What is the first principle of Cell Theory?
New cells come from preexisting cells
This principle emphasizes the continuity of cellular life.
What does Cell Theory state about cells?
- Cells are fundamental units of structure
- Cells are the fundamental unit of function and organization of all living things
- All cells contain hereditary information
- All energy flow occurs in the cell
These principles outline the essential roles of cells in biology.
True or false: According to Cell Theory, all cells contain hereditary information.
TRUE
This highlights the role of cells in genetic inheritance.
Fill in the blank: All energy flow occurs in the _______.
cell
This indicates that metabolic processes take place within cells.
What is the 9 + 2 arrangement in cell structure?
A structural organization of cilia and flagella consisting of nine doublet microtubules surrounding two central microtubules
This arrangement is characteristic of eukaryotic cilia and flagella.
What is autophagy?
The process by which cells degrade and recycle their own components
Autophagy is essential for cellular maintenance and homeostasis.
Define cell theory.
A fundamental concept in biology stating that all living organisms are composed of cells, and cells are the basic unit of life
Cell theory also includes the idea that all cells arise from pre-existing cells.
What is the function of the plasma membrane?
To protect the cell and regulate the movement of substances in and out of the cell
The plasma membrane is selectively permeable.
What is the function of chloroplasts?
To conduct photosynthesis in plant cells
Chloroplasts contain chlorophyll, which captures light energy.
What is cytoplasmic streaming?
The movement of the fluid substance (cytosol) within a cell
This process helps distribute nutrients and organelles throughout the cell.
What are ribosomes responsible for?
Protein synthesis
Ribosomes can be found bound to the endoplasmic reticulum or free in the cytoplasm.
What is the role of the Golgi apparatus?
To modify, sort, and package proteins and lipids for secretion or delivery to other organelles
The Golgi apparatus is often referred to as the cell’s ‘post office’.
What is the extracellular matrix?
A network of proteins and carbohydrates outside the cell that provides structural and biochemical support
The extracellular matrix is crucial for tissue and organ structure.
What is the function of mitochondria?
To produce ATP through cellular respiration
Mitochondria are known as the ‘powerhouses’ of the cell.
What is phagocytosis?
The process by which a cell engulfs solid particles to form an internal compartment called a phagosome
Phagocytosis is a form of endocytosis.
What are tight junctions?
Specialized connections between adjacent cells that prevent the passage of materials between them
Tight junctions are important for maintaining the integrity of epithelial layers.
What is the nucleus?
The membrane-bound organelle that contains the cell’s genetic material
The nucleus is often referred to as the control center of the cell.
What is the function of the cytoskeleton?
To provide structural support, shape, and facilitate movement within the cell
The cytoskeleton is composed of microfilaments, intermediate filaments, and microtubules.
What is dynamic instability in microtubules?
The rapid switching between growth and shrinkage of microtubules
This property is crucial for cellular processes such as mitosis.
What is cellulose?
A polysaccharide that forms the structural component of the cell wall in plants
Cellulose provides rigidity and strength to plant cells.
What are fimbriae?
Hair-like structures on the surface of some bacteria that help them adhere to surfaces
Fimbriae play a role in bacterial colonization.
What is the endoplasmic reticulum?
An organelle involved in the synthesis of proteins (rough ER) and lipids (smooth ER)
The rough ER is studded with ribosomes, while the smooth ER lacks them.
What is the nuclear envelope?
A double membrane that surrounds the nucleus and separates it from the cytoplasm
The nuclear envelope contains nuclear pores that regulate the passage of materials.
What is chromatin?
The complex of DNA and proteins that forms chromosomes within the nucleus
Chromatin exists in two forms: euchromatin (active) and heterochromatin (inactive).
