First Unit Test: 2.1, 2.2, 1.1, 1.5, 1.2, 1.3, and 1.4

Question 1

Anabolism

Answer 1

the synthesis of complex molecules from simpler molecules including the formation of macromolecules from monomers by condensation reactions

Question 2

Catabolism

Answer 2

the breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers

Question 3

Cohesive Properties of Water: Explanation and Examples

Answer 3

hydrogen bonds connect water molecules to other water molecules very strongly
- helps the transport of water against gravity in xylem of plants
- causes spilled water to form into droplets
- allows water to have a high surface tension (certain
organisms can live on water surface)
- causes water to have a high boiling point

Question 4

Adhesive Properties of Water: Explanation and Examples

Answer 4

water’s dipolarity causes strong attraction to many other organic substances
- as it travels up the xylem (vascular tissue in plants), water forms hydrogen bonds with the cell walls (cellulose) of plants, helping to counter the effects of gravity (capillary action) as water molecules move up through a plant

Question 5

Thermal Properties of Water: Explanation and Examples

Answer 5

as water molecules absorb heat, the hydrogen bonds between these molecules break before the water molecules themselves can begin absorbing heat and moving faster giving water a high Specific Heat (can absorb or give off a lot of heat without changing temperature by much)
- acts as an environmental temperature stabilizer (internal and external)

because a great deal of heat must be absorbed by water in order to break the hydrogen bonds between the molecules before evaporating, water has a high Heat of Vaporization
- evaporative cooling (transpiration, sweating)

Question 6

Solvent Properties of Water: Explanation and Examples

Answer 6

the majority of organic compounds are polar (like water) meaning that water can act as a solvent and therefore a means of transportation for most organic compounds - it is also the medium of most metabolic reactions
- glycolysis/ protein synthesis in the cytoplasm of cells
- DNA replication/ transcription in the nucleoplasm of cells
- light-independent reactions of photosynthesis in the stroma (fluid) inside the chloroplast
SOLVENT OF LIFE

Question 7

Three Tenants of Cell Theory

Answer 7

1. All living things are made up of cells
2. All cells come from other cells
3. Cells are the smallest unit of life

Question 8

Limitations to Cell Theory

Answer 8

1. Muscle fibers are much larger than other animal cells and may have several hundred nuclei per “cell”
2. Fungal hyphae have hyphas (“cells”) that can have many nuclei each
3. Giant algae can grow as large as 100 nm yet only has 1 nucleus
   * challenge our common understanding of what a cell is

Question 9

Metabolism in Paramecium & Chlorella

Answer 9

P: food particles are enclosed within small vacuoles containing enzymes
C: metabolic pathways take place in the cytoplasm

Question 10

Reproduction in Paramecium & Chlorella

Answer 10

P: asexual division via fission
C: grows and replicates via interphase, nucleus divides via mitosis, cell divides via cytokinesis

Question 11

Response in Paramecium & Chlorella

Answer 11

P: cilia moves the cell
C: chlorophyll captures sunlight

Question 12

Homeostasis in Paramecium & Chlorella

Answer 12

P: O2 enters and CO2 exits the cell via diffusion
C: stores excess glucose as starch

Question 13

Excretion in Paramecium & Chlorella

Answer 13

P: solid waste exits through anal pore, liquid exits via vacuoles
C: plasma membrane controls exit of substances

Question 14

Nutrition in Paramecium & Chlorella

Answer 14

P: cytostome engulfs food
C: photosynthesis in chloroplasts

Question 15

Growth in Paramecium & Chlorella

Answer 15

P: expands until dividing (after getting food)
C: expands until dividing (after metabolizing glucose)

Question 16

Stem Cells: Stargardt’s Disease

Answer 16

embryonic stem cells are used to halt/slow down the loss of retinal cells and retain/improve vision

Question 17

Stem Cells: Rheumatoid Arthritis

Answer 17

mesenchymal stem cells are used to repair damaged tissue throughout the body and reduce pain/increase mobility

Question 18

Endosymbiotic Theory: Evidence

Answer 18

• mitochondria are similar in size to prokaryotes, divide, by fission, are equipped to function somewhat independently (ribosomes and proteins, DNA) and have two membranes
• chloroplasts perform photosynthesis like several prokaryotic organisms
• DNA is globally made up of 64 common codons

Question 19

Disproving of Modern Spontaneous Generation

Answer 19

Pasteur’s experiment included three flask samples of sterilized broth; only the open flask showed any bacterial growth
- life no longer comes from “nothing” (if it ever did)

Question 20

Osmosis

Answer 20

diffusion of water across membrane (through special protein channels called aquaporins); often to balance out solute concentrations (water moves from areas of low (hypotonic) solute concentration (high water) to areas of high (hypertonic) solute concentration (low water)

Question 21

Simple Diffusion

Answer 21

substances move from areas of high concentration/ high osmolarity (hypertonic solution) to areas of low concentration (hypotonic solution) to balance them out - DOWN a concentration gradient
- uses either the phospholipid bilayer or non-specific protein channels

Question 22

Facilitated Diffusion

Answer 22

diffusion of large molecules/ ions through highly specific protein carriers/ channels (proteins change shape to “facilitate” this – rate of transport levels off with saturation of proteins)

Question 23

Endocytosis

Answer 23

the fluidity of the membrane allows it to change shape so parts of it can be “pinched off” to form vesicles around larger molecules/ fluids/ structures to move them into the cell

Question 24

Exocytosis

Answer 24

substances produced inside the cell (or its organelles) are processed and packaged in vesicles, which will fuse with the cell membrane and release their contents to the extracellular space

Question 25

Sodium-Potassium Pump

Answer 25

proteins change shape and expel sodium ions and release potassium ions into the interior

Question 26

Davson-Danielli into Singer-Nicolson

Answer 26

• Davson-Danielli (1935) suggested that the lipid bilayer was covered on both sides by a thin layer of protein based off of electron micrographs that made it appear as two protein layers encasing a third lipid layer
• further experimentation proved that not all membranes are identical and can have different functions, compositions and structure
• a protein layer is also unlikely because it would be largely non-polar
• Singer-Nicolson (1972) proposed that proteins are inserted into the phospholipid bilayer and do not form a layer on the bilayer surfaces