LEC 7

Question 1

Cell Theory (3)

Answer 1

1. All living things are composed of cells and cell products.
2. A single cell is the smallest unit that exhibits all the characteristics of life.
3. All cells come only from preexisting cells.

Question 2

Eukaryotic cell (4)

Answer 2

1. Has cell membrane
2. Membrane-bound nucleus with DNA
3. Cytoplasm (with gel-like fluid called cytosol)
4. Membrane-bound organelles designed for specialized functions

Question 3

Prokaryotic cell

Answer 3

1. Simplest cells
2. Nucleoid - DNA containing inner region (not membrane bound)
3. Cell membrane & rigid cell wall
4. No membrane bound organelles
5. Divide rapidly

Question 4

All cells do what 4 things?

Answer 4

1. Gather raw materials
2. Excrete wastes
3. Make macromolecules
4. Grow and reproduce

Question 5

Why are all cells small?

Answer 5

the larger the cell gets, the more likely that its growth and metabolism will be limited by its ability to supply itself across the plasma membrane
Smaller is more efficient!!!

Question 6

Microvilli

Answer 6

Microscopic projections that extend outwards from the cell
Increase surface area

Question 7

Types of microscopes

Answer 7

Light microscope
Transmission electron microscope
Scanning electron microscope

Question 8

Light microscope

Answer 8

can magnify a sample up to 1000 times

Question 9

Transmission electron microscope (2)

Answer 9

makes 2D image of the outer surface using electrons
Can magnify up to 100,000 times

Question 10

Scanning electron microscope (2)

Answer 10

makes the 3D image of the outer surface using electrons
Can magnify up to 100,000 times

Question 11

Nucleus (2)

Answer 11

control centre of the cell
has most the genetic material

Question 12

Parts of Nucleus (3)

Answer 12

1.Nuclear membrane
2. Nucleolus
3. Nuclear pores

Question 13

Nucleolus (2)

Answer 13

Dense region inside nucleus
Components of ribosomes form here and pass through pores to enter cytoplasm

Question 13

Nuclear membrane (2)

Answer 13

Double layer of phospholipids
Surrounds the DNA & keeps it inside the nucleus

Question 14

Nuclear pores (2)

Answer 14

Selectively allows materials (ribosomes, proteins and RNA) to move in/out
Too small for DNA to leave through

Question 15

Ribosomes def

Answer 15

Involved in assembling amino acids in the correct sequence (primary structure) into specific protein chains

Question 16

Where are ribosomes found? (2)

Answer 16

1. Float in cytoplasm
2. Attach to the rough ER

Question 16

How are ribosomes formed? (3)

Answer 16

1. Parts of RNA and ribosomal proteins are formed
2. Parts leave the nucleus via nuclear pores
3. Enter the cytoplasm and are assembled into ribosomes

Question 17

Where are ribosomes formed?

Answer 17

nucleolus

Question 18

Endomembrane System (4 organelles)

Answer 18

1. Rough Endoplasmic Reticulum (production)
2. Smooth Endoplasmic Reticulum (packaging)
3. Golgi Apparatus (labelling)
4. Specialized vesicles (shipping)

Question 19

Endoplasmic Reticulum def

Answer 19

Works with ribosomes to synthesize most of the chemical compounds made in the cell

Question 20

Endoplasmic Reticulum structure

Answer 20

1. Repeated folded membrane structure
2. Fluid filled
3. some of it is connected to the nuclear membrane
4. form transport vesicles to move synthesized materials out of the cell

Question 21

Endoplasmic Reticulum types

Answer 21

rough ER
smooth ER

Question 22

Rough ER to Smooth ER

Answer 22

1. Involved in protein synthesis (on the outside)
2. Once synthesized, proteins enter the fluid-filled space of rough ER
3. Proteins enter the smooth ER

Question 22

Rough ER structure (3)

Answer 22

repeated folded physically connected to the nuclear membrane dotted with ribosomes

Question 23

Smooth ER def

Answer 23

1. Synthesis of macromolecules (lipids and some hormones) Packaging centre for proteins & lipids that were synthesized by both the rough endoplasmic reticulum and smooth endoplasmic reticulum

Question 24

Smooth ER to Golgi bodies

Answer 24

1. Smooth ER sends “package” to the Golgi apparatus through vesicles (that form from membrane of smooth ER) 2. Pinch off

Question 25

Golgi Apparatus def

Answer 25

Processes and packages proteins and lipid molecules

Question 26

What happens inside the Golgi body? (4)

Answer 26

1. Enzymes refine and complete proteins 2. Adds “label” that indicates where product should be sent 3. Sorts and packages products 4. Forms vesicles that “ship” products to their final destination

Question 27

How does the Golgi body receive transport vesicles? (2 )

Answer 27

1. Vesicles fuse with the fluid-filled membrane layer of the Golgi apparatus 2. Empty contents to the inside

Question 28

Where does lipid synthesis happen?

Answer 28

Inside Golgi body

Question 29

What are secretory vesicles made up of?

Answer 29

Golgi body membrane

Question 30

What are secretory (exocytotic) vesicles for?

Answer 30

1. Has products destined for export from the cell 2. Release contents to the outside of the cell

Question 30

How do lipids leave the Golgi body?

Answer 30

through vesicles

Question 31

What are endocytotic vesicles for?

Answer 31

Enclose bacteria & raw materials from the outside of the cell and bring them inside

Question 32

What do peroxisomes do? (2)

Answer 32

1. Vesicles that contain powerful enzymes 2. Used to destroy toxic wastes produced in the cell

Question 33

What kind of toxic waste do peroxisomes destroy?

Answer 33

alcohol meds drugs

Question 34

What do lysosomes do? (3)

Answer 34

1. Contain powerful digestive enzymes 2. Fuse with endocytotic vesicles and digest bacteria and other large particles 3. Conduct “housekeeping” tasks (lysis of anything not required)

Question 35

Mitochondria (2)

Answer 35

powerhouse of the cell (make ATP) cellular respiration (in the presence of O2)

Question 36

Main sources to create energy (3)

Answer 36

1. Fats 2. glucose 3. glycogen

Question 37

How many mitochondria are in each cell?

Answer 37

Depends on the cell's needs (muscle cells will have more while nerve cell mitochondria)

Question 38

Mitochondria structure

Answer 38

1. Double membrane system 2. own DNA and ribosomes

Question 39

Mitochondria OUTER membrane structure

Answer 39

smooth

Question 40

Mitochondria INNER membrane structure (2)

Answer 40

1. Deeply folded (cristae) 2. Has enzymes bound to it

Question 41

What happens inside the mitochondria's INNER membrane?

Answer 41

Enzymes catalyze reactions to release energy

Question 42

Cytoskeleton

Answer 42

1. Helps cell membrane maintain its shape 2. Support and anchors other structures within the cell

Question 43

Cytoskeleton network is made up of: (2)

Answer 43

1. Microtubules 2. Microfilaments

Question 44

Microtubules

Answer 44

tiny hollow tubes

Question 45

Microfilaments

Answer 45

thin solid fibres

Question 46

How is the cytoskeleton network constructed?

Answer 46

microtubules and microfilaments connect to each other and the glycoproteins in the cell membrane

Question 47

Cilia purpose

Answer 47

move materials along the cell surface with a brushing motion

Question 48

What are cilia made up of?

Answer 48

microtubules

Question 49

Cilia length and numbers

Answer 49

short

Question 50

Flagella purpose

Answer 50

movement of the organism

Question 51

What are flagella made up of?

Answer 51

microtubules

Question 52

Flagella length and numbers

Answer 52

long and few

Question 53

Centrioles (2)

Answer 53

1. Short, rod-like microtubular structures 2. Located near nucleus

Question 54

How are centrioles used in cell divison?

Answer 54

Alignment and division of genetic material