Block 1 Lectures

Question 1

Human composition

Answer 1

96.5% oxygen, carbon, hydrogen, and nitrogen

Question 2

Humans have a similar amount of microbes compared to cells

Answer 2

3.7x10^13

Question 3

What makes something larger?

Answer 3

Number of cells, NOT cell size

Question 4

Which cells modulate their size as a response to rates of fluid flow?

Answer 4

Kidney epithelial cells

Question 5

Which cells increase 25% in size during pregnancy due to insulin demand?

Answer 5

Pancreatic beta cells

Question 6

When pancreatic beta cells die proliferation…

Answer 6

increases but not cell size

Question 7

Liver size increases during pregnancy via…

Answer 7

hepatocyte hypetrophy

Question 8

Liver regeneration after surgery occurs by…

Answer 8

increased hepatocyte proliferation

Question 9

Are humans in equilibrium?

Answer 9

No we are typically in steady-state

Question 10

Negative feedback loops

Answer 10

Loops that correct for a change from a set point (more common)

Question 11

Cell swelling

Answer 11

Osmotic effect of macromolecules that are fixed in a cell because they cannot pass through the membrane

Question 12

Most abundant cell

Answer 12

Red blood cells

Question 13

Endocrine communication

Answer 13

Via blood stream

Question 14

Paracrine communication

Answer 14

Message to neighboring cells

Question 15

Autocrine communication

Answer 15

Message to self-cell

Question 16

Amphipathic

Answer 16

Both polar and nonpolar parts

Question 17

Glycerophospholipid

Answer 17

Amphipathic
Glycerol backbone
2 fatty acyl tails in ester linkage

Question 18

Sphingolipids

Answer 18

Amphipathic
Sphingosine backbone
1 fatty acide tail in amide linkage

Question 18

Main lipid constituent of plasma membrane

Answer 18

Glycerophospholipids (phospholipids)

Question 19

Cholesterol

Answer 19

Amphipathic
Sterol
Essential membrane component
Effects fluid by interacting with hydrocarbon groups on phospholipid tails

Question 20

Sodium concentration

Answer 20

HIGH outside LOW inside

Question 21

Potassium concentration

Answer 21

LOW outside HIGH inside

Question 22

Chloride concentration

Answer 22

HIGH outside LOW inside

Question 23

If K+ channels are open…

Answer 23

membrane voltage is negative

Question 24

If Na+ channels are open…

Answer 24

membrane voltage is positive

Question 25

Nernst equation

Answer 25

Calculates the membrane potential when an ion is at equilibrium