Cellular Transport
Cellular Transport Chapter 8
Cellular Transport • Passive Transport – No energy (ATP) used – Particles move from a high concentration to a low concentration – Down/with the concentration gradient – Concentration gradient » Difference in concentration of particles across a space
Passive Transport • Diffusion – Movement of particles across a space – From high to low concentration
• Osmosis – Diffusion of water across a space
Diffusion
Diffusion
Osmosis
Osmosis
Osmosis • Hypertonic – More solutes, less water
• Hypotonic – More water, less solutes
• Isotonic – Equal amount of solutes and water
Osmosis
Passive Transport • Facilitated Diffusion – Uses a transport (carrier) protein – No energy is required – Down the concentration gradient
Facilitated Diffusion
Cellular Transport • Active Transport – Energy (ATP) used – Particles move from a low concentration to a high concentration – Up/against the concentration gradient
Active Transport • Ion Pumps – Uses a transport (carrier) protein – Energy is required – Up the concentration gradient • Ex. Sodium-Potassium Pump
Active Transport
Active Transport • Endocytosis – Cell takes in materials – Cell creates pouch (vacuole) in membrane to engulf particles
• Exocytosis – Cell releases materials – Vacuole in cell binds with membrane to release particles
Endocytosis and Exocytosis
Endocytosis and Exocytosis
Cell Growth and Reproduction
Cell Size Limitations • Three things that limit the size of a cell: – Diffusion • Rate at which nutrients and wastes enter and leave the cell
– DNA • Controls protein production for cell
– Surface area-to-volume ratio • Too much internal space can lead to the build up of wastes or the inability to get enough nutrients into the cell
Cell Reproduction • Before a cell divides chromosomes must be formed – Chromosomes • Super-coiled DNA • Consist of: – Two sister chromatids – Centromere
Chromosome Structure
Chromosomes • Prokaryotes – Single, circular chromosome
• Eukaryotes – Linear chromosomes – Number varies with organism
Chromosomes • Chromosome number does not regulate organisms’ complexity
Prokaryotes • Reproduce by binary fission
Cell Cycle • Sequence of growth and division of a cell • Interphase – Time between divisions – Majority of cell life • G1 phase - growth • S phase – DNA replication (copy DNA) • G2 phase – growth and prepare for division
• Mitosis – Division of the nucleus
• Cytokinesis – Division of the cytoplasm
Cell Cycle
Mitosis • Prophase – – – –
Chromosomes form Nucleus dissolves Centrioles move to poles of cell Spindle fibers appear
• Metaphase – Chromosomes line up at the center of the cell
• Anaphase – Chromatids separate
• Telophase – Chromatids disassemble – Nucleus re-forms – Spindle fibers dissolve
Mitosis
Cell Cycle
Cytokinesis • Animal Cell – Cleavage furrow forms
• Plant Cell – Cell plate forms
Organization
Organization
Organization
Organization
Organization
Organization
Control of the Cell Cycle • Cancer – Results from uncontrolled cell division – Cell cycle check points are ignored • Proteins that regulate cell cycle are absent or ineffective – Cyclins
• Why? – Gene that regulates their production in mutated – Thus cancer is a result of a mutation within a cell
Control of the Cell Cycle
Cancer • Causes – Carcinogens • Mutagen that causes cancer – Mutagens cause a mutation
• Ex. Cigarette smoke, UV rays, X-rays, asbestos, etc.
• Tumors – Benign • Non- cancerous
– Malignant • Cancerous
Cancer
Cancer
Cancer • Metastasis – The spreading of cancer
Cancer
Cancer
Cancer
Cellular Transport • Passive Transport – No energy (ATP) used – Particles move from a high concentration to a low concentration – Down/with the concentration gradient – Concentration gradient » Difference in concentration of particles across a space
Passive Transport • Diffusion – Movement of particles across a space – From high to low concentration
• Osmosis – Diffusion of water across a space
Diffusion
Diffusion
Osmosis
Osmosis
Osmosis • Hypertonic – More solutes, less water
• Hypotonic – More water, less solutes
• Isotonic – Equal amount of solutes and water
Osmosis
Passive Transport • Facilitated Diffusion – Uses a transport (carrier) protein – No energy is required – Down the concentration gradient
Facilitated Diffusion
Cellular Transport • Active Transport – Energy (ATP) used – Particles move from a low concentration to a high concentration – Up/against the concentration gradient
Active Transport • Ion Pumps – Uses a transport (carrier) protein – Energy is required – Up the concentration gradient • Ex. Sodium-Potassium Pump
Active Transport
Active Transport • Endocytosis – Cell takes in materials – Cell creates pouch (vacuole) in membrane to engulf particles
• Exocytosis – Cell releases materials – Vacuole in cell binds with membrane to release particles
Endocytosis and Exocytosis
Endocytosis and Exocytosis
Cell Growth and Reproduction
Cell Size Limitations • Three things that limit the size of a cell: – Diffusion • Rate at which nutrients and wastes enter and leave the cell
– DNA • Controls protein production for cell
– Surface area-to-volume ratio • Too much internal space can lead to the build up of wastes or the inability to get enough nutrients into the cell
Cell Reproduction • Before a cell divides chromosomes must be formed – Chromosomes • Super-coiled DNA • Consist of: – Two sister chromatids – Centromere
Chromosome Structure
Chromosomes • Prokaryotes – Single, circular chromosome
• Eukaryotes – Linear chromosomes – Number varies with organism
Chromosomes • Chromosome number does not regulate organisms’ complexity
Prokaryotes • Reproduce by binary fission
Cell Cycle • Sequence of growth and division of a cell • Interphase – Time between divisions – Majority of cell life • G1 phase - growth • S phase – DNA replication (copy DNA) • G2 phase – growth and prepare for division
• Mitosis – Division of the nucleus
• Cytokinesis – Division of the cytoplasm
Cell Cycle
Mitosis • Prophase – – – –
Chromosomes form Nucleus dissolves Centrioles move to poles of cell Spindle fibers appear
• Metaphase – Chromosomes line up at the center of the cell
• Anaphase – Chromatids separate
• Telophase – Chromatids disassemble – Nucleus re-forms – Spindle fibers dissolve
Mitosis
Cell Cycle
Cytokinesis • Animal Cell – Cleavage furrow forms
• Plant Cell – Cell plate forms
Organization
Organization
Organization
Organization
Organization
Organization
Control of the Cell Cycle • Cancer – Results from uncontrolled cell division – Cell cycle check points are ignored • Proteins that regulate cell cycle are absent or ineffective – Cyclins
• Why? – Gene that regulates their production in mutated – Thus cancer is a result of a mutation within a cell
Control of the Cell Cycle
Cancer • Causes – Carcinogens • Mutagen that causes cancer – Mutagens cause a mutation
• Ex. Cigarette smoke, UV rays, X-rays, asbestos, etc.
• Tumors – Benign • Non- cancerous
– Malignant • Cancerous
Cancer
Cancer
Cancer • Metastasis – The spreading of cancer
Cancer
Cancer
Cancer
