ABPI 311 - Cells

Question 1

Number of chromosomes in humans?

Answer 1

23

Question 2

Contrast hyperplasia and hypoplasia.

Answer 2

Hyperplasia - too many of certain cell type in an organ.

Hypoplasia - too few of certain cell type in the organ.

Question 3

Contrast hypertrophy and hypertrophy.

Answer 3

Hypertrophy - cells larger than normal size

Hypotrophy - cells smaller than normal size

Question 4

Atrophy is?

Answer 4

Gland size regression.

Question 5

Contrast catabolism and anabolism.

Answer 5

Anabolism part of metabolism that BUILDS (proteins, amino acids, etc)
Catabolism part of metabolism that BREAKS (glycolysis, krebs, etc)

Question 6

Endoplasmic Reticulum - form and function.

Answer 6

Form: adjacent to nucleus. Ribosomes on it make it ROUGH ER, lack of ribosomes SMOOTH ER.

Function: protein synthesis and transport of proteins away from nucleus.

Question 7

Mitochondria - Form and function.

Answer 7

Form: located throughout cell, numbers vary depending on cell type, filled with internal invaginations increasing internal SA.

Function: cellular powerhouse, oxidizes nutrients to form CO2, water, ATP.

Question 8

Lysosomes - form and function.

Answer 8

Form: small membrane bound sacs of enzymes.

Function: aids in breaking down components into useable or non-pathogenic forms for further processing. Over 50 digestive enzymes.

Question 9

Cytoskeleton - form (3 protein filaments are?) and function.

Answer 9

Form: 3 primary protein filaments are microtubules, actin filaments, and intermediate fibres. Located throughout cell attaching to membranes and organelles.

Function: cell motility, cell shape, size, movement of organelles and other internals. MUSCLE CELL CONTRACTION.

Question 10

Microtubules - function.

Answer 10

Assist in internal movements of cell.

Transport of molecules within cell.

Question 11

Micro filaments - functions.

Answer 11

Assist with cell motility.

Question 12

Actin and intermediate fibres - function.

Answer 12

Assist in muscle contraction.

Question 13

Nucleus - form and function.

Answer 13

Form: largest organelle in nucleated cells. Surrounded by double layered nuclear membrane permeated with nuclear pores. Dark spot within is nucleolus.

Function: genetic information exits, only products tagged with NLS (nuclear localization signal) may enter, cells “brain” primary cite of genetic replication.

Question 14

Ribosomes - form and function.

Answer 14

Form: usually located on RER adjacent from nucleus.

Function: receive mRNA from nucleus and translate to make proteins.

Question 15

Cell Membrane - form and function.

Answer 15

Form - phospholipid bilayer interspersed with proteins, carbohydrates, and pores (protein channels).

Function - control entry, exit, of material in cell. Maintains cell integrity. Membrane proteins and carbohydrates aid in communication to and from other cells.

Question 16

Membrane types (3)

Answer 16

Permeable - lets most molecules pass.
Semi-permeable - lets select number of molecules pass.
Impermeable - molecules cannot pass.

Question 17

Types of cell transport (3)

Answer 17

Diffusion (osmosis) - lipid soluble and water diffuse across. Water, O2, CO2.

Passive transport (facilitated diffusion) - water soluble and water diffuses through interior of transport proteins. NO ENERGY REQUIRED.

Active transport - Specific salutes are pumped through interior of transport proteins. ENERGY REQUIRED. Against concentration gradient.

Question 18

Endocytosis and exocytosis.

Answer 18

Endocytosis - 1) phagocytosis - cell eating, engulfs external material in vesicle to bring in. 2) Pinocytosis - cell drinking, surrounds liquid forms vacuole.

Exocytosis - cell deposits material originating internally to external via release of vacuole at cell membrane.

Question 19

Types of junctions (2)

Answer 19

Tight junctions - tight between two adjacent cells prevent movement between them.

Gap junctions - space between two adjacent cells allow flow of some particles. ** permits change of membrane potential in nerve cells via ion flow.

Question 20

Apical vs basolateral surface.

Answer 20

Apical surface is facing lumen.

Other parts (usually touching only ECF) are basolateral.

Applies to only tight junctions.