parts of the cell. 4.4 eukaryotic cells are partitioned into functional compartments there are four...
TRANSCRIPT
Parts of the Cell
4.4 Eukaryotic cells are partitioned into functional compartments
• There are four life processes in eukaryotic cells that depend upon structures and organelles– Manufacturing– Breakdown of molecules– Energy processing– Structural support, movement, and communication
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4.4 Eukaryotic cells are partitioned into functional compartments
• Manufacturing involves the nucleus, ribosomes, endoplasmic reticulum, and Golgi apparatus
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4.4 Eukaryotic cells are partitioned into functional compartments
• Breakdown of molecules involves lysosomes, vacuoles, and peroxisomes– Breakdown of an internalized bacterium by a
phagocytic cell would involve all of these
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4.4 Eukaryotic cells are partitioned into functional compartments
• Energy processing involves mitochondria in animal cells and chloroplasts in plant cells
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4.4 Eukaryotic cells are partitioned into functional compartments
• Structural support, movement, and communication involve the cytoskeleton, plasma membrane, and cell wall
Copyright © 2009 Pearson Education, Inc.
Nucleoid
Ribosomes
Plasma membrane
Cell wall
Capsule
Flagella
Bacterialchromosome
Pili
Smooth endoplasmicreticulum
Roughendoplasmicreticulum
CYTOSKELETON:
NUCLEUS:Nuclear envelope
Chromosomes
Nucleolus
Ribosomes
Golgiapparatus
Plasma membrane
Mitochondrion
Peroxisome
Centriole
Lysosome
Microtubule
IntermediatefilamentMicrofilament
Smooth endoplasmicreticulum
Rough endoplasmicreticulum
CYTOSKELETON:
NUCLEUS:
Nuclear envelope
Chromosome
NucleolusRibosomes
Golgiapparatus
Plasma membrane
Mitochondrion
Peroxisome
Cell wall
Central vacuoleMicrotubule
Intermediatefilament
Microfilament
Cell wall ofadjacent cell
Chloroplast
Plasmodesmata
Hydrophilic head
Hydrophobic tails
Symbol
Phosphategroup
Hydrophilic heads
Hydrophobic tails
Proteins
Hydrophobic region ofprotein
Inside cell Hydrophilic region ofprotein
Outside cell
NucleusDouble-layer membrane with pores. Connected to ER.Ribosomes made in a part called the nucleolus.
Two membranes ofnuclear envelope Nucleus
Nucleolus
Chromatin
Pore
Endoplasmicreticulum
Ribosomes
4.9 The endoplasmic reticulum is a biosynthetic factory
• There are two kinds of endoplasmic reticulum—smooth and rough
• Smooth ER lacks attached ribosomes• Rough ER lines the outer surface of membranes
– They differ in structure and function– However, they are connected
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Smooth ER
Nuclearenvelope
Ribosomes
Rough ER
4.9 The endoplasmic reticulum is a biosynthetic factory
• Smooth ER is involved in a variety of diverse metabolic processes (ex: synthesis of many types of lipids)
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4.9 The endoplasmic reticulum is a biosynthetic factory
• Rough ER makes additional membrane for itself and proteins destined for secretion (these proteins are transported in vesicles)
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Transport vesiclebuds off
Secretoryproteininside trans-port vesicle
Glycoprotein
Polypeptide
Ribosome
Sugarchain
Rough ER
1
2
3
4
Golgi
Receives proteins in vesicles from the ER.Modifies proteins- adds sugar chains to “mark” them for a certain destination.Puts the proteins back into vesicles and sends them out.
4.11 Lysosomes are digestive compartments within a cell
• A lysosome is a membranous sac containing digestive enzymes– The enzymes and membrane are produced by the ER
and transferred to the Golgi apparatus for processing– The membrane serves to safely isolate these potent
enzymes from the rest of the cell
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4.11 Lysosomes are digestive compartments within a cell
• One of the several functions of lysosomes is to remove or recycle damaged parts of a cell– The damaged organelle is first enclosed in a
membrane vesicle– Then a lysosome fuses with the vesicle, breaking
down the damaged organelle
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Animation: Lysosome Formation
Vacuoles
• Functions: storage, maintaining water balance, holding pigments, etc.
• Membrane-bound.
Nucleus
Chloroplast
Centralvacuole
Nucleus
Contractilevacuoles
Mitochondria
• Convert sugar (glucose) into ATP (adenosine triphosphate)- small energy packets. This is called cellular respiration.
• Have two membranes (inner and outer)
Mitochondrion
Intermembranespace
Innermembrane
Cristae
Matrix
Outermembrane
Chloroplasts
• Use the sun’s energy to create glucose from carbon dioxide and water (photosynthesis)
Chloroplast
Stroma
Inner and outermembranes
Granum
Intermembranespace
Engulfing ofphotosyntheticprokaryote
Chloroplast
Mitochondrion
Somecells
Host cell
Mitochondrion
Host cell
Engulfing of aerobicprokaryote
4.17 The cell’s internal skeleton helps organize its structure and activities
• The cytoskeleton is composed of three kinds of fibers– Microfilaments (actin filaments) support the cell’s
shape and are involved in motility– Intermediate filaments reinforce cell shape and
anchor organelles– Microtubules (made of tubulin) shape the cell and
act as tracks for motor protein
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VesicleATP
Receptor for motor protein
Microtubuleof cytoskeleton
Motor protein (ATP powered)
(a)
Microtubule Vesicles
(b)
0.25 µm