A&P - Chapter 3 (Part 2) Flashcards
What are the type of chemical bonds? (3)
- Ionic
- Covalent
- Hydrogen bonds
When do you know if an atom is chemically stable?
When the outer shell is full
When is an atom unlikely to bond? Why?
When it is stable because it has no electrons it wants to give away
Ionic bonds
Form between an atom that only has 1 or 2 electrons in its outermost energy level
- donates electrons
Ion
Atom or group of atoms with an electrical charge
- either positive or negative
When do ions form?
They form when an atom gains or loses electrons in its outer energy level to become stable
Positive ions
Has lost electrons
- Eg) Na+, Ca+
Negative ions
Has gained electrons
- Eg) Cl-
When do ionic bonds form?
When positive and negative ions attract each other due to an electrical attraction
When do covalent bonds form?
When atoms fill their energy levels by sharing electrons to become stable
How do covalent bonds share electrons?
They must stay close to each other
Do bonds break easily in covalent bonds? Why?
No because they are so close together
- they are strong
Where would you find hydrogen bonds?
Between molecules
What is the weakest type of chemical bond?
Hydrogen bonds
What do hydrogen bonds result from?
Unequal charge distribution on molecules
- unequally shared
What is an example of a hydrogen bond?
Water molecules
How are hydrogen bonds formed?
Areas of different partial charges attract one another
What are chemical reactions involved with?
The formation or breaking of chemical bonds
What are 3 types of chemical reactions involved in physiology?
- Synthesis reaction
- Decomposition reaction
- Exchange reaction
Synthesis reaction
Combining of two or more substances to form a more complex substance
- eg) A + B –> AB
Decomposition reaction
Breaking down of a substance into two or more simpler substances
- eg) AB –> A + B
Exchange reaction
Decomposition of two substances and in exchange, synthesis to two new compounds come from them
- eg) AB + CD –> AD +CB
Irreversible reactions
Reactions that are unable to occur in both directions
What do chemical reactions always involve?
Energy transfers
Where is some of the energy stored in chemical reactions?
In the bonds and are released when the bonds are broken
Metabolism
All of the chemical reactions that occur in body cells
What makes up metabolism? (2)
- Catabolism
2. Anabolism
Catabolism
Chemical reactions that break down complex compounds into simpler ones and release energy
What is an example of catabolism?
Hydrolysis
What are the end products of catabolism? (3)
- Carbon dioxide
- Oxygen
- Other waste products
Anabolism
Chemical reactions that join simple molecules together to form more complex molcules
What is an example of anabolism?
Dehydration synthesis
- condensation
