Cell Structures and Functions

Question 1

What does a typical structure of a bacteria (prokaryotic)?

Answer 1

plasma membrane, cell wall, capsules and slime layers, flagellum, fimbriae, pili, nucleoid, endospore

Question 2

What does the plasma membrane consist of?

Answer 2

phospholipids and proteins

Question 3

Does all prokaryotes have a cell wall and what does it do?

Answer 3

yes, support, protection and shape

Question 4

What does bacteria have in their cell walls?

Answer 4

peptidoglycan

Question 5

What are capsules and slime layers and what do they do?

Answer 5

sticky layer of polysaccharides or protein surrounding the cell wall (sticking, and prevents dehydration)

Question 6

What is the flagellum used for?

Answer 6

movement

Question 7

What are fimbriae?

Answer 7

hair like projections that help stick to things

Question 8

What are pili?

Answer 8

long projections to trainer DNA between cells

Question 9

Where is the nucleoid?

Answer 9

in the cytoplasm where the chromosome is

Question 10

What is the plasmid?

Answer 10

unique to some bacteria where there is DNA separate from main chromosome

Question 11

What is the endospore and why does it form?

Answer 11

copy of chromosome surrounded by multilayer cell wall; formed for survival in harsh conditions

Question 12

Is there a presence of a nuclear envelope in bacteria, archaea, eukarya?

Answer 12

bacteria - no
archaea - no
eukarya - yes

Question 13

Is there a presence of membrane bound organelles in bacteria, archaea, eukarya?

Answer 13

bacteria -no
archaea - no
eukarya - yes

Question 14

What are the types of membrane lipids in bacteria, archaea, eukarya?

Answer 14

bacteria - unbranched hydrocarbons
archaea - some branched hydrocarbons
eukarya - unbranched hydrocarbons

Question 15

Is there a presence of circular chromosome in bacteria, archaea, eukarya?

Answer 15

bacteria - yes
archaea - yes
eukarya - no

Question 16

What are the key structure of the endomembrane system?

Answer 16

nuclear envelope/nucleus
ER
golgi apparatus
lysosomes
vacuoles
plasma membrane

Question 17

What are the components of the nuclear envelope/nucleus?

Answer 17

envelope - inner and outer membrane
pore - material entry/exit
chromatin - DNA + protein
nucleolus - site of rRNA synthesis
lamins - A+B give structural support to nucleus

Question 18

What are lysosomes?

Answer 18

membrane bound organelles packed with enzymes (recycling center)
acidic
proton pump
enzymes - hydrolysis of covalent bonds - complex molecules - simpler forms

Question 19

What is the ER and what is the difference between smooth and rough?

Answer 19

protein traffic, 1 membrane
rough - attached ribosomes, help fold and traffic proteins
smooth - no attached ribosomes, makes lipids, detoxify and metabolize

Question 20

What are the 3 types of vacuoles and their functions?

Answer 20

food - engulf food or particles
central - plants; site of storage with tonoplast membrane
contractile - single cell - pump out water

Question 21

What is the function of the golgi apparatus?

Answer 21

modification, packaging, and protein transport
cis face - trans face

Question 22

what is the function of the plasma membrane?

Answer 22

cell protection
encloses cell
bounds the cytoplasm inside of a cell

Question 23

what are peroxisomes?

Answer 23

single membraned organelles that uses O2 to create hydrogen peroxide using the hydrogen atoms from organic compounds; the peroxide can then be broken down into water and oxygen; found in liver

Question 24

What is the mitochondria and chloroplasts?

Answer 24

mito. - double membraned organelle involved in the site of cellular respiration
chloroplast - plant organelle containing an inner/outer membrane, photosynthesis

Question 25

What is the components/function of the extracellular matrix (ECM)?

Answer 25

structure surrounding animal cells
comprised of proteins
bind to membrane proteins called integrins
changes can cause inner cell changes

Question 26

What are the 3 components of the cytoskeleton?

Answer 26

microtubules, microfilaments, intermediate filaments

Question 27

what are microtubules made of/function and examples?

Answer 27

alpha and beta tubulin (tubulin dimer)
maintain cell shape, cell motility, chromosome movements in cell division, and organelle movements
ex. vesicles walking on microtubules, centrosomes and centrioles, cilia and flagella

Question 28

what are microfilaments made of/function and examples?

Answer 28

actin
maintain cell shape, changes in cell shape, muscle contraction, cytoplasmic streaming, cell motility, and cell division
ex. actin-myosin interactions, ameboid movement, cytoplasmic streaming

Question 29

what are intermediate filaments made of/function.

Answer 29

proteins of the keratin family
maintain cell shape, anchorage of nucleus and certain other organelles, and formation of nuclear lamina

Question 30

What are the cell junctions of animal cells and what do they allow pass?

Answer 30

tight - nothing can pass between the cells
desmosomes - some things can pass between the cells
gap - everything can pass between the cells

Question 31

what are the cell junctions of plant cells and what do they allow pass?

Answer 31

plasmodesmata - channels between plant cells that allow water and nutrients to pass between cells; similar to gap junctions