Chapter 7

Question 1

plasma membrane

Answer 1

membrane that surrounds a cell, and selectively permeates molecules to cross

Question 2

morphology

Answer 2

shape and appearance of an organisms body and its component parts

Question 3

phylogeny

Answer 3

evolutionary history of a group of organisms

Question 4

chromosome

Answer 4

gene carrying structure consisting of a single long molecule of DNA and associated proteins

Question 5

gene

Answer 5

section of DNA that encodes information for building one or more related polypeptides or functional RNA molecules along with the regulatory sequences required for transcription

Question 6

nucleoid

Answer 6

in prokaryotic cells a dense centrally located region that contains DNA but is not surrounded by a membrane

Question 7

plasmids

Answer 7

small usually circular supercoiled DNA molecule independent of the cells main chromosomes in prokaryotic cells

Question 8

glycolipids

Answer 8

any lipid molecule that is covalently bonded to a carbohydrate group

Question 9

nuclear lamina

Answer 9

lattice like sheet of fibrous nuclear lamins, which are one type of intermediate filaments

Question 10

nucleolus

Answer 10

in eukaryotic cells, specialized structure in the nucleus where ribosomal RNA processing occurs and RNA subunits are assembled

Question 11

lumen

Answer 11

interior space of any hollow structure or organ

Question 12

cisternae

Answer 12

flattened membrane bound compartments that make up the golgi apparatus

Question 13

cytosol

Answer 13

fluid portion of the cytoplasm

Question 14

perixosomes

Answer 14

an organelle in eukaryotic cells that contains enzymes to oxidize fatty acids and other compounds like toxins rendering them harmless

Question 15

glyoxysomes

Answer 15

specialized type of peroxisomes found in plant cells and packed with enzymes to process the products of photosynthesis

Question 16

autophagy

Answer 16

self eating-process of damaged organelles being enveloped in a membrane and transported to a lysosome

Question 17

pinocytosis

Answer 17

uptake by a cell of extracellular fluid by pinching of the plasma membrane to form small membrane bound vesicles, type of endocytosis

Question 18

differential centrifugation

Answer 18

process for separating components according to size and density by spinning a cell in a series of centrifuge runs

Question 19

pulse-chase experiment

Answer 19

type of experiment in which population of cells or molecules at a particular moment is marked by a means of a labeled molecule and then their fate is followed over time

Question 20

nuclear localization

Answer 20

short amino acid sequence that marks a protein for delivery to the nucleus

Question 21

ER signal sequence

Answer 21

short amino acid sequence that marks a polypeptide for transport to the ER where synthesis of the polypeptide occurs and the signal sequence removed

Question 22

glycosylation

Answer 22

addition of a carbohydrate group to a molecule

Question 23

glycoprotein

Answer 23

any protein covalently bonded to a carbohydrate group

Question 24

actin filaments

Answer 24

long fiber made of actin proteins, one of the three types of cytoskeletal fibers

Question 25

motor protein

Answer 25

class of proteins whose major function is to convert chemical energy of ATP into motion

Question 26

cytoplasmic streaming

Answer 26

directed flow of cytosol and organelles that facilitate s distribution of materials within some large plant cells an fungal cells. Occurs along actin filaments and powered by myosin

Question 27

cell crawling

Answer 27

form of cellular movement involving actin filaments in which the cell produces bulges that stick to the substrate and pull the cell forward

Question 28

nuclear lamins

Answer 28

intermediate filaments that make up the nuclear lamina layer

Question 29

dimers

Answer 29

association of two molecules which may be identical or different

Question 30

kinesin

Answer 30

any one of a class of motor proteins that use chemical energy of ATP to transport vesicles, particles or chromosomes along microtubules

Question 31

axoneme

Answer 31

structure found in eukaryotic cilia and flagella and is responsible for their motion , composed of two central microtubules surrounded by nine doublet microtubules

Question 32

basal body

Answer 32

structure of nine pairs of microtubules arranged in a circle at the base of eukaryotic cilia and flagella

Question 33

dynein

Answer 33

any one of the class of motor proteins that use ATP to move along an adjacent microtubule, responsible for the bending of cilia and flagella as well as chromosome movement during mitosis