02.04 Cell Structure and Function
Vacuoles
-Cell organelle that stores materials such as water, salts, proteins, and carbohydrates -Vacuoles and vesicles are membrane enclosed sacs but vacuole are larger -Vacuoles serve as storage
Nucleus
-Control center of the cell -A part of the cell containing DNA and RNA and responsible for growth and reproduction - # of nucleolus in the nucleus depends on the stage in the cell's reproductive cycle and species
What are two examples of Eukaryotic cells?
plant and animal cells
Organelles are
specialized structures found within a cell
Cytoplasms and cytoskeleton
- materials are transported -network of fibers is called the cytoskeleton -cytoskeleton give the cell shape, anchor many of the organelles in place, and direct the movement of organelles.
Endoplasmic Reticulum
-A cell structure that forms a maze of passageways in which proteins and other materials are carried from one part of the cell to another. -It has two different sections of ER
cell wall
-A rigid layer of nonliving material that surrounds the cells of plants and some other organisms. -Not found in animal cells -surrounds cell membrane -Maintains cells shape and prevents excess intake or loss of water
Golgi apparatus
-A system of membranes that modifies , stores and packages proteins for export by the cell -Proteins are sent outside or inside the cell
Lysosomes
-An organelle containing digestive enzymes -Enzymes break down large molecules into smaller molecules to be used by the cell -Lysosomes and enzymes are made in the Rough(ER) and are transferred to the golgi apparatus -Lysosomes provide a acidic environment
Chloroplast
-An organelle found in plant and algae cells where photosynthesis occurs -Not in animal cells -Contain green pigment chlorophyll -Converts energy from the sunlight into chemical energy
Smooth (ER)
-That portion of the endoplasmic reticulum that is free of ribosomes. -makes lipids, breaks carbohydrates, detoxify substances that are harmful to the cell
Mitochondria
-enclosed in a layer of 2 membranes -inner layer has folds in the membrane, called cristae, while the outer layer is smooth -inner layer provides additional surface area allowing important reactions occur -Mitochondria is also called the powerhouse of the cell -Mitochondria takes in nutrients and break them down -Cellular Respiration occurs - # of mitochondria relates to its metabolic activity, or the amount of energy it needs
Ribosomes
-location for protein synthesis -cell's smallest organelles -free ribosomes are found spearate in cell's
Rough (ER)
-surface is studded with ribosomes -Ribosomes synthesize proteins and the membrane keeps the proteins separate from the rest of the cell -Makes proteins and phospholipids to add to the membrane -forms transport vesicles -Vesicles carry the proteins to the golgi apparatus
Cell membrane (plasma membrane)
-the semipermeable membrane surrounding the cytoplasm of a cell -determines what leave and enter a cell -made of lipids and variety of proteins
isotonic solution
A solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution
hypertonic solution
A solution in which the concentration of solutes is greater than that of the cell that resides in the solution
hypotonic solution
A solution in which the concentration of solutes is less than that of the cell that resides in the solution
Where can eukaryotic cells be found?
Animals, plants, fungi and protists
What does the chloroplast do?
Makes food during photosynthesis
What do all eukaryotic cells contain?
Mitochondria
What's at the center of a nucleus?
Nucleolus ( Nuclear pores allow material to enter and leave the nucleus ) - makes ribosomes
What do plant and animals cells have?
Organelles, cell membrane ( protective outer layer ), nucleus ( controls the cells activity ), Mitochondria ( provides cell with energy ), Endoplasmic reticulum ( transports materials to and from the nucleus ), Ribosomes ( Proteins are made ), Golgi Apparatus ( DIstributes proteins ), Lysosome ( Breaks down food ), Vacuole ( stores water and food and maintains shape of a plant )
Difference between plant and animal vacuoles
Plants have a large vacuole Animals have smaller vacuoles
What's the additional layer in the plant cell?
cell wall ( it works to maintain the shape of the plant cell )
Cellular Respiration
Process that releases energy by breaking down glucose and other food molecules in the presence of oxygen
What's the difference between Rough(ER) and smooth (ER)?
Rough (ER) has ribosomes all over it Smooth (ER) has a smooth texture
What is only found in plant cells?
chloroplasts and cell walls