Life Processes Flashcards
What are the 6 levels of organisation in the body?
- Organism level
- Organ system level
- Organ level
- Tissue level
- Cellular level
- Chemical level
What are organs made of?
Multiple types of tissues
Example: skin
What are the 4 basic tissues?
Epithelial - lines surfaces
Connective - structural support
Muscle tissue - contracts
Nervous tissue - conducts electricity
What are tissues made of?
Each type of tissue is made up of cells which determines the function
What are cells?
The smallest living units that carry out all vital physiological functions
What is an element?
A pure substance. Can exist as a single atom or molecule made of the same type of atom
What is an atom?
The smallest particle of an element
What are molecules?
Made of two or more atoms either:
- Of the same element eg. 2 hydrogen OR
- As a compound eg. 2 hydrogen + 1 oxygen
What are the 4 most common elements in the body?
- Oxygen (65%)
- Carbon (18%)
- Hydrogen (10%)
- Nitrogen (3%)
What percentage of solids are in the body?
40-45%
What percentage of fluids is in the body?
55-60%
What is the total body water (TBW)?
All water within and outside of all the cells of the body
What percentage of the TBW is intracellular fluid (ICF)?
66% (2/3)
What percentage of the TBW is extracellular fluid (ECF)
33% (1/3)
What are the two divisions of ECF?
80% interstitial fluid
20% blood plasma
Do bodies with more fat have lower or higher TBW?
Bodies with more fat have lower TBW (~55% or less)
Bodies with more muscle have higher TBW (~60%)
What are atoms composed of?
Protons, Neutrons and Electrons
How many electrons can the inner shell of an atom hold?
Max 2
How many electrons can the outer shell of an atom hold?
max 8
What is a reactive atom?
When the outer shell isn’t full
What is a cation?
A positively charged ion.
The atom needs to give away an electron to become stable. Therefore it loses an electron, making it more positive.
What is an anion?
A negatively charged ion.
The atom needs to receive an electron to become stable. There it gains an electron and becomes more negative.
What is an Ionic Bond?
Electron Exchange. An electrostatic attraction between two atoms where one atom gives an electron to the other. Eg. NaCl
What is a covalent bond?
Electron Sharing. Eg. A water molecule is created when 2 hydrogen atoms and 1 oxygen atom share electrons.