Cell Biology PDF
Document Details
Uploaded by IrreplaceablePeninsula
ISF College of Pharmacy, Moga
Tags
Summary
This document provides an overview of eukaryotic cell structure and function. It details the roles of internal membranes, and explains the similarities and differences between plant and animal cells. It also describes the function of the nucleus in protein production.
Full Transcript
• An eukaryotic cell has internal membranes, which partition the cell into compartments. • These membranes also participate in metabolism as many enzymes are built into membranes. ee • The general structure of a biological membrane is a double layer of phospholipids and diverse proteins. • Each...
• An eukaryotic cell has internal membranes, which partition the cell into compartments. • These membranes also participate in metabolism as many enzymes are built into membranes. ee • The general structure of a biological membrane is a double layer of phospholipids and diverse proteins. • Each type of membrane has a unique combination of lipids and proteins for its specific functions. – Ts For example, those in the membranes of mitochondria function in cellular respiration. Plant & Animal Cells • Similarities – Both are eukaryotic cells – Both contain similar organelles – Both are surrounded by cell membrane Plant & Animal Cells • Differences – Plants have • Cell wall – provides strength & rigidity and is not found in animal cells. • Have chloroplasts that is photosynthetic and are not found in animal cells. – Animals have • Organelle lysosomes, centriols and flagella are not found in plants. • Centrioles have important role in cell division. 1. The nucleus: Contains the cell’s genetic library • The nucleus contains most of the genes in an eukaryotic cell as it is the repository for genetic material. • The nucleus is separated from the cytoplasm by a double membrane called nuclear envelope. • It directs activities of the cell. • The nuclear membrane contains pores that allow large macromolecules and particles to pass through. • The nuclear membrane is maintaining the shape of the nucleus. mm • The nucleus contains “chromatin fiber” which is made up of DNA and proteins. • When the cell prepares to divide, the chromatin fibers coil up and condensed to be seen as “chromosomes”. • Each eukaryotic species has a characteristic number of chromosomes. - A typical human cell has 46 chromosomes, but sex cells or gametes (eggs and sperm) have only 23 chromosomes. I • The nucleus directs protein synthesis by synthesizing messenger RNA (mRNA). – The mRNA travels to the cytoplasm and combines with ribosomes to translate its genetic message into the primary structure of a specific protein. • Nucleolus is a dark region involved in production of ribosomes.
