Prokaryotic and Eukaryotic Cells

Question 1

What are the requirements for a cell’s survival?

Answer 1

Energy, Matter, Simple Nutrients, Removal of Wastes
Cells remain alive as long as the metabolic reactions in the cytoplasm are maintained, if not (with a few exceptions like freezing certain types of cell) the cell dies if metabolism is stopped for any reason.
metabolism takes place in the cytoplasm
In Eukaryotes, the DNA, as chromosomes is contained within a nuclear membrane

Question 2

Energy (requirements for survival)

Answer 2

energy is required by all organisms to grow, reproduce, move and carry out fundamental maintenance and repairs, energy can’t be created/ destroyed main/best energy source is the sun

Question 3

What are Autotrophs and Heterotrophs?

Answer 3

Autotropes are organisms capable of producing their own energy while heterotropes are organisms incapable of making energy (consumers)

Question 4

Photosynthetic Autotrophs

Answer 4

Photosynthetic autotropes = make food using the energy of sunlight- plants, algae and some bacteria

Question 5

Chemosynthetic Autotrophs

Answer 5

derive their energy from inorganic sources such as sulfur and amonia. Some bacteria are chemoautotrophs

Question 6

Chemosynthetic Heterotrophs

Answer 6

consume other organism to obtain their energy and carbon sources

Question 7

Photosynthetic Heterotrophs

Answer 7

able to convert light energy, but still require organic compounds such as a carbon source. Some bacteria are photoheterotrops

Question 8

What do cells require?

Answer 8

They require matter (oxygen and carbon dioxide), photosynthesis and respiration involves these gases

Question 9

CELLS REQUIRE SIMPLE NUTRIENTS

Answer 9

Every living cell is involved in synthesizing large molecules (biomarcomolecules) that are required for growth and biomechanical processes required for survival.

Question 10

What are the biomarcomolecule groups?

Answer 10

Carbohydrates, Lipids, Proteins and Nucleic Acids

Question 11

Types of Carbohydrates

Answer 11

monosacchride- single sugar molecules (eg. glucose)

diasacchride - two sugar molecules linked (eg. sucrose)

polysacchride- many sugar molecules (eg. pasta)

Question 12

What are amino acids?

Answer 12

Cells require proteins that are composed of amio acid chains. Essential amino acids are obtained from diet but non-essential are produced in the body, there are over 500 amino acids in nature but human DNA only codes 20
amino acids —> peptides —> proteins

Question 13

What is a proteins role? (6)

Answer 13

Enzyme reactions, structure, storage, transport, Defense , respiration
DESSRT

Question 14

Cells require Lipids (biomacromolecule)

Answer 14

A lipid is made up of 3 fatty acids joined to a glyecerol molecule

Lipids are a diverse group of molecules such as fats, oils, steroids and cholesterol

Lipids contain carbon (C), hydrogen (H) and oxygen (O) but in a different ratio to carbohydrates

high energy that may be released in respiration (2x that of carbohydrates)

Question 15

Cells require Nucleic Acids (biomacromolecule)

Answer 15

Nucleic acids are made up of chains called nucleotides.

For example:
- DNA (deoxyribunic acid), double stranded molecule used to make up chromosomes, found in the nucleus

• RNA (ribose nucleic acid) found in the nucleus/ other parts made up of single chains
• ATP (adenosine triposphate) is a carrier molecule, carries energy from one chemical reaction to another.

Question 16

Cells require water and ions

Answer 16

Water is a good solvent, many chemicals dissolve in it and water is used in the boyd for brain, circulation, cells , kidneys, skin, heart

Ions- sodium and chloride are required by neurons to transmit electrical messages. Nitrate and phosphate ios are needed by plants/ animals to make proteins

Question 17

CELLS NEED TO REMOVE WASTES

Answer 17

Cellular products are often produced in one part of the cell and used in another part. Wastes must be removed and transported out of the cells - carbon dioxide and water

Question 18

Living things

Answer 18

Living things - non cellular - viruses

                  - cells  - prokaryotic (relatively small cells 0.5- 10 micrometers)  - bacteria cells
                  - eukaryotic cells (relatively large cells 30-150 micrometers) - fungal cells, protistan cells, animal cells, plant cells,

Question 19

PROKARYOTES

Answer 19

• no internal membrane organelles
• no true nucleus (no membrane)
• genetic material in the nucleic area, but is not separated from other cell material by membrane
• genetic material in the form of single circular chromosomes
• prokaryotes typically unicellular organisms and are generally smaller than EC
• exist as single cells

Question 20

EUKARYOTES

Answer 20

• characterized by having their genetic material contained within a nuclear membrane
• larger than PC
• more complex cellular organisms- variety of internal membranes/ structures called organelles
• specialized organs facilitate the following:
  photosynthesis, cellular respiration
  synthesis of complex molcecules, removal of cellular products and wastes
  Fungi, protists, animals and plants are all EC
  EC organisms can be unicellular (protists) or multicellular (plants)

Question 21

Common Evolutionary Past

Answer 21

The Emdosymbiotic theory proposes that EC were formed when a bacteria was ingested by another primitive PC in a process called phagocytosis

The engulfed prokaryotic cell remained undigested as it contributed new functionality to the engulfing cell (eg. photosynthetis)

Over generations, the engulfed cell lost some of its independent untility and became a supplemental organelle

Question 22

The Functions of Organelles

Answer 22

nucleus- control center
golgi body-  packaging department 
endoplasmic reticulum - transport system
mitochondria - power supply
ribosomes- assembly lines 
lyosomes- repair and maintenance.

Question 23

Nucleus - control centre

Answer 23

contains all of the DNA which is packaged in chromosomes that code for the production of proteins
the control centre directing the production of proteins
DNA is similar in every cell of the body, but depending on the specific cell type, some genes may be turned on/off explaining how cells differ from each other

Question 24

Nucleolous

Answer 24

The main structure in the nucleus that produces ribosomes, which move out of the nucleus and take positions on the rough Endoplasmic reticulum where they are critical in protein synthesis

Question 25

Cell Membrane

Answer 25

plasma membrane every cell is encosed in a membrane which regulates the entry and exit of substances so as to protect the cell's internal enviroment the cell's outer membrane is made up of mix of proteins and lipids the lipids give the membrane flexibility and the proteins transmit chemicals q

Question 26

Cell Wall (plant cells only)

Answer 26

provides and maintains the shape of plant cell serves as a protective barrier fluid collects in the vacuole and pushes against the cell wall (the tugor pressure is responsible for the crispness of fresh vegetables)

Question 27

Energy Related Oragnelles

Answer 27

Chloroplasts and mitochondira are the two energy-related organelles in EC House energy in the form of ATP Chloroplasts are known as plastids which are major organells found in the cells of plants and algae. They are the site of the manufacture and storage of important chemical compounds used by the cell eg. pigments, tannins and polyphenols. Chloroplats are involved in photosynthesis

Question 28

Chloroplasts structure

Answer 28

plastics containing the green pigment chlorophyll inside chloroplasts are stacks of flatted sacs called thylakoids each thylakoid contains chlorophyll molecules

Question 29

Mitochondria

Answer 29

mitochondria provide the energy a cell needs, to move divide and produce products such as Enzymes membrane bound organelles found in almost all EC The inner membranes (folds) are called cristae which contain protein complexes that produce ATP the fluid inside (matrix) contains enzymes that break down carbohyrates

Question 30

Ribosomes

Answer 30

packets of genetic material (RNA) Ribosomes can be attached to rough endoplasmic reticulum or remain free in the cytosol protein synthesis takes place on the ribosome and build amino acids into complex proteins

Question 31

Endoplasmic reticulum

Answer 31

``` smooth ER (without ribosomes) and is the site of protein synthesis and processing rough ER (with ribosomes) and is the site of protein synthesis and processing ```

Question 32

Golgi Bodies

Answer 32

specialised areas of the endoplasmic reticulum form small sacs- vesticles that break off and transport substances to the cell membrane once some proteins are produced (synthesised), they can be stored in the Golgi bodies then transported in vesticles to other parts of the cells/membrane where they are released from the cell

Question 33

Lyosomes

Answer 33

lyosomes are vesicles produced by the golgi apparatus and contain enzymes and are involved in intracellular digestion they recycle the materials as nutrients (or building blocks) vacuoles (large) and vesticles (small) store substances

Question 34

Vacuoles

Answer 34

small in animal cells/large in plant cells store nutrients and waste products help increase cell size during growth digest materials like lysomes regulates tugor pressure in the cell water collects in the cell vacuoles pressing outward against cell wall producing rigidity without sufficient water, tugor pressure drops and the plant wilts

Question 35

cytoplasm

Answer 35

contains the organelles (specalised structures) of the cell and sugars, amino acids, proteins that cell uses for growth and reproduction cytoplasm encases, cushions and protects the internal organelles