Biology #4: Cell Structure and Function
What type of cell has free floating DNA?
Prokaryotic cell
cell wall
- Only in plants -rigid-structure; surrounds the cell membrane -provide rigid structure and support -Due to its makeup, a mixture of cellulose, polysaccharides, and imbedded proteins, the cell wall is able to help maintain the shape of the cell and prevent excess intake or loss of water. -Only in the plant cell, thick line protecting the inside of the cell
Lysosomes
-In animal cells -circular structures throughout cytoplasm -digests -The lysosome uses enzymes to break down large molecules. -Lysosomes and the enzymes they contain are both made in the rough endoplasmic reticulum and then transferred to the Golgi apparatus for further processing. -A lysosome provides an acidic environment where enzymes can digest large macromolecules without disturbing the functions of other molecules important to the cell. Small structures shaped like a circle floating around the cell
Golgi apparatus
-In both types of cell -flattened stack of membranes; usually close to ER -process and package proteins for export -It is also known as the "post office" of the cell. It works with the endoplasmic reticulum to transport the proteins. -Vesicles that bud off of the endoplasmic reticulum attach to the Golgi apparatus's membrane. - membrane and contents of the transport vesicle become incorporated into the Golgi apparatus, where the protein contents are then modified and stored. At other end of the Golgi apparatus, new vesicles will form and be pinched off to carry materials to other sites in the cell as needed. -Structure floating inside the cell that has loops stacked on top on loops
Cytoplasm
-In both types of cell -jelly-like between the nucleus and cell membrane. -cushions and holds organelles -It is a mixture of water and dissolved salts, ions, and organic molecules. -Many of these substances involved in reactions that occur within the cytoplasm, while others are transported to various organelles to be used.
Rough ER (endoplasmic reticulum)
-In both types of cell -tubes that are studded with ribosomes makes, modifies and transports proteins -Rough ER has ribosomes all over it. -the rough ER makes its own proteins and phospholipids to add to its membrane. -portions of the ER's membrane are pinched off to form sealed sacs called transport vesicles. -vesicles newly made proteins from the rough ER to the cell's Golgi apparatus. -Loop-like structure that surrounds the nucleus and has dots all over it
Compare and Contrast Plant and Animal Cells:
A: Small Vacuoles B: Cell membrane, Ribosomes, Nucleus, Endoplasmic Reticulum, Golgi Apparatus, Mitochondria, Lysosomes P: Large Vacuoles, Cell Wall, Chloroplasts
All of the following are parts of the cell theory EXCEPT?
Cells form from spontaneous generation
Mary decided that she wanted to experiment with the color of her white roses. She placed four roses in four different vases. Mary decided to put a different color dye in each vase. The next day she checked each vase and noticed that the white petals turned into the color of the dye placed in the vase. What two properties of water work together to get the colored dye up to the flower petals?
Cohesion and adhesion
A compound light microscope is used to view an onion root cell specimen. The ocular lens has a magnification power of 10x and the objective lens has a magnification power of 40x. How is the total magnification power of the specimen determined?
Multiplying the power of the objective lens and the power of the ocular lens
What are the2 major parts that Eukaryotes are divided into?
Part #1: Cytoplasm Part #2: Nucleus
Centrosome
Pipe-like structures that look like tubes
This organelle is responsible for sorting, modifying, and packaging the proteins.
Golgi Apparatus
Eukaryote: Part #2 Nucleus
*holds the DNA *Controls what happens in the cell *1 cell may have more than 1 nucleus
Eukaryote: Part #1 Cytoplasm
*jelly-like substance found between the nucleus and the cell membrane. * also found in prokaryotes *Supports and cushions organelles *organelles- small membrane-bound organs that perform "jobs" within the cell.
Nuclelous
-In both types of cell -Mass inside the nucleus -makes ribosomes - Some cells only have one nucleolus inside the nucleus, while others have two or more; depends on the species as well as the stage in the cell's reproductive cycle. -Small circle inside the nucleus
Nucleus
-In both types of cell -dark mass in the center of cell -control center -Nucleus controls the activity in the cell. Most of the cell's DNA is found in the nucleus -it contains a tangled mass of chromatin that appears darker than its surroundings. -Inside the nucleus, the cell's DNA and some proteins are packed together into chromosomes. When the cell is not in the process of dividing, the chromosomes are stringy and entangled, which makes it too difficult to identify them as individual structures.
Mitochondria
-In both types of cell -kidney-shaped w/membranes inside -breaks down glucose for energy (cellular respiration) -is enclosed in a layer of two membranes. The inner layer has folds in the membrane, called cristae, while the outer layer is smooth. -structure suits its functions well because the folds in the inner membrane provide additional surface area on which important reactions occur, allowing each mitochondrion to do more work. -Some have one single mitochondrion, but often, cells have hundreds or even thousands of mitochondria. -number of mitochondria in a cell relate to its metabolic activity, or the amount of energy it needs. -Structure that looks like a kidney bean with a loop-like structure inside
Smooth ER (endoplasmic reticulum)
-In both types of cell -membranous tubes -modifies and transports proteins & lipids -participates in various metabolic processes, including the construction of lipids, the deconstruction of carbohydrates, and the detoxification of substances that may otherwise be harmful to the cell. -Little loop-like structures surrounding the nucleus that are smooth in appearance
Ribosome
-In both types of cell -small dots- free in the cytoplasm or attached to Rough ER -make proteins -They are also known as the "factory" of the cell. Ribosomes look like little dots on rough ER. -made in the nucleolus, and can be found in two main locations within a cell. 1)Free ribosomes are found separated within the cell's cytoplasm 2)while bound ribosomes are found attached to another organelle called the rough endoplasmic reticulum. -made up of RNA and protein molecules. -ribosomes consist of two separate parts. Long protein chains are assembled between the two parts of the ribosome.
Nuclear pore
-In both types of cell -small holes in nuclear envelope -allows for substances to go in and out of nucleus
nuclear envelope
-In both types of cell -surrounding membrane of nucleus -Surrounds/separates the nuclear contents
cell membrane
-In both types of cell -thin layer around the cell contents -encloses cell contents -The cell membrane is also called the plasma membrane. It is the protective outer layer of the cell. -Each organelle inside a eukaryotic cell is also surrounded by a membrane. -serve as a selective barrier for the organelles and determine what can enter or leave. -is made up of lipids and contains a variety of proteins. -The outer thick layer covering the cell
Cytoskeleton
-In both types of cell -thread-like fibers throughout cytoplasm -movement, structure/support -functions of the cytoskeleton are comparable to the bones and muscles of our bodies -the fibers of the cytoskeleton give the cell shape, anchor many of the organelles in place, and direct the movement of organelles. -the backbone of the cell
Vacuole
-In both types of cell A: Small- several P: 1 big -pockets in cells -stores water and waste -Vacuoles and vesicles are both membrane-enclosed sacs, but vacuoles are usually larger. -Blue water-like storage area. Small in the animal cell and large in the plant cell. Takes up most of the plant cell
Leukoplasts
-Only in plant cells -grainy circular structures -store starch
Chloroplast
-Only in plant cells -green oblong w/ membranes inside; throughout cytoplasm -convert light, inorganics (CO2, H2O) to glucose for energy (photosynthesis) -green in color because they contain the green pigment chlorophyll. -Chloroplasts are enclosed by a double membrane and contain a system of membranes arranged in stacks of flattened sacs. -provides a lot of surface area on which reactions can occur. -Green oval-shaped structure located only in plant cells. Has small circles in the inside of the structure
Cell Plate
-Only in plants -lines that separate the cell in half -cell division.
3 Parts of the Nucleus
1) nuclear envelope - surrounds the nucleus 2) nuclear pore - holes in nuclear envelope 3) nucleolus- mass of proteins & RNA; where ribosomes are made.
Which type of solution makes the concentration of the solute higher inside the cell membrane and lower outside?
A hypotonic solution
Where are eukaryote cells found?
Eukaryotic cells can be found in animals, plants, fungi, and protists.
Plant and animal cells are similar in many ways, but there are some ways they are different. What are ways that plant and animal cells are different?
Plant cells have chloroplast
This type of microscope is used to study the detail in samples. It produces a three-dimensional image of the specimen.
Scanning electron microscope
What is the main function of the cell membrane?
The cell membrane allows material to enter and leave the cell
Water has the ability to dissolve many substances. This is due to which property of water?
Universal solvent
Centrioles
_Only in animal cells -stick-like structures close to cell membrane -used for cell reproduction