Cell Structure (Unit 1) - less important Flashcards
What are the three main points of the cell theory?
1) All living organisms are made of one or more cells. 2) The cell is the basic organizational unit of life. 3) All cells come from pre-existing cells
How can most diseases and disorders be explained?
: Most diseases and disorders can be explained by a defect at the cellular level
What constitutes the genetic material in prokaryotes and eukaryotes?
In prokaryotes, the genetic material is a single circular molecule of DNA. In eukaryotes, it is a double helix located in the nucleus, enclosed by a nuclear envelope
What is the significance of the cell size being small?
Cells are generally small because as size increases, the volume increases much more rapidly than the surface area, affecting efficiency
Describe the structure of the cell wall
The cell wall is found in plants, some bacteria, fungi, and protists. It is thicker, stronger, and more rigid than cell membranes, made up of cellulose, and perforated with many pores.
Cell wall purpose?
It protects cells from rupturing and allows cells to exchange material with the environment or communicate with other cells
What are the main components and functions of the nucleus?
The nucleus contains genetic material (DNA) and directs the activities of the cell. It is usually single but can vary, surrounded by a nuclear membrane with pores that control molecular movement. The nucleolus inside the nucleus makes ribosomes.
What is the role of the endoplasmic reticulum in a cell?
The endoplasmic reticulum transports molecules throughout the cell and is made up of membranes that act as channels or passageways.
Describe the main organelles made just of a membrane and their functions.
Vesicles transport and store materials inside or outside the cell. Lysosomes contain digestive enzymes. Vacuoles, especially large in plant cells, are used for storage.
What is the role of mitochondria and chloroplasts in cellular processes?
Mitochondria release energy from glucose through cellular respiration. Chloroplasts trap energy from the sun to make glucose through photosynthesis.
Describe the structure and functions of the cytoskeleton.
The cytoskeleton is a network of protein fibers supporting cell shape and anchoring organelles. It includes actin filaments for movement, microtubules which facilitate cell movement and are involved with centrioles in microtubule assembly, and intermediate filaments which are stable and do not break down easily.
What are the functions of the cell membrane and its importance in cellular activities?
The cell membrane controls what goes in and out of the cell, compartmentalizes cell components, and maintains the fluid mosaic model where proteins and lipids create a dynamic structure. It is crucial for processes such as transport, signaling, and structural integrity.
What are the roles of lipids and proteins in the cell membrane?
Lipids provide physical integrity and barrier functions, allowing the cell to maintain fluidity. Proteins transport materials, function as enzymes, trigger signals, and aid in attachment and recognition processes in the cell.
