A&P Lab - Class 2: Chemistry and the Cell

What are component ions?

Positive cations and negative anions

What are compounds?

Substances that contain atoms of 2+ elements

4 major groups of organic molecules

- Carbs
- Lipids
- Proteins
- Nucleic acids

What is the most abundant inorganic compound in the body?

Water

How much of blood plasma is water?

About 90%

What do acids do with hydrogen ions when they're dissolved in water?
Why is this?

Releases H+.
Hydrogen is a free proton. This is why acids are known as proton donors.

Why are bases known as proton acceptors?

They're substances that bind to (accept) H+ (protons).

What is happening when OH- is released in water?

A base is being dissolved in water

What is the relationship between water and chemical reactions?

Water is the medium for most chemical reactions

What is water a good solvent for?
Why is this?

It's a great solvent for ionic and polar substances because water is polar itself.

pH is a concentration of _____________.
How is this measured?

Hydrogen ions, measured by moles/L

If we change one pH unit, what does this change equate to?

One pH unit change = a tenfold change in hydrogen ion concentration

What is a normal blood pH?
How is this regulated?

7.35 - 7.45, regulated by homeostasis

What is the relationship of bicarbonate ions (HCO3-) in the body?

They're an example of a base which is produced in the human body. They're abundant in the blood and act to decrease the effect of hydrogen ions.

What is the role of a buffer?

They resist large changed in pH:
- Release H ions when pH begins to rise
- Bind H ions when pH begins to drop

What is Neutral Red?
How does an acidic, neutral, and basic solution affect Neutral Red?

Neutral Red is an acid-base colour indicator.
- Acidic solution: Magenta/purple
- Neutral solution: Red (unchanged)
- Basic solution: Yellow/orange

What is another word for pH strips?

Litmus paper

What is the pH of stomach acid (HCl)?

1-3

When added to hydrochloric acid, what do antacids bring the pH to?

7 (neutral)

How do antacids work?

Metals such as magnesium or calcium bind to a base (hydroxide or carbonate)

What is the role of buffers in physiological solutions?

To neutralize acids and help maintain homeostasis

What colour would occur if Neutral Red was added to the contents of your stomach?

Magenta

Solution "X" was mixed with a small amount of Neutral Red. This mixture turned a yellow-orange colour. What does this result indicate about the pH of solution "X"?

It's basic

What does iodine react with which causes a solution to turn blue?

Starch

What does Benedict's reagent react with in order for it to turn from blue to red when heated?

Sugar

Organic compounds contain ______ and are able to form up to ______________ bonds

contain carbon, form up to 4 covalent bonds

True or False: Starch is a polysaccharide

True

In studies, why is it important to have solutions of distilled water?

To act as a control group. No study is valid without a control.

What are examples of what we're trying to avoid by using a control group in a biology lab?

Monitoring for colour change, precipitates, cloudiness, etc. that could be attributed to the introduction of reactionless substances.

Alcohol is (polar/nonpolar)

Nonpolar

There is a greasy food stain in your clothing. Will you use water or alcohol to clean it?
Why?

Alcohol.
Its nonpolarity can break apart fats (lipids) when water (polar) cannot. Lipids are hydrophobic.

Biuret turns from transparent to purple in your solution. What does this mean that the solution contains?

Protein

What is albumin?

A plasma protein

If biuret comes into contact with the skin, it will turn the skin purple. Why is this?

The skin contains a lot of protein (keratin)

What are the components of nucleic acids?

Carbon, hydrogen, oxygen, nitrogen, phosphorus

During this lab, many mitochondria could be viewed in the ________ cell (squamous epithelial/liver)
Why is this?

Liver.
This is because the liver requires a lot of energy to do its vast functions, and requires lots of mitochondria in its cells for ATP

What is the role of the:
Nucleus

- Storage of genetic information of the organism
- Controls metabolism
- Protein synthesis
- Processing of genetic information

What is the role of the:
Nucleolus

Where ribosomal subunits are produced

What is the role of the:
Nuclear pore

Semi-permeable spaces allowing for substances to pass between nucleus and cytoplasm.
Larger substances are permitted to pass through.

What is the role of the:
Rough endoplasmic reticulum

Has ribosomes attached.
Close to the nucleus and some other organelles.
Enzymes break down things like cellular debris.

What is the role of the:
Smooth endoplasmic reticulum

No ribosomes attached.
Synthesis of steroids and other substances.

What is the role of the:
Golgi apparatus

Contains and packages vesicles (proteins, lipids, ...)

What is the role of the:
Mitochondrion

ATP production

What is the role of the:
Ribosome

Protein synthesis within a cell, or secreted by exocytosis to the rest of the body.
If a ribosome is attached, it will be released to use elsewhere in the body. If a ribosome is free, it will be used by the cytosol itself.

What is the role of the:
Lysosome

Contains enzymes, meaning that it detoxifies.

What is the role of the:
Plasma membrane

Controls entry and exit of materials to and from the cell. Also helps maintain the cell's shape.

What is the role of the:
Nuclear membrane

Controls what enters and exits the nucleus

What is the role of the:
Centrosome

This is the region where centrioles are created

What are centrioles?

They organize microtubules which in turn organize spindle fibers for cellular division

Which organelles are not membrane-bound?

Ribosomes, centrioles

Which organelle is the most abundant in:
Cells in the testes and ovary that make steroid hormones (lipids)?
(a) Smooth endoplasmic reticulum
(b) Rough endoplasmic reticulum
(c) Mitochondria

(a) Smooth endoplasmic reticulum

Which organelle is the most abundant in:
A muscle cell that exhibits a high rate of metabolic memory?
(a) Golgi apparatus
(b) Centriole
(c) Mitochondrion

(c) Mitochondrion

Which organelle is the most abundant in:
A liver cell that detoxifies blood?
(a) Rough endoplasmic reticulum
(b) Lysosome
(c) Ribosome

(b) Lysosome

Which organelle is the most abundant in:
An endocrine cell that synthesizes and secretes a protein-based hormone?
(a) Golgi apparatus
(b) Lysosome
(c) Centriole

(a) Golgi apparatus