Cell biology
Protein structure
Complex carbohydrates
Complex carbohydrates
Complex carbohydrates
Announcements * There will be a quiz next laboratory session and like always; it will cover materials from previous lab. and from up-coming one. * Next week lab. is Energy conversion (fermentation). * Home work for this lab. will is posted on my web page. *Another assignment; a prospectus, also due next week and is posted on my web page. * Read through page XIV and XV to be prepared for next week assignment.
Today cells and types of cells Domains of life Prokaryotes and eukaryotes Cell division Diffusion Osmosis
The Cell * It is the the smallest unit of any living organism. * It is basically a protoplasmic mass; that is a cell membrane and cytoplasm. * The cytoplasm is composed of a fluid part (cytosol) and solid structures (organelles) * Some other structures may exist depending on the type of the cell (cell wall in plant cells, cell wall in bacteria). * Based on the type of cell, living organisms are group into three categories.
Domains of life
Cell type * Generally, cells are either prokaryote or eukaryote * Prokaryotes -genetic material (chromosomal DNA) is free in the cytosol. - there is no membrane-bound organelles -no cytoskeleton * Eukaryotes -genetic material (chromosomal DNA) is surrounded by a membrane (the nuclear membrane) -there are membrane-bound organelles (endoplasmic reticulum, Golgi apparatus, mitochondria, chloroplast, etc.) -there is cytoskeleton
Prokaryotes * These are bacteria (eubacteria) * unicellular * They have different shapes, size and environment. * Some are pathogenic and others are beneficial. * Microscopic organisms.
Archaea * These are middle stage between prokaryotes and eukaryotes. * They have ribosomal subunits that is different from bacteria and eukaryotes. * They live in extreme environmental conditions. * They share bacteria in -no membrane-bound organelles -no cytoskeleton -method of cell division - unicellularity * They resemble eukaryotes in - transcription apparatus
Eukaryotes * These includes cells of animals, plants, protozoa, and fungi. * Eukaryotic organisms either uni- or multi-cellular * Humans are multi- cellular eukaryotes. animal cell
Eukaryotes Plant cell
Cell division * Porkaryotes and Archaea - Cell division occur by process termed “simple binary fission” - Basically, the cell double its contents and divide - It a processes of reproduction (multiplication). * Eukaryotes -mitosis… somatic or asexual cell division -meiosis… sexual cell division - in multi-cellular organism e.g human, mitosis is mainly growth related cell division.
Diffusion * It is the process by which particles are transported across the cell membrane. * Particles moves from a region of higher concentration toward a region of lower concentration. * Cell membrane exert a degree of selectivity on the particle that diffuse through it (selective permeability) * O2, Co2, nutrients, etc. diffuse through the cell mem.
Osmosis * It is a process of water molecules movement from hypotonic solution (low solute concentration) to hypertonic solution (high solutes concentration) through a semi-permeable membrane (cell membrane). * Cytoplasm is a hypertonic solution compared to tap water. * What will happen to animal cell thrown into a beaker filled with tap water.. plant cell … Bacterial … * Saline …. 0.9% NaCl, is isotonic solution.
Fun time *15 minutes to read the materials and methods for this laboratory. P 3-4 to 3-9 * Check each station and start work.