Cell Components Flashcards
Nuclear membrane
Bilayer membrane
Two phospholipid layers
Allows nucleus to be contained/compartmentalized so it can function
Nuclear pores
Cross nuclear membrane
Allow selective transport of large molecules over 40 kDa (such as RNA and proteins)
Nucleolus
Responsible for ribosome assembly
Nucleus
Stores genetic information
Cytoplasm
Everything within a living cell
So everything besides nucleus and external membrane
Includes all other organelles plus the cytosol
Cytosol
Dense, gel like aqueous solution
Mitochondria
Two membranes (outer and inner) Outer membrane Inter membrane space Inner membrane Mitochondrial matrix = site of citric acid cycle Protons buildup in inter membrane Self replicating and have their own DNA
Lysosomes
Waste enters though endocytosis
Waste exits through autophagy
Contain enzymes that hydrolyze polymers
Kept at 4.5-5 pH
Endoplasmic Reticulum
Extends out from nuclear membrane in cisternae - tubes, double-membrane
Rough = section covered with ribosomes site of protein synth
Smooth = lipid metabolism, hormone production, detoxification, phospholipid production for cell
Golgi apparatus
Packages and modified synthesized proteins and send to destination
Composed of cisternae (double membrane)
Prep proteins for secretion
Peroxisomes
Contain peroxides
Break long chain lipids into medium lipids
Detoxify substances
Cytoskeleton
Provides structure to cell and helps cell move
Composed of microfilaments, microtubules, and intermediate filaments
Microfilaments
Two strands of actin polymers
Play role in cell motility, endocytosis and exocytosis
Contribute to cell cleavage in mitosis
Actin interacts with myosin during muscle contraction
Microtubules
Wider than filaments
Composed of alpha and beta tubulin which form a tubulin dimer
Often found in 9+2 structure (cilia and flagella)
Facilitate intercellular transport and make up mitotic spindles
Intermediate filaments
Broad category of proteins that provide structure
Involved in cellular adhesion
Ex: keratin
