Cells, tissues, cellular metabolism, transport Flashcards
(44 cards)
What are organelles?
Structures within the cytoplasm of a cell, each with a specific function.
What is the function of the cell membrane?
Separates the internal and external environment, regulates what exits and enters the cell, and senses external changes. It is semi-permeable.
What is the phospholipid bilayer?
Composed of hydrophilic heads and hydrophobic tails, with heads exposed to water and tails mingling together. Only allows substances that can dissolve in fat to pass through.
What can pass through the cell membrane by simple diffusion?
Very small, uncharged particles like oxygen and carbon dioxide, and small liquid soluble molecules like alcohol and steroids.
What is cytoplasm?
Comprised of the cytosol and all organelles in the cell.
What is cytosol?
A jelly-like fluid in the cell that supports and protects organelles. Most chemical reactions happen in the cytosol.
What is the nucleus?
Found in the center of the cell, it stores genetic information (DNA) and controls the functioning of the cell.
What is the role of mitochondria?
Site of cellular respiration (aerobic) where most ATP is produced.
What does the Golgi apparatus do?
Modifies and packages proteins.
What are centrioles?
Organized collections of microtubules that guide chromosome separation during meiosis or mitosis.
What is the endoplasmic reticulum?
A system of layers of folded membrane connected to the nuclear pores of the nucleus, involved in storing and transporting molecules.
What is the function of lysosomes?
Storage site to break down toxic molecules and bind to vesicles containing digestive enzymes.
What are ribosomes?
Not membrane-bound structures comprised of sub-units containing RNA and protein, responsible for protein synthesis.
What is the cytoskeleton?
A fibrous network inside the cell that anchors organelles, fixes cell shape, and allows movement of internal structures.
What is a flagellum?
A tail-like structure that allows cells to move, usually found in sperm cells.
What are cilia?
Hair-like projections that help move material across the surface of the cell.
What are inclusions?
Special molecules or structures specific to different cell types that contribute to their functions.
What limits the size of cells?
The surface area required to supply the needs of the volume; larger organisms are made up of many cells.
What are membrane channels?
Proteins that allow ions, water, and small molecules to pass through the cell membrane.
What are carriers in cell membranes?
Proteins that allow larger molecules and solid substances to pass through the cell membrane.
What is active transport?
Transport that requires energy and can move substances against a concentration gradient.
What is vesicular transport?
Transport of materials in bulk across the membrane in membrane-bound sacs.
What is endocytosis?
The process of bringing materials into cells.
What is exocytosis?
The process of expelling substances from the cell.
