Chapter 4 Flashcards
What is Cell Theory?
All living organisms are made up of one or more cells, the cell is the smallest unit of life, new cells come from the division of other cells.
What distinguishes Prokaryotic cells from Eukaryotic cells?
Prokaryotic cells have a capsule, while Eukaryotic cells have membrane-bound organelles, a nucleus, and internal organization.
List the types of Prokaryotic cells.
- Bacteria
- Archae
List the types of Eukaryotic cells.
- Protistans
- Fungi
- Plants
- Animals
What is the function of the plasma membrane?
Separates the cell contents from the external environment and regulates movement of substances into and out of the cell.
What is cytoplasm?
A jelly-like mixture of water, sugars, ions, and proteins.
What do ribosomes do?
Assemble polypeptides (i.e., proteins).
What is DNA’s role in cells?
Stores genetic information.
What are the components of a Prokaryotic cell’s outer wall?
- Plasma membrane (inner)
- Cell wall
- Capsule (outer)
What is the structure and function of the capsule in Prokaryotic cells?
A gel-like layer that provides protection and aids in attachment, made of polysaccharides.
Where is Prokaryotic DNA located?
Circular and free-floating in the cytoplasm.
What are plasmids?
Small rings of DNA that can move genes between different individual prokaryotes.
What is the function of pili in Prokaryotic cells?
Hair-like projections that help some prokaryotes attach and interact with their surroundings.
What is the function of flagella in Prokaryotic cells?
Tail-like structures that allow some prokaryotes to move.
Where can Bacteria and Archaea be found?
- Soils
- Surfaces (skin, phones, etc.)
- Intestines
- Extreme environments (hot springs, hydrothermal vents)
What roles do Prokaryotes perform?
- Pathogens
- Decomposers
- Nutrient cycling
- Digestion
What is the domain Eukarya comprised of?
Plants, animals, fungi, and protists.
What is a unicellular eukaryote example?
Yeast.
How many cells are in the human body?
About 37.2 trillion cells.
What are organelles?
Compartment in the cell cytoplasm that has its own plasma membrane and specialized functions.
What is the function of the nucleus?
Holds and protects DNA, coordinates cell function, and instructs the production of proteins.
What is chromatin?
DNA and associated proteins (histones).
What is the rough endoplasmic reticulum (rough ER) responsible for?
Making proteins; it is studded with ribosomes.
What is the smooth endoplasmic reticulum (smooth ER) responsible for?
Making lipids and detoxifying poisons.
What does the Golgi body do?
Finishes lipids and proteins, modifies and packages molecules, synthesizes carbohydrates.
What are vesicles?
Transport materials within the cell, digest waste, and store materials for transportation or later use.
What are lysosomes?
Break down and digest unwanted molecules, cell parts, and waste within a cell.
What is the cytoskeleton responsible for?
Cell movement and structural support.
What are the three major protein filaments of the cytoskeleton?
- Actin filaments
- Intermediate filaments
- Microtubules
What is the role of mitochondria?
Converts energy stored in chemical bonds in sugars to ATP.
What is unique about mitochondrial DNA?
It is inherited only from the mother.
What is the function of chloroplasts?
Converts energy in sunlight into energy stored in chemical bonds (Photosynthesis).
What is the composition of a cell wall in plant cells?
Made of cellulose, a carbohydrate macromolecule.
What do large vacuoles do in plant cells?
Hold water and nutrients, providing support to the plant.
What is the evolutionary significance of the first cells on Earth?
They were ancient prokaryotes, similar in size to modern prokaryotic cells.
What is invagination in the context of cell evolution?
The folding of the cell plasma membrane to create inner compartments.
What is endosymbiosis?
One organism living inside another, benefiting both.
