Chapter 2- The structure of cells

Question 1

Definition: Centrioles

Answer 1

Pair of cylindrical structures composed of microtubules that are involved in the separation of chromosomes during cell division in animals and protists.

Question 2

Definition: Chloroplast:

Answer 2

A green organelle composed of many layers of folded membrane, found in some animal cells in which photosynthesis takes place.

Question 3

Definition: Cytoplasm

Answer 3

The contents of a cell, other than the nucleus. (More than 90% water and contains salts, ions, enzymes, food molecules).

Question 4

Definition Cytosol

Answer 4

The fluid part of a cell, in which organelles are located.

Question 5

Definition: Endoplastic reticulum:

Answer 5

Network of intracellular membranes that is involved in the production, processing, transport and storage of materials within the cell.

Question 6

Definition: Golgi apparatus:

Answer 6

A stack of flat membrane sacs where the final synthesis and packaging of proteins into membrane- bound vesicles occurs before they are secreted from the cell. (Linked to E.R.)

Question 7

Definition: Lysosomes:

Answer 7

Membrane bound vesicles containing powerful enzymes that break down foreign debris and material in animal cells.

Question 8

Definition: Mitochondria:

Answer 8

Organells composed of many folded layers of membrane, produces energy via aerobic respiration.

Question 9

Definition: Nucleus:

Answer 9

Large organelle that is surround by a double- layered nuclear membrane. It contains genetic material and controls cellular activities.

Question 10

Definition: Plasma membrane:

Answer 10

Layer of molecules enclosing the cytoplasm and controls what substances enter and leave the cell.

Question 11

Definition: Pastids

Answer 11

Group of organelles, found only in plant cells, which develop from simple organelles called proplasts

Question 12

Definition: Ribosomes

Answer 12

Tiny organelles located in the cytosol that are sometimes associated with the E.R. They are the site of the production of protein.

Question 13

Definition: Tonoplast

Answer 13

The vacuole membrane in plants cells that regulates the substances into and out of the vacuole.

Question 14

Definition: Vacuole

Answer 14

Membrane bound, liquid filled space.

Question 15

Definition Vesicles

Answer 15

Membrane- bound organelle involed with transport in cells.

Question 16

What are the three common features of cells

Answer 16

1) Cytoplasm
2) Cell membrane
3) DNA/ genetic material

Question 17

Definition: Nucleoid

Answer 17

Region where DNA is contained in prokaryotes.

Question 18

Definition: Plasmids

Answer 18

Rings of double stranded DNA

Question 19

Definition: Microtubules

Answer 19

hollow tubes found in cytoplasm of all eukaryotic cells that shape and support the cell.

Question 20

Definition: Protist

Answer 20

large diverse groups of eukaryotic micro-organisms, which belong to the kingdom Protista.

Question 21

Definition: Hetereotroph

Answer 21

Organism that must obtain organic compounds by eating other organisms or their products.

Question 22

What are the five kingdoms of cells?

Answer 22

Monera, Protista, Fungi, Plantae, Animalia

Question 23

Definition: Microfilaments

Answer 23

Long, thin protein polymers

Question 24

Definition: Autotrophic

Answer 24

Organisms that manufacture their own organic material

Question 25

Definition: Prokaryotes

Answer 25

Cells that lack a nucleus and membrane- bound organelles.

Question 26

Deinition: Eukaryotes

Answer 26

Cells that contain a nucleus and membrane- bound organelles.

Question 27

What are Protists? Give an example.

Answer 27

Any organism that is not a plant, animal or fungi. | E.g. flagella

Question 28

What are fungi? Give examples.

Answer 28

Heterotrophs that feed by absorption (can become thousands of acres big and can live in a variety of environments) Eg. mould, mushroom, yeast

Question 29

What are Plantae? Give examples.

Answer 29

Plants, multicellular with cell walls made of cellulose), feeds by means of photosynthesis E.g. ferns, mosses, conifers

Question 30

What are Animalia? Give examples.

Answer 30

Multicellular heterotrophic, digests food in an internal chamber and does not have cell walls. E.g. crustaceans, insects, mollusks, centipedes.

Question 31

Name some current microscopy techniques.

Answer 31

``` Light microscopy (including autoradiography, fluorescence and confocal microscopy) Synchrotron light ```

Question 32

What does confocal microscopy examine?

Answer 32

Very thin sections through living tissue

Question 33

What is a synchrotron and what does synchrotron light do?

Answer 33

Synchrotron- large circular tube inside which electrons are travelling at close to the speed of light. Synchrotron light- allows matter to be 'seen' at the atomic scale including changing in structure of protein molecules.

Question 34

What does light microscopy use light to examine?

Answer 34

Uses visible light to examine cells and tissues.

Question 35

What does electron microscopy use instead of light to view an object and what does it allow?

Answer 35

Viewed using an electron beam instead of light because it allows a much higher resolution.