Chapter 4: Evolutionary Origin of Cells and Their General Features

Question 1

What does the nucleus of a eukaryotic cell contain in respect to DNA?

Answer 1

chromosomes; which are formed of chromatin (a complex of DNA and proteins)

Question 2

What are the function of the smooth ER ?

Answer 2

metabolism, detoxification, calcium ion storage, & lipid synthesis and modification

Question 3

What is the function of rough ER ?

Answer 3

protein sorting and pairing, insertion of membrane proteins, and glycosylation

Question 4

What makes rough ER different then smooth ER ?

Answer 4

Rough ER has ribosomes connected to it and it is closer to the nucleus; smooth ER lacks ribosomes and is further away from the nucleus

Question 5

What is the function of the Golgi Apparatus?

Answer 5

protein sorting, protein processing (including glycosylation and proetolysis), and secretion

Question 6

What is the function of a lysosome ?

Answer 6

The break down of macromolecules (carbs, lipids, proteins, and nucleic acids.

found in animal cells ONLY, NOT plant cells

Question 7

What is the function of a vacuole?

Answer 7

storage and structure, regulates cell volume, and the degradation of macromolecules

Question 8

What is the function of a peroxisome.

Answer 8

break down nutrients (such as fats and amino acids) and toxins

Question 9

What are the two semiautonomous organelles? And what is the endosymbiosis theory?

Answer 9

Mitochondria and chloroplasts are the semiautonomous organelles. The theory states that they contain their own genetic material

Question 10

TRUE or FALSE: Mitochondria and Chloroplasts contain their own genetic material

Answer 10

TRUE

Question 11

What is the function of a sorting signal ?

Answer 11

they direct proteins to correct cellular destinations; located in eukaryotes

Question 12

What is the role of the Extracellular Matrix (ECM) in animal cells ?

Answer 12

Supports structure and organizes cell signaling

Question 13

The textbook covers the origin of cells. It mentions that there are 4 steps in this process. What are they?

Answer 13

1. nucleotides and amino acids were first
2. polymers formed (RNA, DNA, protein)
3. polymers became enclosed in membranes
4. polymers acquired properties of living cells

Question 14

Which hypothesis proposed that the Earth atmosphere facilitated the redox reactions required to form organic molecules?

Answer 14

the reducing atmosphere hypothesis

Question 15

The initial products of the Miller and Urey experiments were? (hint: reducing atmosphere hypothesis)

Answer 15

precursors to organic molecules

Question 16

Which hypothesis proposed that organic molecules present in meteorites, asteroids and comets reached the surface of Earth through collisions?

Answer 16

the extraterrestrial hypothesis

Question 17

Which hypothesis proposed that organic molecules may have originated in sea vents, where superheated water containing dissolved gases ad metal ions mixes with cold sea water.

Answer 17

the deep-sea vent hypothesis

Question 18

Simple organic molecules polymerized to form complex organic polymers during which stage in the origin of life?

Answer 18

second

Question 19

Which macromolecule forms the foundation for the structure and activities of living cells?

Answer 19

proteins

Question 20

The RNA world is a hypothetical period on Earth when RNA molecules performed what functions?

Answer 20

1) enzymatic catalysis and 2) genetic information

Question 21

An aggregate of prebiotically produced molecules and macromolecules with a boundary to separate its internal chemical environment from its surroundings is called?

Answer 21

a protobiont

Question 22

Protobionts may have existed in different forms. What is this image an example of? Label 1-2.

Answer 22

This image is an example of a liposome, which is what researches believe the protobionts may have existed as. 1) hollow sphere of phospholipid filled with water; 2) phospholipid bilayer

Question 23

RNA exhibits three key functions. What are they?

Answer 23

1. the capacity for self-replication
2. the ability to perform catalyst functions
3. the ability to store information in its nucleotide sequence

Question 24

Why was DNA favored over RNA to store genetic information?

Answer 24

1) DNA is more stable
2)RNA can perform more functions if it did not have to store information

Question 25

What type of cell is this? Label the diagram 1-8.

Answer 25

This is a prokaryotic cell. 1) ribosomes, 2) cytoplasm, 3) pili, 4) flagella, 5) glycocalyx, 6) cell wall, 7) plasma membrane, 8) nucleoid

Question 26

What type of cell is this? Label 1-16.

Answer 26

This is an animal cell. 1) centrosome, 2) nuclear pore, 3) nucleus, 4) nuclear envelope, 5) lysosome, 6) nucleolus, 7) ribosome, 8) chromatin, 9) plasma membrane, 10) cytosol, 11) golgi, 12) peroxisome, 13) cytoskeleton, 14) mitchondria, 15) smooth ER, 16) rough ER

Question 27

What kind of cell is this? Label 1-17.

Answer 27

Plant cell. 1) central vacuole, 2) nuclear envelope, 3)nucleus, 4) nuclear pore, 5) ribosomes, 6) smooth ER, 7) rough ER, 8) plasma membrane, 9) cell wall, 10) peroxisome, 11) golgi, 12) cytoskeleton, 13) chloroplast, 14) mitochondria, 15) cytosol, 16) nucleolus, 17) chromatin

Question 28

Some organelle form when aggregated solutes, such as proteins and RNA molecules, separate from the bulk solvent and form a complex. What are these called? And what is this process called?

Answer 28

droplet organelles; liquid liquid phase

Question 29

The sum of the chemical reactions by which cells produce the materials and utilize energy that is necessary to sustain life is defined as?

Answer 29

metabolism

Question 30

What is the function of the cytoskeleton and what are the 3 different types of protein filaments that make the network of the cytoskeleton?

Answer 30

The cytoskeleton provides cell shape, organization and movement. The three types of filaments are microtubules, intermediate filaments, and actin filaments.

Question 31

Label 1-3 based on the information provided in the table.

Answer 31

1) microtubules 2) intermediate filaments 3) actin filaments

Question 32

What types of movements are promoted by motor proteins?

Answer 32

1) movement of cargo 2) movement of filament 3) bending of filament

Question 33

Label a, b, and c. Label 1-3.

Answer 33

a) movement of cargo b) movement of filament c) bending of filament 1) cargo 2) mictrotubule 2) actin filament

Question 34

T or F: Flagella are usually longer than cilia and present singly or in pairs

Answer 34

TRUE; cilia are shorter and tend to be numerous and cover all or part of the cell surface

Question 35

Where are ribosomes formed?

Answer 35

Inside the nucleolus

Question 36

What is the function of mitochondria?

Answer 36

to make ATP

Question 37

Which organelle is an example of a droplet organelle?

Answer 37

the nucleolus

Question 38

The complete set of genetic material present in a cell or organism is called its?

Answer 38

genome

Question 39

List the organelles that are all part of the endomembrane system.

Answer 39

ER, golgi, lysosomes, vacuoles, peroxisomes, and nuclear envelope.

Question 40

The disconnected organelles of the endomembrane system pass materials to each other via?

Answer 40

vesicles

Question 41

T or F: Mitochondria create energy.

Answer 41

FALSE: they convert chemical energy stored in bonds of sugars, fats and amino acids into chemical energy stored in the bonds of ATP.

Question 42

What is this an image of? Label 1-5.

Answer 42

This is a mitochondrion. 1) outer membrane, 2) intermembrane space, 3) inner membrane, 4) mitochondrial matrix, 5) cristae

Question 43

The complex of DNA and proteins in a eukaryotic cell is referred to as?

Answer 43

chromatin

Question 44

In plant cells, what is the structure that provides mechanical support, maintains cell shape, prevents cells from bursting due to water entry, and helps to determine the direction of cell growth?

Answer 44

the cell wall

Question 45

The organelles that contain acid hydrolyses used to break down various complex organic materials are the?

Answer 45

lysosomes

Question 46

The function of a chloroplast is to capture the light energy necessary for the synthesis of WHAT organic molecule in the process of photosynthesis?

Answer 46

glucose

Question 47

What is this diagram of? Label 1-6.

Answer 47

A chloroplast. 1) outer membrane, 2) inner membrane, 3) thylakoid membrane, 4) thylakoid lumen, 5) granum, 6) stroma

Question 48

What term describes a relationship between two different species in which the smaller species lives inside the larger one?

Answer 48

endosymbiosis

Question 49

The ECM is composed of two major macromolecules. What are they?

Answer 49

proteins and polysaccharides

Question 50

What is the function of proteins in the ECM?

Answer 50

provide strength and elasticity

Question 51

How do glycosaminoglycans protect cells from compression?

Answer 51

Their negative charge allows them to attract water, giving the ECM a gel-like quality

Question 52

How do cell walls of plants differ from the ECM of animals.

Answer 52

1) more rigid 2) thicker & stronger 3) can prevent osmotic lysis

Question 53

What is this a figure of? Label 1-8.

Answer 53

This is a close up of the membranes of the nuclear envelope. 1) nucleus, 2) chromatin in nucleus, 3) internal nuclear matrix, 4) inner membrane, 5) outer membrane, 6) nuclear lamina, 7) cytosol, 8) nuclear pore matrix

Question 54

What is this an image of? Label 1-3

Answer 54

This is a close up of the cell wall. 1) plasma membrane, 2) secondary cell wall, 3) primary cell wall

Question 55

What is the main component of the cell wall?

Answer 55

cellulose

Question 56

Plant cell wall polysaccharides are made of WHAT repeating molecules?

Answer 56

glucose

Question 57

Which cell wall is flexible and allows cells to increase in size? Which one provides strength?

Answer 57

The primary cell wall is flexible and allows cells to increase in size. The secondary cell wall provides strength.