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• #32: Figure: 05.2 Title: A generalized prokaryotic cell Caption: A generalized prokaryotic cell.
• #33: Figure: 05.3 Title: A generalized animal cell Caption: A generalized animal cell.
• #34: Figure: 05.4 Title: A generalized plant cell Caption: A generalized plant cell.
• #35: Figure: 05.5 Title: The nucleus Caption: (a) The nucleus is bounded by a double outer membrane. Inside are chromatin (chromosomes in an uncondensed state) and a nucleolus, which contains DNA coding for ribosomal RNA, ribosomes in various stages of synthesis, and associated proteins. (b) An electron micrograph of a yeast cell that has been frozen and broken open to reveal its internal structures. The large nucleus, with nuclear pores penetrating its nuclear membrane, is clearly visible.
• #36: Figure: 05.5a Title: The nucleus Caption: The nucleus is bounded by a double outer membrane. Inside are chromatin (chromosomes in an uncondensed state) and a nucleolus, which contains DNA coding for ribosomal RNA, ribosomes in various stages of synthesis, and associated proteins.
• #37: Figure: 05.5b Title: The nucleus Caption: An electron micrograph of a yeast cell that has been frozen and broken open to reveal its internal structures. The large nucleus, with nuclear pores penetrating its nuclear membrane, is clearly visible.
• #38: Figure: 05.6 Title: Chromosomes Caption: Chromosomes, seen here in a light micrograph of a dividing cell (on the right) in an onion root tip, are the same material (DNA and proteins) as the chromatin seen in nondividing cells adjacent to it, but in a more compact state.
• #39: Figure: 05.8a Title: Endoplasmic reticulum Caption: There are two types of endoplasmic reticulum: rough ER, coated with ribosomes, and smooth ER, without ribosomes. Although in electron micrographs the ER looks like a series of tubes and sacs, it is actually a maze of folded sheets and interlocking channels. In many cells the rough and smooth ER are thought to be continuous, as depicted in the drawing. Ribosomes (black) stud the cytoplasmic face of the rough ER membrane.
• #40: Figure: 05.8b Title: Rough endoplasmic reticulum Caption: Rough endoplasmic reticulum.
• #41: Figure: 05.8c Title: Smooth endoplasmic reticulum Caption: Smooth endoplasmic reticulum.
• #42: Figure: 05.9 Title: The Golgi complex Caption: The Golgi complex is a stack of flat membranous sacs derived from the endoplasmic reticulum. Vesicles constantly bud off from and fuse with the Golgi and ER, transporting material from the ER to the Golgi and back again, and from the Golgi to plasma membrane, lysosomes, and vesicles. Vesicles join the Golgi on one face and leave the Golgi from its opposite face.
• #43: Figure: 05.9a Title: The Golgi complex Caption: The Golgi complex is a stack of flat membranous sacs derived from the endoplasmic reticulum. VEsicles constantly bud off from and fuse with the Golgi and ER, transporting material from the ER to the Golgi and back again, and from the Golgi to plasma membrane, lysosomes, and vesicles. Vesicles join the Golgi on one face and leave the Golgi from its opposite face.
• #44: Figure: 05.9b Title: The Golgi complex Caption: The Golgi complex is a stack of flat membranous sacs derived from the endoplasmic reticulum. VEsicles constantly bud off from and fuse with the Golgi and ER, transporting material from the ER to the Golgi and back again, and from the Golgi to plasma membrane, lysosomes, and vesicles. Vesicles join the Golgi on one face and leave the Golgi from its opposite face.
• #45: Figure: 05.10 Title: The flow of membrane within the cell Caption: Membrane is synthesized by the endoplasmic reticulum. 1) Some of the membrane moves inward to form new nuclear envelope, some moves outward to form 2) smooth ER and 3) Golgi membrane. From the Golgi, membrane moves to form 4) new plasma membrane and 5) membrane surrounding other organelles such as lysosomes. Some proteins synthesized in the rough ER are modified in the smooth ER and travel in vesicles to the Golgi, where they are further modified and sorted. Some of these proteins are packaged in vesicles bound for the plasma membrane, where they will be 6) secreted from the cell, and some are packaged in lysosomes surrounded by membrane from the Golgi. Lysosomes may fuse with food vacuoles 7), allowing intracellular digestion of food particles.
• #46: Figure: 05.11 Title: Contractile vacuoles Caption: Many freshwater protists contain contractile vacuoles. (a) Water constantly enters the cell by osmosis. In the cell, water is taken up by collecting ducts and drains into the central reservoir of the vacuole. (b) When full, the reservoir contracts, expelling the water through a pore in the plasma membrane.
• #47: Figure: 05.12 Title: The central vacuole and turgor pressure in plant cells Caption: The central vacuole and turgor pressure in plant cells.
• #48: Figure: 05.13 Title: A mitochondrion Caption: Mitochondria consist of a pair of membranes enclosing two fluid compartments, the intermembrane compartment between the outer and inner membranes and the matrix within the inner membrane. The outer membrane is smooth, but the inner membrane forms deep folds called cristae. Mitochondria are the site of aerobic metabolism.
• #49: Figure: 05.13a Title: A mitochondrion Caption: Mitochondria consist of a pair of membranes enclosing two fluid compartments, the intermembrane compartment between the outer and inner membranes and the matrix within the inner membrane. The outer membrane is smooth, but the inner membrane forms deep folds called cristae. Mitochondria are the site of aerobic metabolism.
• #50: Figure: 05.13b Title: A mitochondrion Caption: Mitochondria consist of a pair of membranes enclosing two fluid compartments, the intermembrane compartment between the outer and inner membranes and the matrix within the inner membrane. The outer membrane is smooth, but the inner membrane forms deep folds called cristae. Mitochondria are the site of aerobic metabolism.
• #51: Figure: 05.14 Title: A chloroplast Caption: Chloroplasts are surrounded by a double membrane, although the inner membrane is not usually visible in electron micrographs. Semifluid stroma are enclosed by the inner membrane; stroma contain embedded stacks of sacs, collectively referred to as grana. The individual sacs of the grana are called thylakoids. Chlorophyll is embedded in the membranes of the thylakoids.
• #52: Figure: 05.14a Title: A chloroplast Caption: Chloroplasts are surrounded by a double membrane, although the inner membrane is not usually visible in electron micrographs. Semifluid stroma are enclosed by the inner membrane; stroma contain embedded stacks of sacs, collectively referred to as grana. The individual sacs of the grana are called thylakoids. Chlorophyll is embedded in the membranes of the thylakoids.
• #53: Figure: 05.14b Title: A chloroplast Caption: Chloroplasts are surrounded by a double membrane, although the inner membrane is not usually visible in electron micrographs. Semifluid stroma are enclosed by the inner membrane; stroma contain embedded stacks of sacs, collectively referred to as grana. The individual sacs of the grana are called thylakoids. Chlorophyll is embedded in the membranes of the thylakoids.
• #54: Figure: 05.15 Title: A plastid Caption: Plastids, found in the cells of plants and photosynthetic protists, are organelles surrounded by a double outer membrane. Chloroplasts are the most familiar plastids; other types store various materials, such as the starch filling these plastids in potato cells.
• #55: Figure: 05.16 Title: The cytoskeleton Caption: Eukaryotic cells are given shape and organization by the cytoskeleton, which consists of three types of proteins: microtubules, intermediate filaments, and microfilaments.
• #56: Figure: 05.17 Title: Cilia and flagella Caption: Both cilia and flagella contain microtubules arranged in an outer ring of nine fused pairs of microtubules surrounding a central unfused pair (a 9+2 arrangement). The nine outer pairs have “arms” made of protein that interact with adjacent pairs to provide the force for bending. Cilia and flagella arise from basal bodies formed from centrioles located just beneath the plasma membrane. The fused pairs of microtubles arise from these basal bodies, which have nine fused triplets of microtubules and no central microtubules (“9+0”).
• #57: Figure: 5.03 Title: Components of the cytoskeleton Caption: Components of the cytoskeleton.
• #58: Figure: 05.18 Title: How cilia and flagella move Caption: (a) (left) Cilia usually “row” along, providing a force of movement parallel to the plasma membrane, just as oars provide movement parallel to the sides of a rowboat. Their movement resembles the arms of a swimmer doing the breast stroke. (right) SEM photo of cilia lining the trachea (which conducts air to the lungs); these cilia sweep out mucus and trapped particles. (b) (left) Flagella move in a wavelike motion, providing continuous propulsion perpendicular to the plasma membrane. In this way a flagellum attached to a sperm can move the sperm straight ahead. (right) A human sperm cell on the surface of a human egg cell.
• #59: Figure: 05.18ac Title: How cilia move Caption: (a) (left) Cilia usually “row” along, providing a force of movement parallel to the plasma membrane, just as oars provide movement parallel to the sides of a rowboat. Their movement resembles the arms of a swimmer doing the breast stroke. (right) SEM photo of cilia lining the trachea (which conducts air to the lungs); these cilia sweep out mucus and trapped particles.
• #60: Figure: 05.18bd Title: How flagella move Caption: (b) (left) Flagella move in a wavelike motion, providing continuous propulsion perpendicular to the plasma membrane. In this way a flagellum attached to a sperm can move the sperm straight ahead. (right) A human sperm cell on the surface of a human egg cell.