Course Guide Chapter 5: Cell Structure and Function

Question 1

What is the difference between prokaryotic and eukaryotic cells in terms of nuclei?

Answer 1

Prokaryotic Cell: no nuclei Eukaryotic Cell: true nuclei

Question 2

What is the difference between prokaryotic and eukaryotic cells in terms of DNA?

Answer 2

Prokaryotic Cell: DNA in the nucleoid region Eukaryotic Cell: DNA within nucleus

Question 3

What is the difference between prokaryotic and eukaryotic cells in terms of endomembrane system?

Answer 3

Prokaryotic Cell: no endomembrane system Eukaryotic Cell: vast endomembrane system

Question 4

What is the difference between prokaryotic and eukaryotic cells in terms of organelles?

Answer 4

Prokaryotic Cell: no organelles Eukaryotic Cell: membrane-bound organelles

Question 5

What is the difference between prokaryotic and eukaryotic cells in terms of cell size?

Answer 5

Prokaryotic Cell: small cell size Eukaryotic Cell: large cell size

Question 6

What is the difference between prokaryotic and eukaryotic cells in terms of proteins?

Answer 6

Prokaryotic Cell: no proteins are attached to DNA Eukaryotic Cell: proteins (histones) are attached to DNA

Question 7

What is the function of the nucleolus?

Answer 7

organizing center for making ribsomes from ribosomal RNA and ribosomal proteins

Question 8

What is the function of the nuclear pores?

Answer 8

allow for movement of solutes in and out

Question 9

What is the function of the ribosomes?

Answer 9

synthesize proteins

Question 10

What is the function of the smooth ER?

Answer 10

synthesize lipids, carbohydrate metabolism, detoxification, stores Ca²⁺

Question 11

What is the function of the rough ER?

Answer 11

synthesizes membrane-bound proteins for secretion and modification; synthesizes membrane from phospholipids and membrane proteins

Question 12

What is the function of the golgi apparatus?

Answer 12

functions as the central receiving and dispatching center where proteins made in the ER arrive, are sorted out, packages into vesicles and shipped to target sites; modifies proteins

Question 13

What is the function of the lysosomes?

Answer 13

digests and excretes food

Question 14

What is the function of the peroxisome?

Answer 14

lipid degradation and detoxification of active oxygen species

Question 15

What is the function of the glyoxysomes?

Answer 15

facilitates breakdown of storage lipids in germinating seeds that store larger quantities of oils and lipids

Question 16

What is the function of the large central vacuole?

Answer 16

storage

Question 17

What is the function of the food vacuoles?

Answer 17

helps with ingestion

Question 18

What is the function of the contractile vacuoles?

Answer 18

help remove excess water from the cell

Question 19

What are similarities between mitochondria and chloroplast?

Answer 19

1. double membrane structure 2. have their own DNA and proteins 3. replicate autonomously 4. Import some proteins from the cytoplasm 5. Make ATP 6. used for evolutionary studies

Question 20

What are differences between mitochondria and chloroplast?

Answer 20

1. Mitochondria found in all higher eukaryotes; chloroplasts found in plants only 2. Mitochondria perform respiration; chloroplast perform photosynthesis and amino acid biosynthesis

Question 21

What is the difference between microtubules, microfilaments, and intermediate filaments in terms of what they are made of?

Answer 21

Microtubules: hollow tubes with walls containing 13 columns of tubulin protein Microfilaments: solid rods of two intertwined strands of actin Intermediate Filaments: hollow tubes made up of heterogeneous proteins

Question 22

What is the difference between microtubules, microfilaments, and intermediate filaments in terms of size?

Answer 22

Microtubules: 25 nm with 15 nm lumen Microfilaments: 7 nm Intermediate Filaments: 8-10 nm

Question 23

What is the difference between microtubules, microfilaments, and intermediate filaments in terms of what they are found in?

Answer 23

Microtubules: monomers, alpha-tubulin, Beta-tubulin Microfilaments: G actin and F actin Intermediate Filaments: 5 different proteins from the keratin family

Question 24

What is the difference between microtubules, microfilaments, and intermediate filaments in terms of types of cells?

Answer 24

Microtubules: present in all eukaryotic cells Microfilaments: actin in all eukaryotic cells, myosin only in animal cells Intermediate Filaments: almost in all eukaryotic cells

Question 25

What is the difference between microtubules, microfilaments, and intermediate filaments in terms of function?

Answer 25

Microtubules: 1. Cell motility (cilia, flagella, sperm) 2. Cell Shape 3. Chromosome 4. Serve as tracks for movement of organelles Microfilaments: 1. Cell Motility (amoeboid movement using pseudopodia) 2. Cell shape and change 3. Muscle contraction 4. Cytoplasmic streaming in plant cells 5. Cleavage Furrow Intermediate Filaments: 1. Structural support 2. Tensile strength 3. Cell shape 4. Anchoring the nucleus and other cell organelles 5. Formation of nuclear lamina

Question 26

Describe fungal cell walls

Answer 26

chitin in fungal cell walls can be degraded by chitinase to protect against fungal infections

Question 27

Describe bacterial cell walls

Answer 27

NAM-NAG linkage can be degraded by lysozyme to protect against bacterial infection

Question 28

Describe tight junction

Answer 28

two cell membranes are fused by integral membrane proteins to prevent movement of any solutes through the space between

Question 29

Describe gap junction

Answer 29

connections between two cells through connexons, channels through which chemical signals or solutes can pass from one cell to another; important for cell-to-cell communication

Question 30

Describe desmosomes

Answer 30

spots where two cells are connected together by keratin-like fibrous proteins; contains cytoplasmic protein plaques; not as tightly sealed as tight junctions, some space exists between two adjacent cells