1110 Unit 1 Exam review

All living things must be made of one or more cells. What feature makes a cell a cell?

• Cell membrane

• Cell wall

• Protein coat

• DNA containing nucleus

Answer explanation

The cell membrane is also known as the phospholipid bilayer

Tags

NGSS.MS-LS1-1

You find a single celled organism with DNA held in the cytoplasm and no membrane bound organelles. What type of organism is this?

• Prokaryote

• Eukaryote

• Dikaryote

Which subatomic particle has a negative charge?

• Proton
• Neutron
• Electron
• Positron

In a neutral atom, the number of protons equals...

• The number of neutrons

• The number of electrons

• The valence

• The mass

Answer explanation

Unless otherwise stated, the number of protons will = the number of electrons.

The mass is the protons + neutrons

The atomic number is the number of protons

Why does ice float?

• Ice is heavier than water
• Ice has a lower density than water
• Ice is transparent
• Ice is solid

Answer explanation

The hydrogen bonds in water become ridged when frozen and create more space between the molecules.

What action will change every level of structure in a protein?

• Breaking H bonds between N and C groups

• Adding an extra glycine amino acid

• Forming new disulfide bonds

• removing all polypeptide subunits

If you see an O in a side chain/ R group...

• It is basic

• It is nonpolar

• It is acidic

• It is polar

Answer explanation

Oxygen is very electronegative

Tags

NGSS.HS-LS1-1

Which is the structural carbohydrate used in both fungi and animals?

• Starch
• Glycogen
• Cellulose
• Chitin

Which are examples of secondary structures?

• a-knots

• B- Pleated sheets

• Hairpin loops

• Disulfide bonds

• B-helix

Answer explanation

In proteins, a-helix and B-pleated sheets

In RNA, Hairpin loops

In DNA, the double helix

Lipids are the best macromolecule for energy storage because...

• It has many strong bonds

• It has many H-C bonds

• It has a bent structure

• Carbs are better

Answer explanation

The weaker the bond the higher the potential energy