MBS Lecture 2

Question 1

What is the size of a typical cell

Answer 1

0,1 mm

Question 2

When was the invention of the telescope

Answer 2

17th century

Question 3

Who inspected thin slides of cork

Answer 3

ROBERT HOOKE

Question 4

What did Robert Hooke discover?

Answer 4

millions of small, irregular units

Question 5

What is the cell theory?

Answer 5

• All cells come from a division of pre-existing cells
• Cells are the building blocks for plants and animals
• Cells are the smallest unit that perform all vital physiological functions
• Each cell maintains homeostasis at the cellular level. Homeostasis at the level of the tissue, organ, organ system, and organism reflects the combined and coordinated action of many cells

Question 6

What are cells surrounded by?

Answer 6

A watery medium, extracellular fluid (interstitial fluid)

Question 6

What does the plasma membrane do?

Answer 6

Separates the cytoplasm from the extracellular fluid

Question 7

What is inside the cytoplasm?

Answer 7

Cytosol

Question 8

What is inside the cytosol?

Answer 8

Organelles

Question 9

What are intracellular structure?

Answer 9

Organelles

Question 10

What are the functions of the plasma membrane?

Answer 10

Physical isolation
- Barrier

Regulates exchange with environment
- Ions and nutrients enter
- Wastes eliminated and cellular products released

Monitors the environment
- Extracellular fluid composition
- Chemical signals

Structural support
- Anchors cells and tissues

Question 11

What is inside the plasma membrane?

Answer 11

Membrane lipids, proteins and carbohydrates

Question 12

What are membrane lipids?

Answer 12

Double layer phospholipid molecules

Question 13

What do phospholipid molecules contain?

Answer 13

Hydrophylic and hydrophobic heads

Question 14

What do hydrophilic heads do?

Answer 14

They move toward watery environment, both sides

Question 15

What do hydrophobic tails do?

Answer 15

They are fatty acid tails that are inside the membrane
They are a barrier to ions and water—soluble compounds

Question 16

Which is polar?

Answer 16

The hydrophilic (polar) head is soluble in water

Question 17

Which is nonpolar?

Answer 17

They have two hydrophobic (nonpolar) tails are not. A tail
has a kink wherever there is an unsaturated bond.

Question 18

What do phospholipids form?

Answer 18

Phospholipids form a bilayer that serves as the major
component of a cell’s plasma membrane. The fluidity of the
plasma membrane is due to kinks in the phospholipids’
tails

Question 19

Types of Membrane proteins:

Answer 19

Integral and Peripheral

Question 20

Where are Integral and Peripheral Proteins?

Answer 20

Within the membrane

Bound to inner or outer surface of the membrane

Question 21

What are the different types of proteins?

Answer 21

Anchoring proteins (stabilizers)
- Attach to inside or outside structures

Recognition proteins (identifiers)
- Label cells as normal or abnormal

Enzymes
- Catalyze reactions

Receptor proteins
- Bind and respond to ligands (ions, hormones)

Carrier proteins
- Transport specific solutes through membrane

Channels
- Regulate water flow and solutes through membrane

Question 22

What are the most important abundant organic

molecules?

Answer 22

Proteins

Question 23

What do proteins contain?

Answer 23

Carbon (C), hydrogen (H), oxygen (O), and nitrogen (N)

Question 24

How many basic building blocks do proteins have

Answer 24

20 amino acids

Question 25

What are the 7 major protein functions?

Answer 25

Support - Structural proteins Movement - Contractile proteins Transport - Transport (carrier) proteins Buffering - Regulation of pH Metabolic regulation - Enzymes Coordination and control - Hormones Defense - Antibodies

Question 26

What is the structure of proteins?

Answer 26

Long chains of amino acids Amino acid structure: Central carbon atom, Hydrogen atom, Amino group (—NH2), Carboxylic acid group (—COOH), Variable side chain or R group

Question 27

What are the building blocks of proteins?

Answer 27

Amino Acids

Question 28

What do all amino acids have in common?

Answer 28

The acidic carboxyl group

Question 29

What distinguishes amino acids?

Answer 29

The different R groups, which gives each amino acid its own chemical properties

Question 30

What are Proteoglycans, glycoproteins, and glycolipids made of?

Answer 30

Pro+carbs - Carbs+Pro - Carbs+lipids

Question 31

Where are they found?

Answer 31

They extend outside cell membrane

Question 32

What do they form?

Answer 32

They form sticky “sugar coat” (glycocalyx)

Question 33

What are the functions of glycocalyx?

Answer 33

Lubrication, Protection, Anchoring, Locomotion, Specificity in binding (receptors) and Recognition (immune response)

Question 34

What are Lipids?

Answer 34

Mainly hydrophobic molecules such as fats, oils, and waxes

Question 35

What atoms are lipids made of?

Answer 35

They are made mostly of carbon and hydrogen atoms

Question 36

What do fatty acids contain?

Answer 36

Long chains of carbon and hydrogen with a carboxylic acid group (COOH) at one end

Question 37

Are fatty acids polar or nonpolar?

Answer 37

They are relatively nonpolar, except the carboxylic group

Question 38

What can fatty acids be?

Answer 38

Saturated or unsaturated

Question 39

Saturated

Answer 39

They have hydrogen (no covalent bonds)

Question 40

Unsaturated

Answer 40

(one or more double bonds): - monounsaturated = one double bond - polyunsaturated = two or more double bonds

Question 41

What do Phospholipids and Glycolipids have?

Answer 41

Diglycerides attached to either a phosphate group (phospholipid) or a sugar (glycolipid)

Question 42

What do BOTH Phospholipids and Glycolipids have?

Answer 42

They generally, both have hydrophilic heads and hydrophobic tails and are structural lipids, components of plasma (cell) membranes

Question 43

Where are Organelles and cytoplasm found?

Answer 43

Inside the cell and outside the nucleus

Question 44

What does the cytosol do?

Answer 44

Dissolved materials: nutrients, ions, proteins, and waste

Question 45

What nutrients are in the cytosol

Answer 45

High potassium/low sodium High protein High carbohydrate/low amino acid and fat

Question 46

What are organelles?

Answer 46

Structures with specific functions

Question 47

What are nonmembranous organelles?

Answer 47

- No membrane - Direct contact with cytosol - Includes the cytoskeleton, microvilli, centrioles, cilia, ribosomes, and proteasomes

Question 48

What are membranous organelles?

Answer 48

- Covered with plasma membrane - Isolated from cytosol - Includes the endoplasmic reticulum (ER), the Golgi apparatus, lysosomes, peroxisomes, and mitochondria

Question 49

Example of a nonmembranous organelle:

Answer 49

The cytoskeleton

Question 50

What does the cytoskeleton do?

Answer 50

They are structural proteins for shape and strength

Question 51

Types of cytoskeleton:

Answer 51

Microfilaments Intermediate filaments Microtubules

Question 52

What are microfilaments?

Answer 52

Thin filaments composed of the protein actin

Question 53

What is the function of microfilaments?

Answer 53

- Provide additional mechanical strength - Interact with proteins for consistency - Pair with thick filaments of myosin for muscle movement

Question 54

What is the function of intermediate filaments?

Answer 54

- Provide strength - Stabilize position of other organelles

Question 55

What is the function of microtubules?

Answer 55

- Provide cell strength, rigidity; anchor organelles - Alter shape of cell; assist in cell movement - Align and move organelles within the cell - Form the mitotic apparatus for cell division - Form centrioles, cilia, and flagella