Introduction to Cell

Question 1

What are the levels of organisation?

Answer 1

Chemical
Cellular
Tissue
Organ
System
Organism

Question 2

What is a cell

Answer 2

• Basic structural and functional unit of an organism that is composed of chemicals
• facilitates functions, adapts (reproduction, movement, transport, protection

Question 3

What is ATP?

Answer 3

Adenosine triphosphate.
(The energy of our body, energy required to function. Gotten from glucose)

Question 4

How does a eukaryotic cell differ from a prokaryotic cell?

Answer 4

Eukaryotic - organelles, advanced, complex (fungi, plant and humans cells)
Prokaryotic - no nucleus, genetic material, unicellular organism (bacteria)

Question 5

What is the plasma membrane?

Answer 5

• Forms cells flexible outer surface, separates cells internal/external
• Made of lipids, not soluble
• Selective barrier, regulates input/output, maintains environment
• Communication among cells

Question 6

What is the cytoplasm?

Answer 6

• Consists of all cellular contents between plasma membrane and nucleus
• Cytosol and organelles

Question 7

What is the cytosol?

Answer 7

• Intracellular fluid, 55% total cell volume
• 75-90% water, suspended components - ions, glucose, amino acids, fatty acids, proteins, lipids, ATP, waste
• site of chemical reactions required for cell’s existence

Question 8

What is an organelle?

Answer 8

-Specialised structures within the cytosol
-Each type has characteristic shape and function in cellular growth, maintenance and reproduction
-Each has own set of enzymes that carry out specific reactions/functional compartment for specific biochemical processes
-Cooperating to maintain homeostasis

Question 9

What is cytoskeleton?

Answer 9

• Network of proteins filaments that extend throughout cytosol

Question 11

What does the centrosome do?

Answer 11

Creates pull within cell so it can be divided

Question 12

What are the cilia and flagella?

Answer 12

Cilia - moves fluids over cell’s surface
Flagella - moves entire cell

Question 13

What is the ribosome?

Answer 13

Synthesises protein when it leaves nucleus, then floats in cytoplasm
Wanders or attaches to Endoplasmic reticulum (rough)

Question 14

What is the Endoplasmic reticulum?

Answer 14

Membrane enclosed passageway that transports materials
Proteins emerge from ER in small vesicles, Golgi body receives them, folds them into reusable products/added lipids/carbs

Question 15

What is the Golgi Complex?

Answer 15

Activates protein created by the ribosome

Question 17

What is the lysosome?

Answer 17

Digests things within cell
Vesicle formed from Golgi complex, contains digestive enzymes

Question 18

What is the peroxisome?

Answer 18

Detoxifies harmful substances?

Question 19

What is the mitochondrion?

Answer 19

Powerhouse of cell, provides energy

Question 20

What is the nucleus?

Answer 20

• Large organelle that houses DNA (genetic material that dictates what cell does)

Question 21

What are microfilaments?

Answer 21

-Composed of proteins actin and myosin
-Most prevalent at edge of cell
-Generates movement, mechanical support (muscles contracting, cell division and locomotion)
-Anchos cytoskeleton to integral proteins in plasma membrane

Question 22

What are the intermediate filaments?

Answer 22

• Composed of several proteins, helps stabilise position of organelles and cells attach to one another
• Found in parts of cells subject to mechanical stress

Question 23

What are microtubules?

Answer 23

• Long branches hollow tubes composed mainly of the protein tubulin, determines cell shape
• Begins in centrosome, grows outwards
• Function in movement of organelles

Question 24

What is matter?

Answer 24

Anything that has mass and occupies space?

Question 25

What does a state of matter depend on?

Answer 25

Temperature, surrounding pressure, strength of forces holding particles together

Question 26

What are the 3 states of matter?

Answer 26

Solid, liquid, gas (indefinite shape and indefinite volume)

Question 27

What are the properties of matter?

Answer 27

Physical property - observable characteristics without changing basic identity of substance (colour, physical state, melting/boiling point, hardness) Chemical property - describes the way the substance undergoes or resists change to form a new substance. Ability to form a new substance (reaction/decomposition)

Question 28

What is pure substance?

Answer 28

Only one substance present Definite and constant composition Properties always the same under same conditions

Question 29

What are elements?

Answer 29

Cannot be broken down into smaller substance by chemical or physical means Building blocks for all other types of matter 118 known elements

Question 30

What is a compound?

Answer 30

Can be broken down into constituent elements by chemical means only Has definite, constant elemental composition

Question 31

What is a mixture?

Answer 31

Physical composition of two or more substances Composition can vary

Question 32

What is a homogenous mixture?

Answer 32

One visible phase Same properties throughout

Question 33

What is a heterogenous mixture?

Answer 33

Two or more visible phases Different properties at different stages

Question 34

What is the atomic number?

Answer 34

Number of protons

Question 35

What is the mass number?

Answer 35

Number of protons and neutrons

Question 36

What is the net charge?

Answer 36

How protons and electrons balance each other out. (Neutral - balanced)

Question 37

What is an ion?

Answer 37

An atom what a net charge - positive or negative

Question 38

Are electrons positive or negative?

Answer 38

Negative

Question 39

What is an atom?

Answer 39

Smallest particle of an element that can exist and still have the properties of the element.

Question 40

What are the atoms essential for life?

Answer 40

Carbon, hydrogen, nitrogen, oxygen

Question 41

What are the subatomic particles?

Answer 41

Protons (+), electrons (-) and neutrons

Question 42

What is a molecule?

Answer 42

Group of two or more atoms that function as unit, tightly bound. Same elements

Question 43

What is the difference between a diatomic and homatomic molecule?

Answer 43

D - contains two atoms. H - all atoms are the same type of element

Question 44

What is a compound?

Answer 44

Two of more atoms of different elements present tightly pound

Question 45

What is an isotope?

Answer 45

Atoms of an element that have the same number of protons and the same number of electrons (but different number of neutrons). Same chemical properties, slightly diff physical properties. Naturally occur range from 2 to 10