Biology Test 2 Chapter 4

Front 1

Light Microscope (LM)

Back 1

An optical instrument with lenses that bends visible light to magnify images and project them into a viewer's eye.

Front 2

Cell Theory

Back 2

All living things are composed of cells and all cells come from other cells.

Front 3

Electron Microscope

Back 3

A microscope that uses magnets to focus an electron beam through, or onto the surface of a specimen. It magnifies 100x better than a light microscope.

Front 4

Scanning Electron Microscope

Back 4

A microscope that uses an electron beam to study the surface details of a cell or other specimens.

Front 5

Transmission Electron Microscope

Back 5

A microscope that uses an electron beam to study the internal structure of thinly sectioned specimens

Front 6

Which type of microscope would you use to study (a) the changes in shape of a living human white blood cell; (b) the finest details of surface texture of a human hair; (c) the detailed structure of an organelle in a liver cell?

Back 6

(a) light microscope; (b) scanning electron microspoce: (c) transmission electron microscope.

Front 7

Plasma Membrane

Back 7

The membrane at the boundary of every cell that acts as a selective barrier to the passage of ions and molecules into and out of the cell; consists of a phospholipid bilayer with embedded proteins.

Front 8

Prokaryotic Cells

Back 8

A type of cell lacking a membrane-enclosed nucleus and other membrane-enclosed organelles.

Front 9

Eukaryotic Cells

Back 9

A cell that has a membrane enclosed nucleus and membrane enclosed organelles.

Front 10

Cytosol

Back 10

The semifluid portion of the cytoplasm

Front 11

Chromosomes

Back 11

A gene-carrying structure found in the nucleus of a eukaryotic cell and most visible during mitosis and meiosis; also, the main gene-carrying structure of a prokaryotic cell. A chromosome consists of one very long DNA molecule and associated proteins.

Front 12

Ribosomes

Back 12

A cell structure consisting of RNA and protein organized into two subunits and functioning as the site of protein synthesis in the cytoplasm. In eukaryotic, the ribosomal subunits are constructed in the nucleolus

Front 13

Cytoplasm

Back 13

The contents of a eukaryotic cell between the plasma membrane and the nucleus; consists of a semifluid medium and organelles; can also refer to the interior of a prokaryotic cell.

Front 14

Nucleoid

Back 14

A non-membrane-bounded region in a prokaryotic cell where the DNA is concentrated.

Front 15

Flagella

Back 15

A long cellular appendage specialized for locomotion. The flagella of prokaryotes and eukaryotes differ in both structure and function. Like cilia, eukaryotic flagella have a "9+2" arrangement of microtubules covered by the cell's plasma membrane.

Front 16

List three features that are common to prokaryotic and eukaryotic cells. List three features that differ.

Back 16

Both types of cells have plasma membranes, chromosomes containing DNA, and ribosomes,

Prokaryotic cells are smaller, do no have a nucleus that housed their DNA or other membrane-enclosed organelles, and have smaller, somewhat different ribosomes.

Front 17

Organelles

Back 17

A membrane-enclosed structure with a specialized function within a cell.

Front 18

Cellular Metabolism

Back 18

All the chemical activities of a cell.

Front 19

Identify the structures in a plant cell that are not present in the animal cells.

Back 19

Chloroplast, central vacuole, cell wall, and plasmodesmata.

Front 20

Chromatin

Back 20

The complex of DNA and proteins that make up eukaryotic chromosomes; often used to refer to the diffuse, very extended form taken by chromosomes when a cell is not dividing.

Front 21

Nuclear Envelope

Back 21

A double membrane that encloses the nucleus, perforated with pores that regulate traffic with the cytoplasm.

Front 22

Nucleolus

Back 22

A structure within the nucleus where ribosomal RNA is made and assembled with the proteins imported from the cytoplasm to make ribosomal subunits.

Front 23

Describe the processes that occur in the nucleus.

Back 23

DNA is copied and passed on to daughter cells in cell division; rRNA is made and ribosomal subunits assembled; protein-making instructions in DNA are transcribed into mRNA

Front 24

What role do ribosomes play in carrying out the genetic instructions of a cell?

Back 24

Ribosomes synthesize proteins according to the instructions of messenger RNA, which was transcribed from DNA in the nucleus.

Front 25

Which structure includes all others in the list: rough ER, smooth ER, endomembrane system, nuclear envelope?

Back 25

Endomembrane system

Front 26

Endomembrane System

Back 26

A network of membranes inside and surrounding a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles.

Front 27

Vesicles

Back 27

A sac made of mebrane in the cytoplasm of a eukaryotic cell.

Front 28

Endoplasmic Reticulum (ER)

Back 28

An extensive membranous network in a eukaryotic cell, continuous with the outer nuclear membrane and composed of ribosome-studded and ribosome-free regions.

Front 29

Smooth Endoplasmic Reticulum

Back 29

The portion of the endoplasmic reticulum that lacks ribosomes.

Front 30

Rough Endoplasmic Reticulum

Back 30

That portion of the endoplasmic reticulum with ribosomes attached that make membrane proteins and secretory proteins.

Front 31

Explain why we say that endoplasmic reticulum is a biosynthetic workshop.

Back 31

The ER produces a variety of molecules, including phospholipids for cell membranes, steroid hormones, and proteins (synthesized by bound ribosomes) for membranes, other organelles, and secreted to the cell

Front 32

What is the relationship of the Golgi apparatus to the ER in a protein-secreting cell?

Back 32

The Golgi receives the transport vesicles budded from the ER that contain proteins synthesized by bound ribosomes. The Golgi finishes processing the proteins and dispatches vesicles to the plasma membrane, where the proteins are secreted.

Front 33

Glycoprotein

Back 33

A protein with one or more short chains of sugars attached to it.

Front 34

Transport Vesicle

Back 34

A small membraneous sac in a eukaryotic cell's cytoplasm carrying molecules produce by the cell. The vesicle buds from the endoplasmic reticulum or Golgi and eventually fuses with another organelle or the plasma membrane, eventually releasing its contents.

Front 35

Golgi Apparatus

Back 35

An organelle in eukaryotic cells consisting of stacks of membranous sacs that modify, store, and ship products of the endoplasmic reticulum.

Front 36

Lysosome

Back 36

A digestive organelle in eukaryotic cells; contains hydrolytic enzymes that digest engulfed food or damaged organelles.

Front 37

How is lysosome like a recycling center?

Back 37

It breaks down damaged organelles and recycles their molecules.

Front 38

Vacuoles

Back 38

A membrane-enclosed sac that is part of the endomembrane system of a eukaryotic cell and has diverse functions in different kinds of cells.

Front 39

Is a food vacuole part of the endomembrane system?

Back 39

Yes; it forms by pinching in from the plasma membrane, which is part of the endomembrane system.

Front 40

Peroxisomes

Back 40

An organelle containing enzymes that transfer hydrogen atoms from various substrates to oxygen, producing and then degrading hydrogen peroxide.

Front 41

How do transport vesicles help tie together the endomembrane system?

Back 41

transport vesicles move membranes and the substances they enclose between components of the endomembrane system.

Front 42

Mitochondria

Back 42

An organelle in eukaryotic cells where cellular respiration occurs. Enclosed by two membranes, it is where most of the cell's ATP is made.

Front 43

Mitochondrial Matrix

Back 43

The compartent of the mitochonrion enclosed by the inner membrane and containing enzymes and substrates for the citric acid cycle.

Front 44

What is cellular respiration

Back 44

A process that converts the chemical energy of sugars and other food molecules to the chemical energy of ATP.

Front 45

Chloroplasts

Back 45

An organelle found in plants and algae that absorbs sunlight and uses it to drive synthesis of organic compounds (sugars) from carbon dioxide and water

Front 46

Stroma

Back 46

A microscopic pore surrounded by guard cells in the epideris of a leaf. When stromata are open, CO2 enters a leaf, and H2O and O2 exit. A plant conserves water when its stroma are closed.

Front 47

Thylakoids

Back 47

A flattened membranous sac inside a chloroplast. Thylakoid membranes contain chlorophyl and the molecular complexes of the light reactions of photosynthesis. A stack of thylakpids is called a granum.

Front 48

Granum

Back 48

A stack of thylakoids.

Front 49

Endosymbiont Theory

Back 49

The theory that mitochondria and chloroplasts originated as prokaryotic cells engulfed by an ancestral eukaryotic cell. The engulfed cell and its host cell then involved into a single organism.

Front 50

The Cytoskeleton

Back 50

A network of protein fibers in the cytoplasm of a eukaryotic cell; incudes microfilaments, intermidiate filaments, and microtubules.

Front 51

Microtubules (large)

Back 51

The thickest of the three main kinds of fibers making uo the cytskeleton if a eukaryotic cell; a holow tube made of globular proteins called tubulins; found in cilia and flagella.

Front 52

Centrosome

Back 52

A structure found in animal cells from which microtubules originate. It is important during cell division. A centrosome has two centrioles.

Front 53

Intermediate filaments

Back 53

an intermediate-sized protein fiber that is one of the three main kinds of fibers making up the cytoskeleton of eukaryotic cells. Intermediate filaments are ropelike. made of fibrous proteins.

Front 54

Microfilaments (small)

Back 54

The thinnest of the three main kinds of protein fibers making up the cytoskeleton of a eukaryotic cell; a solid, helical rod composed of the globular protein actin.

Front 55

Which component of the cytoskeleton is most important in (A) holding the nucleus in place within the cell' (b) guiding transport vesicles from the Golgi to the plasma membrane; (c) contracting muscle cells?

Back 55

(A) intermediate filaments; (B) microtubules; (C) Microfilaments

Front 56

Which membrane in a chloroplast appears to be the most extensive? Why might this be so?

Back 56

The thylakoid membranes contain chlorophyl for photosynthesis.

Front 57

Cilia

Back 57

A short cellular appengage specialized for locomotion or moving fluid past the cell, formed from a core of nine outer doublet microtubules and two single micrtotubluse (the 9+2 arrangement) covered by the cells plasma membrane.

Front 58

Extracellular Matrix

Back 58

The meshwork surrounding animal cells; consists of glycoproteins and polysaccharides. It is synthesized and secreted by cells.

Front 59

Integrins

Back 59

A transmembrane protein that interconnects the extracellular matrix and the cytoskeleton in animal cells.

Front 60

What is the difference between immunofluorescence microscopy and molecular cytochemistry?

Back 60

In the former, fluorescently labeled antibodies show the locations of specific molecules. In the latter, the molecules themselves are labeled, and their behavior within a living cell can be tracked

Front 61

Primary ciliary dyskinesia (PCD), also known as immotile cilia syndrome, is a fairly rare disease in which cilia and flagella are lacking motor proteins, PCD is characterized by recurrent respiratory tract infections and immotile sperm. How would you explain these seemingly unrelated symptoms?

Back 61

Without motor proteins, microtubules cannot bend, Thus cilia cannot cleanse the respiratory tract, and sperm cannot swim.

Front 62

A muscle ear injury would probably involve the rupture of which type of cell junction?

Back 62

anchoring junction

Front 63

Cell Wall

Back 63

A protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists; protects the cell and helps maintain its shape.

Front 64

Plasmodesmata

Back 64

An open channel in a plant cell wall that connects the cytoplasm of adjacent cells.

Front 65

Which animal Cell Junction is analogous to a plasmodesmata?

Back 65

A gap junction

Front 66

How do mitochondria, smooth ER, and the cytoskeleton all contribute to the contraction of a muscle cell?

Back 66

Mitochondria supply energy in the form of ATP. The smooth ER helps regulate contraction by the uptake and release of calcium ions. Microfilaments function in the actual contractile apparatus.

Front 67

The ultrastructure of a chloroplast is best studied using a

Back 67

transmission electron microscope

Front 68

The cells of an ant and an elephant are on average, the same small size; an elephant just has more of them. What is the main advantage of small cell size?

Back 68

small cells can better take up sufficient nutrients and oxygen to service their cell volume

Front 69

Which of the following clues would tell you whether a cell is prokaryotic or eukaryotic?

Back 69

whether or not the cell is partitioned by internal membranes.

Front 70

What is a major components of the plasma membrane of a plant cell?

Back 70

phospholipids

Front 71

What four cellular components are shared by prokaryotic and eukaryotic cells?

Back 71

DNA as genetic material, ribosomes, plasma membrane, and cytosol.

Front 72

Describe two different ways in which cilia can function in organisms

Back 72

Cilia may propel a cell through its environment or sweep a fluid environment past the cell.

Front 73

in which cell would you find the most lysosomes?

Back 73

white blood cells that engulf bacteria

Front 74

in which cell would you find the most smooth ER?

Back 74

Ovarian cell that produces estrogen.

Front 75

in which cell would you find the most rough ER?

Back 75

a pancreatic cell that secretes digestive enzymes.

Front 76

in which cell would you find the most mitochondria?

Back 76

muscle cell in the thigh of a long distance runner.

Front 77

in what ways do the internal membranes of a eukaryotic cell contribute to the functioning of the cell

Back 77

different conditions and conflicting processes can occur simultaneously within separate, membrane-enclosed compartments. Also, there is increased area for membrane-attached enzymes that carry out metabolic processes.

Front 78

Describe the structure of the plasma membrane of an animal cell. What would be found directly inside and outside the membrane?

Back 78

The plasma membrane is a phospholipid bilayer with the hydrophilic heads facing the aqueous environment on both sides and the hydrophobic fatty acid tails mingling in the center of the membrane. Proteins are embedded in and attached to this membrane. microfilaments form a three-dimensional network just inside the plasma membrane. the extracellular matrix outside the membrane is composed largely of glycoproteins, which may be attached to membrane proteins called integrins. integrins can transmit information from the EMC to microfilaments on the other side of the membrane.

Front 79

describe the pathway of the protein hormone insulin from its gene to its export from a cell of your pancreas.

Back 79

An mRNA molecule is transcribed from the gene for insulin and moves into the cytosol. There it joins with a ribosome that becomes attached to the outside of the rough ER. The ribosome produces a polypeptide that is threaded into the ER compartment. The polypeptide folds up and may be modified within the ER. it is then packaged into a transport vesicle. The vesicle joins with a Golgi sac, and the protein may be further modified during its journey through the Golgi apparatus. A transport vesicle pinches off fro the Shipping face of the Golgi and fuses with he plasma membrane, secreting insulin from the cell.