of life?
What we know//How we know.
ISI, USA(1997) : SCI（Science Citation Index）Papers:
Three tops of research fields:
No1: Signal transduction； No2: Cell apoptosis； No3: Genome and post-genomic analysis。
The microscope used by Robert Hooke and the honeycomb-like network of “cell” he drawed in 1665
Cell theory has three basic tenets:
1. All organisms are composed of one or more cells.
2. The Cell Theory: A Brief History
The discovery of cells followed from the invention of the microscope
In 1665, Robert Hooke saw a network of tiny boxlike compartments that reminded him of a honeycomb. He called these little compartments “cellulae”, a Latin term meaning little room. It is from this word we get our present-day term, cell.
Bacteria are prokaryotes, they arose 3.5 billion years ago; Protists, fungi, plants, and animals are eukaryotes. The first eukaryotes arose 1.5 billion years ago.
分子细胞生物学 Molecular CELL BIOLOGY
主讲教师：丁明孝，陈建国，张传茂
Chapter 1
Introduction to the cell
Learning Objectives
1.About Cell Biology 2.Look briefly at the history of cell theory; 3.Consider the basic properties of cells; pare some characteristics of பைடு நூலகம்wo different classes of cells:
The process of cloning Dolly
Is there any practical value to such technology?
4. Basic properties of cells
A. Cells are highly complex and organized, capable of self-regulation;
E. Cell (nucleus) is totipotent, which can create a new organism of the same type
As a general rule, the cells of a multicellular organism all contain the same set of genes. For animals, the first evidence that even highly specialized cell carry a full complement of genes was verified by the experiment of tadpole nuclei transplanting into unfertilized egg that had been deprived of its own nucleus. Some can develop swimming tadpoles. This is animal cloning.
B. Characteristics that distinguish prokaryotic and eukaryotic cells
(1) Complexity: Prokaryotes are relatively simple, eukaryotes are more complex in structure and function
Johns Hopkins univesity,in 1951
D. Cells are able to respond to stimuli via surface receptors that sense changes in the chemical environment.
Cells within plant or animal respond to stimuli less obviously than single-celled protist. But they respond. They posses receptors that interact with substances in the environment in highly specific ways. For example, the receptor on the cell surface can respond to hormones and growth factors.
Cells acquire and utilize energy.
B. All cells share similar structure,
composition and metabolic features:
Plasma membrane, DNA/RNA, and Ribosome.
C. Cells can capable of producing more of themselves, even grow and reproduce in culture for extended periods.
HeLa cells are cultured tumor cells isolated from a cancer patient named Henrietta Lacks in 1951. It is the first human cell to be kept in culture for long periods of time and is still used today.