Intro To Cellular Anatomy

Question 1

Unifying themes of bio

Answer 1

1. Cell theory:
   1) basic unit of life
   2) all living thing made of cells
   3) cells arise from other cells
2. Molecular basis of inheritance: continuity of life (faithful copying and transmission of DNA for proper functioning of cell)
3. Relationship b/w structure & function
4. Evolutionary change (diversity of life) vs Evolutionary conservation (common elements of living systems)
5. Living systems in equilibrium
   1) open & far from thermodynamic equilibrium
   2) Enzymes catalyze cellular rxn
   3) behaviour of individuals unpredictable from nature of units
6. Info found in DNA dictate cell type & activity (cell receptors dictate gene expression)

Question 2

Cellular Anatomy

Answer 2

1. Cytoplasmic membrane (structure of cell, cell transport, signalling)
2. Nucleus
   1) Nucleus (chromatin, loosely packed DNA, carries genetic info in cell)
   2) Nucleolus (darker region of nucleus, genes for transcription of rRNA & production of ribosomes)
   3) Nuclear membrane (envelops, contains nuclear matter)
   4) Nuclear pore (pores in membrane, allow passage of material b/w cytoplasm & nucleus)
3. Ribosomes (protein factories of cell)
   1) made of protein & rRNA
   2) use code from mRNA & tRNA (synthesize proteins)
   3) free or membrane bound

Question 3

Rough endoplasmic reticulum

Answer 3

1) surface = ribosomes
2) site of protein synthesis (transport from cell, localization to vacuoles, or embedding in plasma membrane)
3) Glycosylation (protein + carb = modified)

Question 4

Smooth endoplasmic reticulum

Answer 4

1) no ribosomes
2) carb, steroid hormone, lipid synthesis
3) controls intracellular Ca2+ levels
4) detoxification

Question 5

Golgi Complex

Answer 5

1) individual sacs of cisternae
2) collection, packaging, sorting, & distribution of molecules
3) molecules cis to trans face of golgi complex (to exterior of cell)

Question 6

Lysosomes

Answer 6

1) arise from golgi complex
2) digestive enzymes = degrade proteins, lipids, carbs
3) defence against pathogens, breakdown of old organelles & cellular waste

Question 7

Endomembrane System

Answer 7

1) compartmentalize cell
2) molecular transport
3) surface for molecular synthesis

Question 8

Microbodies

Answer 8

1) membrane bound vesicles w/ enzymes

2) ex: peroxisomes (oxidative enzymes = produce hydrogen peroxide, breakdown of long chain fatty acids)

Question 9

Vacuoles (plants -central vacuole - & animals)

Answer 9

Membrane: Tonoplast

Channels for water exchange (controls tonicity, intercellular ion concentration, of cell); Water storage & equilibrium

Store & segregate toxins & waste from rest of cell

Question 10

Mitochondria (both plants & animals)

Answer 10

Metabolizes sugar (produce ATP)

Bacteria size, own DNA, own ribosomes (metabolic specific genes)

Question 11

Chloroplasts (only in plants)

Answer 11

Energy from sunlight (create sugar & ATP)

Own DNA & ribosomes

Question 12

Endosymbiotic theory

Answer 12

1) prokaryotic cells first
2) aerobic bacteria: cells compartmentalize, become eukaryotic cells
3) Mitochondria came first (in plants & animals) from bacteria
4) Animals, fungi, certain protists: stay with mitochondria only
4) Plants & certain protists: photosynthetic bacteria adds & becomes chloroplasts