Cells Flashcards
Cell Theory
The cell is the basic structural and functional unit of the body
Cell
Smallest living unit in the human body
Eucaryotes
Plant and animal cells
Components of the (animal) Cell
Plasma membrane, cytoplasm and organelles
What is a Plasma membrane?
A cell membrane - barrier around outside
Define Cytoplasm?
Material between plasma membrane and the nuclear membrane; cell contents excluding nucleus
What is Cytosol?
The viscous gel like fluid creating the cytoplasm. Organelles are suspended in this and many small molecules dissolve in this (proteins, ions, enzymes)
What is an organelle?
Specialised intracellular structures of characteristic shape that carry out specific roles in the cell
Mitochondria
Intracellular organelle responsible for generating most of the ATP required for cellular operations; energy powerhouse
ATP= Adenosine Triphosphate; high energy compound
Lysosomes
Intracellular vesicle with digestive enzymes; acidic environment lysing wide variety of molecules.`
Ribosomes
Organelle; contains RNA; create (synthesise) proteins from amino acids
Nucleus
Core of cell; largest organelle; nuclear membrane with pores; 1 or more nucleolus; chromatin (DNA)
Nucleolus & Chromatin
Part of nucleus
DNA and more DNA. Our genetic make up
Endoplasmic Reticulum (ER)
Network of membraneous channels in cytoplasm of cell.
Function in intracellular transport, synthesis, storage, packaging and secretion.
Large surface area
Rough Endoplasmic Reticulum
Membraneous organelle studded with ribosomes; site of protein synthesis and storage
(bench full of tools; those tools being ribosomes)
Smooth Endoplasmic Reticulum
Membraneous organelle in which phospholipid, fatty acid and steroid synthesis and storage occur.
Golgi Aparatus (complex/body)
Processes and delivers lipids and proteins to plasma membrane for secretion.
(Packaging factory: wraps up, processes and sends to address, usually outside of the cell)
Flagella & Cilia
Structurally similar organelles
Flagella: used to propel cell through fluid like sperm
Cytoskeleton
Network of microtubules and microfilaments in the cytoplasm.
Responsible for movement of cell and movement of organelles and molecules within cell; supports shape of cell
Enzyme
A protein that catalyses a specific biochemical reaction.
Promote chemical reactions ( E.g. Breakdown of sugars)
Cell membrane (Plasma Membrane)
Thin (6-10nm) barrier separating internal components of cell from the exterior environment. It regulates the passage of substances into and out of the cell.
Fluid Mosaic model of membrane structure
Membrane is a bilayer; proteins floating in “sea” of lipids.
Membrane Proteins
enzymes, receptors, anchors, transporters
Diffusion
Passive molecular movement from and area of higher concentration to area of lower concentration.
Continual random (passive) movement of particles amongst each other. The way particles move inside and around cells in the absence of specific transport mechanisms.