Unit 1-Area Of Study 1-Cells

Question 1

Cells

Answer 1

Basic structural and functional unit of life(all living things).

Question 2

Biogenesis

Answer 2

New cells are produced from existing cells.

Question 3

Unicellular Organisms

Answer 3

Consist of one cell, e.g. bacteria , yeasts and protists. They are self contained, can be highly complex and carry out all the functions necessary for living.

Question 4

Multicellular Organisms

Answer 4

Consists of many cells e.g. plants animals and most fungi. Additional levels of organisation are required where cells perform specific functions.

Question 5

Extremophiles

Answer 5

Microbes that live in extreme
environmental conditions, such as high temperature and low pH

Question 6

Bacteria

Answer 6

Singular = (bacterium) microscopic, usually unicellular organism, and member of Kingdom Monera

Question 7

Archaea

Answer 7

One of the three domains in the Woese system of classification that includes those prokaryotic organisms known as archaeans

Question 8

Surface Area To Volume Ratio

Answer 8

Measure that identifies the number of units of surface area available to ‘serve’ each unit of internal volume of a cell, tissues or organism

Question 9

Prokaryotes

Answer 9

Any cells or organisms without a membrane-bound nucleus

Question 10

Nuclear Envelope

Answer 10

Membrane surrounding the nucleus of a eukaryote cell

Question 11

Eukaryotes

Answer 11

Cell or organism with a membrane-bound
nucleus

Question 12

Eukaryotic

Answer 12

Describing cells that have a membrane-
bound nucleus

Question 13

Plasma Membrame

Answer 13

Partially permeable boundary of a cell separating it from its physical surroundings; boundary controlling entry to and exit of substances from a cell

Question 14

Cell Membrame

Answer 14

The semipermeable Membrame enclosing the cytoplasm of a cell

Question 15

Selectively Permeable(Semipermeable)

Answer 15

Allows some
substances to cross but precludes the passage of others

Question 16

Phospholipids

Answer 16

Major type of lipid found in plasma membranes

Question 17

Proteins

Answer 17

Macromolecules built of amino acid sub- units and linked by peptide bonds to form a chain, sometimes termed a polypeptide; usual product of gene translation; some proteins consist of a single polypeptide while other proteins consist of two or more polypeptides

Question 18

Hydrophillic

Answer 18

Refers to substances that dissolve easily in water; also called polar

Question 19

Hydrophobic

Answer 19

Refers to substances that tend to be insoluble in water; also called non-polar

Question 20

Integral Proteins

Answer 20

Fundamental components of the plasma membrane that are embedded in the phospholipid bilayer

Question 21

Trans Membrame

Answer 21

A type of membrane protein spanning the entirety of the biological membrane to which it is permanently attached. That is, transmembrane proteins span from one side of a membrane through to the other side of the membrane

Question 22

Peripheral Proteins

Answer 22

Are either anchored to the exterior of the plasma membrane through bonding with lipids or are indirectly associated with the plasma membrane through interactions with integral proteins in the membrane.

Question 23

Fluid Mosaic Model

Answer 23

A model which proposes that the plasma membrane and other intracellular membranes should be considered as two- dimensional fluids in which proteins are embedded

Question 24

Receptors

Answer 24

Chemical structures, often on the surface of
cells, that receive signals from hormones, neurons
or cytokines

Question 25

Simple Diffusion

Answer 25

The movement of substances across
the phospholipid bilayer from a region of higher concentration to one of lower concentration of that substance; that is, down its concentration gradient

Question 26

Osmosis

Answer 26

Net movement of water across a partially permeable membrane without an input of energy and down a concentration gradient

Question 27

Facilitated Diffusion

Answer 27

Form of diffusion involving a specific carrier molecule for the substance that diffuses

Question 28

Active Transport

Answer 28

Movement of dissolved substance across a plasma membrane in an energy-requiring process that results in a net movement of that substance against a concentration gradient from a region of lower concentration to a region of higher concentration

Question 29

Endocytosis

Answer 29

Bulk movement of solids or liquids into a
cell by engulfment

Question 30

Hypotonic

Answer 30

Having a lower concentration of dissolved substances than the solution to which it is compared

Question 31

Isotonic

Answer 31

Having the same concentration of dissolved substances as the solution to which it is compared

Question 32

Hypertonic

Answer 32

Having a higher concentration of dissolved substances than the solution to which it is compared

Question 33

Carrier Protein

Answer 33

Protein that binds to specific
substance and facilitates its movement; may be carrier for lipophilic hormone for transport in the blood; also refers to proteins that facilitate movement across the plasma membrane

Question 34

Channel Protein

Answer 34

A protein responsible for mediating the passive transport of molecules from one side of the lipid bilayer to the other

Question 35

Pumps

Answer 35

Special transport proteins embedded across the plasma membrane that carry out the process of active transport

Question 36

Sodium Potassium Pump

Answer 36

Protein that transports sodium and potassium ions against their concentration gradients to maintain the differences in their concentrations inside and outside cells

Question 37

Lysosome

Answer 37

A sac which destroys bacteria

Question 38

Vesicles

Answer 38

Membrane-bound sac found within a cell, typically fluid-filled; for example, lysosome

Question 39

Pinocytosis

Answer 39

The ingestion of liquid into a cell by the budding of small vesicles from the cell membrane.