Cell Bio Organelles

Question 1

What do ribosomes do?

Answer 1

site of protein synthesis
either free or attached to intracellular membranes
where proteins are made @ free and RER attached ribosomes
proteins made at RER ribos are moved into RER lumen, carbs are added -> glycoproteins
–> glycoproteins moved rto cis face of Golgi in transport vesicles that bud from ER membrane

contain RNa and protein
involved in protein synthesis
translocation process in cytoplasm; converts genetic info in RNA to proteins

Question 2

What does the endoplasmic reticulum do?

Answer 2

internal transport system
network of intracellular membranes where secreting proteins are synthesized

Rough ER: ER and ribosomes
-supply raw stuff fro protein synthesis

Smooth ER: ER without ribosomes

• functions in breakdown of fats attached to rough ER in Golgi complex
• modding of newly made polypeptide chains

Question 3

What does the mitochondria do?

Answer 3

has outer membrane + convoluted inner membrane
site of aerobic cellular respiration
site of ATP production in cell

Question 4

What do vesicles do?

Answer 4

small cell organelles in cells
membrane enclosed sacs
store and transport stuff in and between cells
has at ;east one phospholipid bilayer (like plasma membrane)
can fuse with plasma membrane when releasing contents out of cell boundaries
varies depending on type of vesicle

Question 5

What do lysosomes do?

Answer 5

recycling centre
has enzymes to digest taken in material or damaged tissues
only in animal cells
has small sacs with single layer membrane
involved in cellular digestion
eliminates bad stuff with endocytosis through phagocytosis

Question 6

What do vacuoles do?

Answer 6

mostly in plant and fungal cells
filled with fluid and enzymes in solution
isolates materials (potentially harmful to it)
contains waste products
autophagic vesicle ingests and destructs invading bacteria
stores liquids to increase cell surface area
-maintains turgor pressure in cell and pH

Question 7

What do transport vesicles do?

Answer 7

membrane bind just secreted proteins
made on ribosomes found in RER
most of the proteins age in Golgi before moving to lysosomes, peroxisomes, or out of cell in transport vesicles
move molecules between locations in cell

Question 8

What do secretory vesicles do?

Answer 8

contain to be excreted stuff
can contain waste or end products
there are diff types of secretory cells, just not listed in the packet

Question 9

What is the microbody (peroxisome)?

Answer 9

the organelle that contains specialized enzymes that oxidize molecules normally in cell
in the cytoplasm of eukaryotes
oxidizes fatty acids and amino acids
-> makes hydrogen peroxide

Question 10

What do centrioles do?

Answer 10

organize spindle fibers in cell division
composed mainly of tubulin
found in most eukaryotes
bound pair of centrioles surrounded by pericentriolar material = centrosome
produce cilia during interphase, and aster and spindle during cell division

Question 11

What is the cytoskeleton?

Answer 11

important in cell shape, internal organization, cell movement, and organelle anchoring
consists of microtubules, intermediate fibers, and microfilaments
microtubules and microfilaments frequently made and unmade for movement and maintaining cell shape
location and appearance varies
intercellular had flagella and cilia, intracellular–cytoplasmic streaming

Question 12

What are intermedit\ate filaments?

Answer 12

more permanent than microtubules and microfilaments

provide tensile strength for cell

Question 13

What are microtubules?

Answer 13

made of tubulin
act as a scaffold for cell shape
provide st of tracks for organelle and vesicle movement
form spindle fibers that separate chromosomes in mitosis
arranged n geometric patterns in flagella and cilia for locomotion

Question 14

What are microfilaments?

Answer 14

made of actin
associated with myosin (protein) to enable cell mobility, contraction, and intracellular transportation
near nucleus
helps will cell division (cytokinesis)

Question 15

What are metaphase chromosomes? Where are they?

Answer 15

coiled chromosomes during metaphase of mitosis

Question 16

What is chromatin fiber? Where is it?

Answer 16

fiber of repeating nucleosomes
coiled and condensed o form chromosomes
chromatin are made of nucleosomes and condensed chromatin fibers = chromosomes

Question 17

What is solenoid? Where are they?

Answer 17

coiling of nucleosomes like a phone cord

process of winding of DNA helix

Question 18

What are nucleosomes? Where are they?

Answer 18

fundamental repeating units of DNA wrapped around 8 histone proteins and stretches of linker DNA
the basic repeating unit of eukaryotic chromatin
scaffold for forming of higher-order chromatin structure
layer of regulatory control of gene expression

Question 19

What is the nucleus? WHat does the nucleus do?

Answer 19

the control center of cell dark-staining body in all cells
enclosed by an intracellular membrane called the nuclear envelope
used in DNA replication and transcription
contains DNA as chromatin fibers
contains RNA (mRNA, rRNA, tRNA)
nuclear membrane/envelope has pores filled with ring of proteins (annulus)

Question 20

What are the organelles specific to plant cells?

Answer 20

chloroplast - involved in photosynthesis
central vacuole - provides support to plant via osmotic pressure
cell wall - made of cellulose, provides extra strength and rigidity

Question 21

What are chloroplast? What do they do?

Answer 21

store chlorophyll - absorb light energy
used in photosynthesis (light reaction)
green plastic
gets color from chlorophyll a and b in thylakoids of chloroplasts
also have carotenoids that capture energy
concentrated in parenchyma cell of mesophyll
encased in the chloroplast envelope
== inner - intermembrane - outer
the innermost membrane is the thylakoid membrane
right wavelengths excite e- of chlorophyll, energy is then transferred to an acceptor moelcule

Question 22

what is the golgi apparatus? What does it do?

Answer 22

packing center
membranous organelle
packs and sorts newly made secretory proteins
final modification fo protein and lipids before secretion

Question 23

What is cytoplasm? What does it do?

Answer 23

= most of the protoplasmic substance in a cell
the membrane between plasma membrane and nucleus and many organelles
includes cytosol (fluid of cytoplasm)
outside organelles
has water, free proteins, and other stuff
part of where cellular metabolism happens
proteins included are important in glycolysis (and intracellular receptors and part of ribosomes, enables protein synthesis)
has cytoskeleton
endomembrane system: has nuclear envelope, ER, Golgi, vesicles, and other derived from them
sorts stuff

Question 24

Describe the surface of a cell

Answer 24

Cell wall - common in plant cells, provides protection and support
Plasma membrane - controls substances (in and out)
Cilia - sweeps stuff across the cells surface
Flagellum - propels cell in different directions

Question 25

Describe eukaryotic cells

Answer 25

eu = true karyon = nucleus
has a complex membrane system
has true nucles
membrane-bound intracellular compartments

Question 26

Describe prokaryotic cells

Answer 26

small and primitive bacteria and blue-green algae
don’t have specialized membrane-bound organelles

Includes:
cell membrane - transports substances and produces energy
cell wall - structural strenght
capsule - jelly-like and protects cell wall
nucleoid - has single circular DNA molecule
cytoplasm - surrounds nucleoid in the cell membrane and has ribosomes and RNA
vacuole (vesicles) - site of photosynthesis and used for storage
flagellum - protein fiber and used for movement

Question 27

Compare and contrast prokaryotic and eukaryotic cells

Answer 27

Prokaryotic:
single-celled
most often with a cell wall
no membrane-bound organelles

Eukaryotic:
a membraned nucleus around genetic material
other membraned organelles

Question 28

What is cell theory?

Answer 28

all living organisms made of cells
cells are functional units of living organisms
arise from preexisting cells through division

Question 29

Define a cell

Answer 29

a fundamental structural and functional unit of all organisms
highly organized molecular and biochemical systems
store information
use energy
can move
sense environmental changes
can duplicate
can self regulate
microscopic

Question 30

Name the structures of a eukaryotic cell (use diagram)

Question 31

Name the structures of a prokaryotic cell (use diagram)

Question 32

Name the structures of a nucleus (use diagram)

Question 33

Identify the chromatin fiber, solenoid, metaphase chromosomes, and nucleosomes (use diagram)

Question 34

Compare and contrast prokaryotic and eukaryotic cells

Answer 34

Prokaryotic:
unicellular
sticky capsule
all bacteria
have ribosomes
no true nucleus
no membrane bound organelles 
single chromosome
no streaming in the cytoplasm
cell division without mitosis
simple flagella
smaller ribosomes
simple cytoskeleton
no cellulose in cell walls
no histone proteins

Eukaryotic:
true nucleus
can be unicellular or multicellular
have cytoskeleton
some have cilia
includes everything but bacteria
membrane-enclosed organelles
chromosomes in pairs
streaming in cytoplasm
cell division by mitosis
complex flagella
larger ribosomes
complex cytoskeleton
cellulose in cell walls
DNA bound to histone proteins