Cells Flashcards
(96 cards)
What does the endosymbiotic theory state?
Some organelles in eukaryotic cells were once prokaryotic microbes
This theory explains the origin of mitochondria and chloroplasts.
What is believed to be the first eukaryotic cell?
An amoeba-like cell that obtained nutrients by phagocytosis
What are the two key eukaryotic organelles believed to be descendants of endosymbiotic eukaryotes?
- Mitochondria
- Chloroplasts
How did chloroplasts arise?
From photosynthetic bacteria
What is a significant similarity between mitochondria and chloroplasts?
Both are double-membraned organelles
What type of DNA do mitochondria and chloroplasts contain?
Circular DNA
How do mitochondria replicate?
By simple fission, similar to bacterial cells
What evidence supports the endosymbiosis theory?
Mitochondria and chloroplasts are the same size as prokaryotic cells and divide by binary fission
What is a defining feature of prokaryotic cells?
They lack membrane-bound organelles
What are the two fundamental types of cells?
- Prokaryotic cells
- Eukaryotic cells
What component of the cell is responsible for holding its components and giving it shape?
Cytoplasm
Fill in the blank: The ______ is the outer covering separating the cell’s interior from the surrounding environment.
plasma membrane
What are the four common components of all cells?
- Plasma membrane
- Cytoplasm
- DNA
- Ribosome
What is the function of ribosomes?
Site of protein synthesis
What is the function of the nucleus
The nucleus is the control center of a cell where genetic information (DNA) is stored.
What does the Golgi apparatus do?
Forms Lysozymes, processes enzymes and proteins to be secreted from the cell.
What is the primary structure that differentiates plant cells from animal cells?
Cell wall
What is the shape of animal cells?
Round (irregular shape)
What is the shape of plant cells?
Rectangular (fixed shape)
What organelles are present in both plant and animal cells?
- Mitochondria
- Endoplasmic reticulum
- Ribosomes
- Golgi apparatus
- Cytoplasm
What is one function of the cell wall in plant cells?
Provides mechanical support and prevents osmotic bursting
What is the role of centrioles in cells?
Form spindle fibers during cell division
What are prokaryotic cells primarily composed of?
A single chromosome consisting of circular double-stranded DNA
What is the function of the capsule in bacteria?
Acts as a defense barrier against environmental factors