What are the major parts of the cell
Plasma membrane
Cytoplasm
Organelles
Inclusions
Cells
The basic living, structural, functional units of the body
The human body has about 100 trillion cells 200 different cell types with a variety of shape, sizes and function
Plasma membrane
Fluid mosaic lipid bilayer (phospholipids, cholesterol, and glycolipids) studded with proteins
It surrounds the cytoplasm
Protects cellular components, makes contact with other cells, contains channels, transporters, receptors, enzymes, cell identity markers, linker proteins
Mediates the entry and exit of substances
Cytoplasm
Cellular contents between the plasma membrane and nucleus
Site of all intracellular activities except those occurring in the nucleus
Made up of cytosol, organelles and inclusions
Liquid part and organelles except the nucleus
Cytosol
Contains Microfilaments, intermediate filaments and microtubules
Fluid in which many of the metabolic reactions occur
Cytoskeleton maintains shape and general organization of cellular components
Responsible for cellular movement
It is part of the cytoplasm
Nucleus
Largest organelle
Contains DNA Nuclear envelope (double membrane) Nuclear pores Nucleolus
Nuclear pores control the movement of substances between the nucleus and cytoplasm, nucleoli produce ribosomes
Ribosomes
Not membrane bound
Synthesize in the nucleolus
Made up of ribosomal RNA and proteins
Functions if protein synthesis (translation)
There are free ribosomes(cellular proteins in cytosol) and er bound ribosomes ( membrane or secreted proteins)
Endoplasmic reticulum
Membranous network of flattened sacs or tubules
Extends from Nuclear envelope
Provides a surface for chemical reactions
Rough er: synthesizes glycoproteins and phospholipids that’s are transferred to cellular organelle, inserted in plasma membrane or secreted during exocytosis
Smooth er: synthesizes lipids and steroids, detoxifies or inactivates drugs, stores and release calcium ions in muscle cells
Golgi complex
Discovered by Camillo Golgi
Packaging, modification and transport of protein and lipids from er
Creates secondary vesicles and lysosomes
Lysosomes
Created by the golgi
Contain digestive enzymes (hydrolytic enzymes)
High acid low ph inside
Digests worn out organelles
Mitochondria
The power house of the cell Makes energy ATP Double membrane with enzymes on the inner one Cellular respiration They are self replicating Have their own DNA in circular form They are similar to prokaryotic cells We get them from our mother Has inner folding a called Cristae to increase surface area for cellular respiration Plays a role in apoptosis
Cytoskeleton
Microfilaments
Intermediate filaments
Microtubules
Microfilaments
Concentrated near the plasma membrane
Composed of myosin and actin
Functions are movement and mechanical support
Intermediate filaments
Size is in between Microfilaments and microtubules
Anchor organelles and anchor cells to one another
Found in parts of cells subject to mechanical stress
Exceptionally strong
Microtubules
Largest of cytoskeleton components
They are long unbranched hollow tubes composed mainly of the protein tubulin
Play a role in cell division
Movement of cilia and flagella
Membrane lipids
Phospholipids make up 75% (lipid bilayer)
glycolipids- 5% (self recognition)
Cholesterol- 20% (maintains fluidity and integrity)
Centrosome and centrioles
Centrosome - located near the nucleus, consists of two components a pair of centriole and pericentriolar material
Centrioles - are cylinder structure each composed of nine clusters of three microtubules arranged in a circular pattern
Net diffusion
Passive transport
Movement of molecules from high to low
Facilitated diffusion.
Movement of molecules from high to low
Transport molecule is uses
Passive transport
Osmosis
Movement of solvent (water) from high to low
Passive transport
Filtration
Mechanical/hydrostatic pressure
Passive transport
Primary active transport
Molecule mover hydrolyzes ATP
Low to high
Secondary active transport
Molecule mover does not hydrolyze ATP
Uses gradient created by primary active transport
Vesicular transport
Uses vesicles
Endocytosis (phagocytosis, Pinocytosis and receptor mediated endocytosis)
Exocytosis