CH. 4 Sapling HW
Select the phrases that describes the plasma membrane.
- creates a barrier between the inside and outside of the cell - maintains the correct ion concentration inside the cell
Select all of the correct statements about extracellular matrix found in animals.
- it contains water and a network of proteins and can be flexible - its functions include holding cells together in tissues
Which tenet of cell theory is described by the following paragraph about the historical observations of cells? Cell theory began to develop in 1839, following the research of Marrhias Schleiden and Theodor Schwann into plant and animal tissues. Both the botanist Schleiden and the physiologist Schwann noticed that every organism they viewed under a microscope, whether plant or animal, was composed of cells. Their observations that all living species are made up of one or more cells led to the early formation of cell theory.
All organisms are composed of one or more cells.
Match these characteristics to the appropriate type of microscope.
Light Microscopes: - uses visable light - can be used with living cells - affordable - requires thin samples Electron Microscopes: - bounces electrons off object - preparation kills living cell - high cost - can observe details on opaque samples
Classify each description as being a characteristic of microtubules, intermediate filaments, or actin filaments.
Microtubules: - are composed of tubulin subunits - stabilize the nucleus - maintain cell shapre by resisting compression Intermediate Filaments: - are not involved in cell mobility Actin Filaments (Microfilaments): - make up the core of cilia and flagella - function in muscle contraction - play a role in ameboid movement
Classify each statement as a description of prokaryotic cells or eukaryotic cells.
Prokaryotic Cells: - has a simple structure - is a generally small cell - DNA is not bound inside a membrane - does not contain organelles in the cytosol Eukaryotic Cells: - has a complex structure - is a generally large cell - DNA is bound inside a membrane - contains organelles in the cytosol
Which of the following eukaryotic cell parts is found in the cytoplasm, enables cell movement, and is composed of interconnected protein fibers?
cytoskeleton
This organelle is part of the endomembrane system of the cell and looks like flattened sacs of membranes. It is often referred to as the "post office" of the cell because it sorts, modifies, and repackages proteins and lipids. It then ships the products in vesicles to other parts of the cell or to the plasma membrane, where they may exit the cell. However, this organelle does not participate in the synthesis of proteins and lipids. Identify this organelle.
golgi apparatus
Which cellular component is a membrane-bound organelle that digests nutrients and cellular waste?
lysosome
Which organelle has a smooth outer membrane, an extensively folder inner membrane, and is the site of ATP production in eukaryotic cells?
mitochondria
The genome of an organism is the complete set of DNA that includes all of the organism's genes. Where is the genomic DNA stored in a prokaryotic cell?
nucleoid
Nearly all eukaryotic cells contain a class of small, round organelles that contain oxidative enzymes. The enzymes break down organic substances via oxidation reactions. What are these organelles called?
peroxisomes
Which cellular structure synthesizes proteins?
ribosome