Cell Theory
All organisms are composed of cells
All cells come from pre-existing cells
The cell is the basic unit of life
what is the cell/plasma membrane
Phospholipid Bilayer
double layer Phospholipid molecules with hydropholic tails pointing inward and the hydrophilic heads facing outwards
Protein Molecules
1.Transport ions and molecules across the plasma membrane 2.Enzymes to carry out chemical reactions 3.Receptors for hormones
Cholesterol Molecules
found between phospholipids tails to prevent them from sticking together.
Carbohydrate Chain
1.Adhesion to other cells Recognition of molecules at the membrane surface
Passive Transport
Movement of materials through the plasma membrane Does not require energy Ex: oxygen, carbon dioxide molecules, water, lipids
Diffusion
Form of passive transport Movement of ions or soluble molecules that move from a region of higher concentration to a region of lower concentration High Concentration- a lot of molecules in a smaller area Low Concentration- molecules are very spread out Diffusion results from the random movement of molecules
Osmosis
The diffusion of water through the plasma membrane, or any semipermeable membrane Ex: vacuoles Water moves from an area of low solute concentration to an area of high solute concentration Solute- the substance that gets dissolved Ex: sugar water- sugar is the solute
Facilitated Diffusion
A type of passive transport No energy required Passage of molecules and ions bound to specific carrier proteins, across the membrane, down their concentration gradients Carrier Protein: a. Protein responsible for transporting specific substances through the cell membrane b. Fixed and part of the membrane Move down the concentration gradient- high to low Sugar and Amino Acids move this way a. Too big to move directly through the membrane Active Transport
Active Transport
Movement of materials AGAINST a concentration gradient a.Low solute concentration to high solute concentration -ENERGY REQUIRED!!!
Endocytosis
Materials are ingested by the cell The membrane forms a vesicle around the material ingested
Exocytosis
How bulky particles or large molecules are transported out of a cell Vesicle binds with the plasma membrane and the particle is pushed out
Fluid Mosaic Model
what makes up the plasma membrane, A model of cell membrane structure representing the dynamic nature of membrane lipids and proteins
Prokaryotes
Cell membranes and cell wall No real Nucleus- just a large circular molecules of DNA Smaller cells
Eukaryotes
Cell membrane and some have cell wall True Nucleus- DNA found within a nuclear envelope Larger cells
Cell Wall
Only found in plant cells Made up of the polysaccharide cellulose
Nucleus
Carrier of heredity information Surrounded by the nuclear envelope/ contain nuclear pores Monitors the cell- ensures that the complex molecules that the cell requires are synthesized
Nucleolus
Found inside the nucleus ribosomes are constructed here
Cytoplasm
the substance that fills the cell, a jellylike fluid inside the cell in which the organelles are suspended
Cytosol
Solution of ions, small molecules and proteins, the semifluid portion of the cytoplasm
Homeostasis
Balanced and stable internal environment, process by which organisms maintain a relatively stable internal environment
Regulation
Control and coordination of various activities ex: Nucleus
Cytoskeleton
Anchors the organelles, network of protein filaments within some cells that helps the cell maintain its shape and is involved in many forms of cell movement
Organelles
Membrane bound compartments
Ribosomes
Small organelles for protein synthesis The can be attached to the Endoplasmic Reticulum or free floating
Golgi body
Looks like stacks of flattened sacs It's the packing and distribution center Packages, modifies, and transports proteins to be sent out to other parts of the cell
Vesicles
The Golgi body produces this organelle A little sac that carries products to the plasma membrane
Vacuoles
Filled with water and solutes It's a supporting element Much larger in plant cells Contains waste products
Mitochondria
Powerhouse of the cell Site of cellular respiration
Converting energy from organic molecules into useful energy for cell Has an oblong shape
Nutrition
Nutrients the cell needs for other functions
Excretion
Removal of cellular waste products
Growth
Utilizes the products of synthesis and requires energy
Smooth Endoplasmic Reticulum
WITHOUT ribosomes Used for lipid synthesis, detoxification, and makes hormones
Rough Endoplasmic Reticulum
WITH ribosomes Used for protein synthesis, and transport of proteins & other materials throughout the cell
Lysosomes
The organelle that contains digestive enzymes to break down or digest organic compounds and old worn out organelles
Centrioles
Only in animal cells Most active during cell division Produce special fibers to pull chromosomes to opposite ends of cell
Cilia/Flagellum
Found on the outside of cells Locomotive purposes in single celled organisms (movement)
Chloroplast
Only found in plant cells Site of photosynthesis
Transport
Absorption and distribution of materials with an organism
Synthesis
Large molecules built from smaller ones (ex: building proteins)
when water moves into a cell because the solute is greater inside the cell
hypotonic
when water moves randomly in/out of the cell
isotonic
when water moves from the inside of the cell outside due to a higher solute concentration outside the cell.
hypertonic