Download 4.3- 4.4 organelles answers.docx

4.3 - 4.4 Organelles Answers
Cell Membrane
1.
plasma membrane or phospholipid bilayer
2.
gateway of the cell - controls what enters/exits the cell thus helping to maintain cell
homeostasis
3.
permeable = things can pass through; selective = only certain things; so the cell membrane
only lets certain things pass easily in/out
4.
mosaic refers to all the pieces that make up the membrane (phospholipids, proteins, carbs,
steroids); fluid means all of those pieces are moving around - they are not still; so the
membrane is more like a liquid than a solid
5.
phospholipids, carbohydrates, steroids, and proteins
6.
phospholipids
7.
steroids - cholesterol specifically - provides strength
8.
carbs - help cells stick together, serve as recognition sites on cells
9.
peripheral proteins = attached to inner or outer surface of membrane, used in recognition
of materials; integral = extend through both layers of the cell membrane; transport
materials into and out of the cell
Cytoplasm and Cytosol
10.
cytoplasm = region of the cell between the nuclear membrane and the cell membrane;
contains fluid, cytoskeleton and all organelles except nucleus
11.
cytosol = part of cytoplasm that includes fluid and molecules and small particles dissolved in
fluid
Nucleus
12.
control center of the cell; houses the DNA; site of transcription (copying) of RNA (DNA →
RNA)
13.
- nuclear matrix = protein skeleton, helps maintain shape of nucleus
- nuclear envelope (membrane) = double lipid bilayer, controls what enters/exits the
nucleus
- nuclear pores = small holes in the nuclear membrane where RNA and ribosomal subunits
pass from the nucleus to the cytosol
- nucleolus = inside nucleus, where ribosomes are made
14.
chromatin = long, drawn out DNA, how DNA exists in a nondividing cell, DNA exists as
chromatin most of the time; chromosomes = coiled up, condensed form of DNA, exist during
cell division
Ribosomes
15.
most numerous structure in cells; NOT membrane-bound, made of 2 subunits of RNA and
proteins
16.
dehydration synthesis of proteins a.k.a., protein synthesis; this is where amino acids link
together to form the primary structure of a protein
17.
free ribosomes - float in the cytoplasm, proteins made on these ribosomes STAY in the cell;
bound ribosomes - attached to ER making it rough ER, proteins made on bound ribosomes will
EXIT the cell
Endoplasmic Reticulum
18.
membrane system of folded sacs (called cisternae) inside the cell; largest internal
membrane in the cell; continuous with nuclear membrane
19.
intracellular highway - molecules move around the cell through the ER (like hallways in the
school)
20.
rough ER - has ribosomes attached to the surface so it looks pebbly; smooth ER - no
ribosomes on surface, additional functions include: stores/regulates protein levels,
detoxification of drugs/alcohol, synthesis of lipids
Golgi Complex
21.
stacks of flattened membranous sacs with a receiving end where vesicles fuse with it and a
discharging end where vesicles bud from it
22.
processing, packaging and secreting organelle; modifies proteins into functional structure
23.
release or give off
24.
proteins leaving the cell are made on bound ribosomes of RER → protein moves into and
travels through ER → protein packaged into vesicle → vesicle moves to and fuses with Golgi
releasing protein into Golgi → protein moves through Golgi where it’s modified → protein is
packaged in new vesicle → vesicle is released from Golgi and travels toward cell membrane
→ vesicle fuses with cell membrane releasing contents to outside of cell (this step is called
exocytosis)
Mitochondria
25.
site of cellular respiration or conversion of glucose into ATP for energy for the cell
26.
bean shaped outer membrane, folded inner membrane
27.
cristae
28.
folds increase surface area allowing more area for chemical reactions of cellular respiration
to occur
29.
very active cells, like muscle cells, have a lot of mitochondria because these cells have high
energy requirements and need more ATP unlike less active cells which have lower energy
requirements, need less ATP, and therefore have less mitochondria
Vesicle
30.
lipid bilayer “bubbles” inside of the cell that are classified by their contents
31.
contain digestive enzymes and can digest all organic molecules, food particles,
microorganisms, damaged cell parts or even the cell itself
Cytoskeleton
32.
protein strands that are connected to inner surface of cell membrane and span the
cytoplasm
33.
NO
34.
swirling movement of the cytoplasm around the inside of the cell caused by microfilaments
35.
maintain cell shape, help make cell resistant to damage, aids in moving organelles around
36.
microtubules, intermediate filaments, and microfilaments
37.
a. microfilaments
b. microtubules
c. intermediate filaments
d. microtubules
e. microfilaments
f. microfilaments
Cilia and Flagella
38.
microtubules
39.
internal arrangement of the microtubules of both cilia and flagella; internally these
structures are made up of 9 pairs of microtubules in a circle + 2 in the middle
40.
basal bodies
41.
9 by 3 - 9 triplets of microtubules in a circle (no central pair)
42.
cilia - short, hair-like, numerous; flagella - long, tail-like, usually one or a few
43.
movement of the cell itself - allows cells to swim; cilia can be used on stationary cells to
move substances across the surface of the cell
Centrioles
44.
microtubules
45.
found in a pair, located next to the nucleus of a nondividing cell; animal cells only
46.
organize microtubules called spindle fibers that move organelles during cell division
Plant Cells
47.
cell wall, plastids, central vacuole
Cell Wall
48.
outer-most layer of a plant cell; gives plant cells strength and support
49.
cellulose
50.
primary - in young cells, elastic and has give to allow cells to grow; secondary - in mature
cells, secreted when cells stop growing, very rigid and tough
51.
lignin
52.
gluey substance between primary cell walls of adjacent plant cells so the cells can stick
together; made of pectin
Central Vacuole
53.
stores large amounts of water but can also store organic molecules, toxins, and waste
products
54.
the vacuole is the largest structure in plant cells and takes up a majority of the cytoplasm
Plastids
55.
chloroplasts, chromoplasts, leucoplasts
56.
contain chlorophyll which is a green pigment
57.
site of photosynthesis (where light energy from the sun is converted into chemical energy in
the form of glucose)
58.
thylakoids
59.
chromoplasts
60.
leucoplasts