Bio 210 Exam 2 - Structure Vs Function Organelles

Front 1

Ribosome

Back 1

Structure:

Composed of 2 subunits, one large, one small

Each subunit is an aggregation of proteins and rRNA

Hint 1

Function:

Site of protein synthesis

Front 2

Endoplasmic reticulum

Back 2

An extensive membranous network in eukaryotic cells, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free (smooth) regions.

Front 3

Rough
endoplasmic reticulum (RER)

Back 3

Structure:

Network of membranous sacs called cisternae; ribosomes attached to the cytoplasmic surface of the membranes

Hint 3

Function:

Synthesis of proteins that are secreted from the cell

Membrane factory

Front 4

Smooth
endoplasmic reticulum (SER)

Back 4

Structure:

Network of membranous tubules

Membrane lack ribosomes

Hint 4

Function:

Synthesis of lipids, such as oils, phospholipids and steroids

Carbohydrate metabolism

Detoxification of drugs

Front 5

Golgi apparatus

Back 5

Structure:

Stack of flattened membranous sacs (cisternae)

Has distinct polarity with receiving and shipping ends

Hint 5

Function: Products of the ER are modified, stored, and packaged for other destinations.
Manufactures some polysaccharides and attaches them to a protein synthesized from ER to form proteoglycans

Important in the processing of proteins for secretion.

Front 6

Lysosome

Back 6

Structure:

Membrane-enclosed sac of hydrolytic (digestive) enzymes

Internal pH of 5

Hint 6

Function:

Digest macromolecules used for food or help defend the body by digesting potentially dangerous bacteria

Recycle cell’s own organic material

Front 7

Plant vacuole

Back 7

Structure:

Enclosed by a membrane called the tonoplast

Sac containing mostly water and some dissolved materials

Hint 7

Function:

Stores organic compounds and
inorganic ions.
Disposal site for metabolic by-products.

May contain pigments
May contain toxins

Role in growth of plant cells

Front 8

Peroxisome and glyoxysome

AKA: Microbodies

Back 8

Single-membrane-bound spherical sac with no internal structure

May contain a large crystal

Hint 8

Function:
Both produce and destroy H2O2

Peroxisome:
Breaks down fatty acids into smaller molecules that are used as fuel for cellular respiration; detoxifies drugs and alcohol

In animal cells, helps degrade purines/detoxify drugs.

Glyoxysomes:
Converts fatty acids to sugars (in seeds)

Front 9

Mitochondrion

Back 9

Structure:

Enclosed by 2 membranes:

Outer membrane smooth, inner membrane folded into cristae

Inner membrane encloses the matrix that contains ribosomes and DNA

Hint 9

Function:

Site of cellular respiration

Front 10

Chloroplast

Back 10

Structure:

Enclosed by 2 membranes
Third membrane system of flattened sacs called thylakoids stacked in grana.

Fluid surrounding grana called stroma which contains ribosomes and DNA.

Grana and thylakoids contain chlorophyll

Hint 10

Site of photosynthesis

Front 11

Nucleus

Back 11

Structure:

Enclosed by 2 membranes called the nuclear envelope
Pores in the nuclear envelope

Contains DNA in chromosomes

Contains the nucleolus

Hint 11

Function:

Stores genetics information

Controls protein synthesis, which occurs in the cytoplasm

Front 12

Nucleolus

Back 12

Structure:

Roughly spherical

Mass of densely stained granules and fibers adjoining parts of the chromatin

Hint 12

Function:

Synthesis of rRNA

rRNA and proteins assembled into ribosomal subunits (large and small)

Front 13

Microtubules

Back 13

Structure:

Hollow tubes composed of the protein tubulin

Approximately 25 nm in diameter

Hint 13

Function:

Maintenance of cell shape (cytoskeleton).
Cell motility (major component of
cilia and flagella).
Chromosome movement in cell division.
Organelle movements.

Front 14

Microfilaments

Back 14

Structure:

2 intertwined strands of the protein actin

Approximately 7 nm in diameter

Hint 14

Function:

Maintenance of cell shape (cytoskeleton).
Changes in cell shape.
Muscle contraction.
Cytoplasmic streaming (cyclosis).
Cell motility (amoeboid movement).
Formation of cleavage furrow during cell division.

Front 15

Intermediate filaments

Back 15

Structure:

Fibrous proteins (such as keratin) supercoiled into cables

8-12 nm in diameter

Hint 15

Structure: Fibrous proteins (such as keratin) supercoiled into cables

Function:

Maintenance of cell shape (cytoskeleton). Anchorage of nucleus and other organelles. Nuclear lamin type forms meshwork that stabilizes inner membrane of nuclear envelope

Front 16

Eukaryotic
cilia and flagella

Back 16

Structure:

Contain a core of 9 doublets of
microtubules in a ring.

Contain other proteins in the radial spokes, arms coming off of the doublets, and other structures

Hint 16

Function:

Propels single cells through liquid.

Cilia: May propel fluid over the
surface of eukaryotic cells fixed in place in a tissue.

Front 17

Centrioles and basal bodies

Back 17

Structure:

Composed of 9 sets of triple microtubules arranged in a ring.

Structurally identical to each other.

Hint 17

Function:

Centriole: May help organize microtubule assembly when cell divides.

Basal body: Anchors cilium or flagellum to the cell.

Front 18

Bacterial flagella

Back 18

Structure:

Composed of protein flagellin + other proteins.

Filament, hook, basal apparatus

Hint 18

Function:

Propels cell through liquid

Front 19

Plant cell wall

Back 19

Structure:

Composed mainly of cellulose embedded in a matrix of other polysaccharides and protein.

Primary: All plant cells; relatively thin and flexible.

Secondary: Some cells; between plasma membrane and primary wall; strong and durable.

Hint 19

Function:

Protects the plant cell

Maintains cell shape

Prevents excessive uptake of water.

Front 20

Bacterial cell wall

Back 20

Structure:

Composed of peptidoglycan (i.e. a polymer of modified sugars crosslinked by short polypeptides).

Hint 20

Function:

Protects the cell.

Maintains cell shape.

Prevents excessive uptake of water.

Front 21

Microvilli

Back 21

Structure:

Cylindrical projection. Long and skinny. High SA/V ratio

Hint 21

Functions:

Increase the cell's surface area

Front 22

Nuclear Envelope

Back 22

Structure:

In a eukaryotic cell, the double membrane that surrounds the nucleus, perforated with pores. The outer membrane is continuous with the endoplasmic reticulum.

Hint 22

Function:

Regulates traffic with the cytoplasm.

Front 23

Chromatin

Back 23

Structure:

When the cell is not dividing, this exists in its dispersed form, as a mass of very long, thin fibers that are not visible with a light microscope.

Hint 23

Function:
The complex of DNA and proteins that makes up eukaryotic chromosomes.

Front 24

Plasmodesmata

Back 24

Structure:
An open channel through the cell wall that connects the cytoplasm of adjacent plant cells, allowing water, small solutes, and some larger molecules to pass between the cells.

Front 25

Central Vacuole

Back 25

Structure:

In a mature plant cell, a large membranous sac with diverse roles in growth, storage, and sequestration of toxic substances.

Front 26

Plastids

Back 26

One of a family of closely related organelles that includes chloroplasts, chromoplasts, and amyloplasts.

Are found in cells of photosynthetic eukaryotes.

Front 27

Animal vs plant cells

(what is difference in organelle composition?)

Back 27

Only animal cells normally have:

Centrioles
Lysosomes
Cilia

Hint 27

Only plant cells normally have:

Central vacuole
Plastids
Cell wall
Chloroplasts