A2.2 - Cell Structure Flashcards
What does cell theory state?
- All living things are composed of cells
- The cell is the basic unit of life
- All cells arise from preexisting cells
What are the common traits of all cells?
- Plasma membrane
- Cytosol
- DNA
- Ribosomes
What role does DNA play in cells?
Stores and transfers information, controls enzyme production, and contains genes for protein synthesis
What is cytoplasm?
The region within a cell consisting of cytosol and where metabolic reactions occur
What is the function of the plasma membrane?
Encloses the cell, protects its contents, and controls interactions with the environment
Define prokaryotic cells.
Cells that lack membrane-bound organelles and have a simpler structure
What is the composition of the prokaryotic cell wall?
Most prokaryotes have a rigid cell wall made of peptidoglycan
Where is prokaryotic DNA located?
In the nucleoid and plasmids
What is binary fission?
Asexual reproduction in prokaryotes involving DNA replication and cell division
What is a key feature of eukaryotic cells?
Compartmentalized structure with specialized organelles
What is the function of the endoplasmic reticulum?
Transportation of materials and synthesis of proteins and lipids
What are the two types of endoplasmic reticulum?
- Rough ER (with ribosomes)
- Smooth ER (without ribosomes)
What is the role of mitochondria?
Site of cellular respiration to produce ATP
What are lysosomes?
Membrane-bound vesicles containing digestive enzymes for breaking down waste
What structures are found in plant cells but not in animal cells?
Chloroplasts and cell walls
What is the purpose of vacuoles in cells?
Storage of substances including nutrients, waste, and water
What are the processes of life that unicellular organisms must perform?
- Homeostasis
- Metabolism
- Nutrition
- Movement
- Excretion
- Growth
- Response
- Reproduction
True or False: Electron microscopes can be used to examine living material.
False
What are the two main types of electron microscopes?
- Transmission Electron Microscope (TEM)
- Scanning Electron Microscope (SEM)
What is resolution in microscopy?
The minimal distance between two points at which they can still be distinguished as two
What is a disadvantage of electron microscopy?
Only provides black and white images and requires dead specimens
What is freeze fracture electron microscopy?
A technique that involves rapid freezing and fracturing a specimen for observation
What is cryogenic electron microscopy used for?
To analyze proteins and their structures at low temperatures
What are fluorescent stains?
Dyes that combine with specific cellular components and fluoresce under UV light
What is immunofluorescence?
A technique using antibodies linked with dyes to detect specific proteins
