Cell Structure and Function
Cell size comparison Animal cell Bacterial cell
What jobs do cells have to do for an organism to live Gas exchange CO 2 & O 2 Eat (take in & digest food) Make energy ATP Build macromolecules proteins, carbohydrates, lipids, nucleic acids Remove wastes Control internal conditions (homeostasis) Respond to external environment Build more cells growth, repair, reproduction & development
Cell Membrane All Cells! Lipid bilayer embedded with proteins controls what enters or leaves cell O 2,CO 2, food, H 2 O, nutrients, waste recognizes signals from other cells allows communication between cells
Cytoplasm All Cells! Fluid in the cell Contains water, nutrients, and proteins Supports the cell structures
Cytoskeleton Not in Prokaryotes All Eukaryotes Thin tubes and filaments made of proteins Helps the cell: move, Keeps its shape Organizes its parts Think skeleton
Vacuoles Not in Prokaryotes Only in Plants and Protists Large membrane sac Store food, water, waste, and nutrients Plants have a large, central vacuole that fills with water and pushes against the cell wall causing the plant to stand upright
Vesicles Not in Prokaryotes All Eukaryotes Small membrane sac move material around the cell Like proteins, food, waste products, etc.
Lysosomes Not in Prokaryotes Animals and Some Protists Small membrane sac filled with digestive enzymes Digest food Clean up waste Recycle old parts
Mitochondria Not in Prokaryotes All Eukaryotes Outer membrane surrounding an folded inner membrane embedded with many proteins Makes ATP using the energy from glucose Cellular Respiration Glucose + O 2 ATP + CO 2 +H 2 0 Singular = Mitochondrion ATP
Chloroplast Not in Prokaryotes Only in Plants and Some Protists Double membrane surrounding thylakoids which contain the pigment chlorophyll (green) Photosynthesis to make glucose Sun light + CO 2 +H 2 0 Glucose + O 2
Cell Wall All Prokaryotes Fungi, Plants, and some Protists (Not Animals) Rigid Layer that lies outside the cell membrane Bacteria peptidoglycan (proteins and sugars) Plants cellulose Fungi chitin and support
Nucleus Not in Prokaryotes All Eukaryotes Nuclear membrane with nuclear pores Contains the nucleolus where ribosomes are made Filled with DNA Stores and protects the DNA
Ribosomes All Cells! Small structures made of proteins and RNA some float in cytoplasm some attach to ER Make proteins using instructions from the DNA
Rough Endoplasmic Reticulum A system of interconnected membrane folds/sacs embedded with ribosomes Usually found connected to the nucleus Not in Prokaryotes All Eukaryotes Package the proteins made by ribosomes into vesicles to be transported around the cell
Smooth Endoplasmic Reticulum A system of interconnected membrane tubes (with no ribosomes) Usually found with the Rough ER Builds lipids Breaks down toxins Makes vesicles Not in Prokaryotes All Eukaryotes
Golgi Apparatus Not in Prokaryotes All Eukaryotes Membrane folds/sacs Modifies, sorts, labels, packages, and ships proteins and lipids UPS store
nucleus DNA endoplasmic reticulum protein on its way! TO: RNA vesicle TO: ribosomes TO: vesicle Making Proteins protein Golgi apparatus TO: finished protein
*Centrioles* Not in Prokaryotes Only Animals and some Protists Two short cylinders made of proteins Organize the parts of the cytoskeleton that help with cell division
Cilia Not in Prokaryotes Only Animals and Some Protists Short, hair-like structures made of proteins covered in membrane that extend from the surface of the cell Help a cell move through a watery environment Or, help move air and fluids over the cell s surface Protist Video
Flagella Some Prokaryotes Some Animals and Some Protists Long, hair-like structures made of proteins covered in membrane that extend from the surface of the cell Moves the cell through its environment Singular = Flagellum
Plasmid Only Prokaryotes A small, extra ring of DNA Provides extra genetic information Can be swapped with other bacteria May carry antibiotic resistance genes
Capsule Some Prokaryotes Outer covering of sticky carbohydrates that bind to the cell wall Protects the cell from drying out and harsh chemicals Keeps bacteria from being broken down Helps bacteria stick to other cells
Pili Some Prokaryotes Short, thick, hair-like structures made of protein found on the surface of bacterial cells Help bacteria stick to other cells and surfaces Allow bacteria to share plasmids