Vce Biology: Cells And The Membrane

Front 1

What is a gene?

Back 1

A segment of DNA that determines the structure of one protein.

Front 2

What is a virus?

Back 2

They are not cells. They are non-living infectious agents that share some characteristics with living things.

Front 3

What does a virus consist of?

Back 3

They consist of a nucleic acid core (DNA or RNA) with a coat of protein, known as a capsid. Some viruses are also enveloped in a modified membrane from a host cell.

Front 4

How does a virus reproduce?

Back 4

They are inert outside of a host cell. Inside a host cell however, the nucleic acid of a virus is activated. Viruses reproduce inside the cells of other organisms, using the host cell's energy sources and raw materials to produce more viruses. Ultimately the host cell dies, releasing more viruses to infect other cells.

Front 5

Define prokaryotic cells:

Back 5

Are the smallest of living cells, they lack membrane bound organelles.

Front 6

Give an example of a prokaryote:

Back 6

Bacteria, archaebacteria and eubacteria.

Front 7

How do prokaryotes reproduce?

Back 7

Through binary fission which is a-sexual. They reproduce like in mitosis where two daughter cells are the result.

Front 8

Define eukaryote:

Back 8

A cell or or organism with membrane bound organelles.

Front 9

What is an organelle?

Back 9

Structures within a cell that carry out a specific purpose.

Front 10

What are examples of organelles?

Back 10

Smooth ER, mitochondrion, lysosome, golgi body, ribosome, nucleus etc.

Front 11

What is the cell membrane?

Back 11

It is a double layer of phospholipids embedded with protein molecules, glycoproteins and some short carbohydrate chains. It encloses the cell's contents and regulates the movement of materials into and out of the cell. It helps to maintain the cell's shape and communicates with neighbouring cells.

Front 12

What is the nucleus?

Back 12

It is surrounded by a double membrane and is usually large compared to other organelles. It contains chromosome which control the production of proteins in the cell. These proteins, in turn, control cellular function.

Front 13

What is the nuclear membrane?

Back 13

It is a double membrane, containing many prores, which separate the nucleoplasm from the rest of the cell. It regulates the movement of material between the cytoplasm and the nucleus.

Front 14

What is the nucleolus?

Back 14

It is a granular structure in the nucleus, made of protein and nucleic acid. It is the site of ribosomal RNA production.

Front 15

What are the mitochondria?

Back 15

They are sacs made up of two membranes. The inner membrane is folded to create cristae, which increase the surface area. The cristae enclose the fluid-filled matrix. It is the site of aerobic cellular respiration, they are responsible for most of the cell's energy production.

Front 16

What are ribosomes?

Back 16

They are small spherical bodies composed of RNA and protein. They are the site of protein synthesis.

Front 17

What is smooth endoplasmic reticulum?

Back 17

It is a network of membranes that create channels in the cytoplasm from the nucleus to the cell membrane. It is the site of lipid synthesis and transport of many materials throughout the cell.

Front 18

What is rough endoplasmic reticulum?

Back 18

A network of membranes that create channels in the cytoplasm. Rough ER is studded with ribosomes. It is responsible for the transport and folding of proteins produced by ribosomes. It is responsible for the synthesis of glycoproteins.

Front 19

What is the golgi complex/body/apparatus?

Back 19

It is comprised of stacks of flattened membrane sacs. It packages proteins and glycoproteins into vesicles for secretion from the cell or to be sent to other organelles. It modifies some proteins and glycoproteins. It also synthesises cellulose in plant cells.

Front 20

What is a lysosome?

Back 20

It is an organelle only present in animals. It contains many digestive enzymes that digest ingested materials and wastes. It is important for programmed cell death.

Front 21

What is a vacuole?

Back 21

A membrane-bound sac containing fluid, sugars and ions. It is important in turgor in plant cells; the pressure of fluid in the large vacuole helps maintain cell shape. It is also used for storage of sugars, ions and food.

Front 22

What is a chloroplast?

Back 22

Surrounded by a double membrane, it contains stacks of membranes (grana) embedded in a less-dense membrane and fluid (stroma). It is the site of photosynthesis; grana (or thylakoid membranes) contain chlorophyll, the pigment that traps light energy.

Front 23

What is the cell wall?

Back 23

It is a layer of cellulose in plants secreted by the cell and completely surrounds the cell membrane. It provides structural support and defines the shape of cells.

Front 24

What is cell specialisation?

Back 24

Variations in cell structure that are related to function. Cells vary in the number of each organelle present, and in their shape and life cycle.

Front 25

What cells are specified for the absorption of materials?

Back 25

A cell lining the intestine or a root hair cell.

Front 26

What are cells specialized for photosynthesis?

Back 26

A leaf cell or stem (plant) cell.

Front 27

What cells are specialized for communication?

Back 27

A motor neuron, a sensory neuron or a interneuron.

Front 28

What cells are specialized for transport?

Back 28

A sieve tube cell.

Front 29

Does the cell's surface area increase or decrease if a cell grows in size/volume?

Back 29

It decreases.