Intro to cell/physiology lecture 1

Question 1

Homeostasis

Answer 1

a healthy balance that our body tries to maintain to keep us alive.

Question 2

Metabolic waste/byproducts

Answer 2

H+ (protons) or CO2

Question 3

How do we rid the body of H+? Is it a long or short term process?

Answer 3

All protons have to be dealt with by the kidneys at some point but this can take hours-days. (long term)

Question 4

How do we rid the body of CO2? Is it a long or short term process?

Answer 4

CO2 can be dealt with by the lungs. (Short term)

Question 5

Examples of nutrients for our cells to function

Answer 5

Glucose, Fatty acids, etc

Question 6

Negative Feedback

Answer 6

A major control system in the body. The body senses a change and stimulates an opposite/counter change. (Schmidt’s words: we see a change, the body responds to fix the change)
ex: change: increase CO2 -> body stimulates: increased ventilation -> result of stimulation: decreased CO2

Question 7

How does the body increases ventilation?

Answer 7

1st it increases TV

2nd it increases RR

Question 8

Where are CO2 sensors located?

Answer 8

Brain stem, carotid arteries, and heart

Question 9

Positive Feedback

Answer 9

A major control system in the body. The body senses a change and responds by amplifying the change.(Schmidt’s words: We see a change, the body amplifies the change until a safety mechanism stops it or we die) ex: Bleeding. We start to clot. Clotting stimulates more clotting. The clotting stops when we stop bleeding (checkpoint)

Question 10

What is it called when a positive feedback goes bad? give example

Answer 10

Vicious cycle.
ex: Blood can clot around uneven vessel walls. Clotting stimulates more clotting. No checkpoint. Blood will clot until vessel is occulted. …and we die

Question 11

What makes up the inside of a cell? (by most prevalent)?

Answer 11

Water (70-85%), Protein (10-20%), Lipids (remaining)

Question 12

What do proteins inside the cell do?

Answer 12

Some just sit and take up space. Some do chemical work and are called enzymes

Question 13

The cell wall is made up of…

Answer 13

a phospholipid bilayer

Question 14

The tails of a phospholipid are made up of…

Answer 14

Fat molecules (lipids). Specifically, carbons single bonded together in kinks with hydrogens bonded to open sites on the carbons.

Question 15

words to describe lipid tails:

Answer 15

no charge
non-polar
more "oil" like
fats
hydrophobic
lipiphilic

Question 16

words to describe the phosphate head

Answer 16

charged (usually negative)
polar
more "water" like
hydrophilic
lipiphobic

Question 17

Amphipathic

Answer 17

has 2 natures. refers to the phospholipid bilayer having a lipid soluble and water soluble portion.

Question 18

how does water get though cell walls?

Answer 18

Water is freely permiable with the help of passive channels. It is not actively pumped therefore no energy is expelled. Movement is triggered by the differences in osmolarity.