Lecture 2, Life Processes 2 Flashcards
What are the 6 structural organizations of the body?
Chemical level → Cellular level → Tissue level → Organ level → Organ system level → Organism level
When are ionic bonds formed?
Reactive atoms that are missing or have an excess of electrons in their outer shell.
Why do so many things dissolve in water?
Water is a polar molecule (oxygen side slightly negative, hydrogen side slightly positive), strong attraction between water and other molecules disrupts bonds between other molecules such as NaCl.
What is an electrolyte?
Any molecule that creates an electrically conducting solution when dissolved in water, e.g. NaCl (salt), dissolves in water, allowing Na+ and Cl to participate in electrical signaling.
Why is oil ‘non-polar’?
It can’t break bonds between water molecules.
What are the three properties of a hydrophilic molecule?
‘Water-loving’, dissolves in water, polar molecules e.g. sugar, protein, most hormones, and electrolytes.
What are the three properties of hydrophobic molecules?
‘Water-hating’, dissolves in oil, non-polar molecules e.g. oils and fats, cholesterol, some hormones.
Every cell membrane is made of what?
A double layer of phospholipids- Hydrophilic exterior and hydrophobic interior.
What are the three macromolecules and give an example of what they are broken down to?
Carbohydrates (glucose and other monosaccharides), lipids (fatty acids and glycerol), and proteins (amino acids and polypeptides).
What is ATP and what is it used for?
A molecule that cells use as energy for most cellular processes.
Cellular transport is the process of substances entering or exiting the cell, what is passive and active transport?
Passive requires no energy, active requires energy.
What is endocytosis and exocytosis?
Endocytosis is when the cell membrane deforms to engulf (‘eat’) a substance. Exocytosis is when a cell membrane deforms to release a substance.
What is diffusion?
The movement of particles down a gradient because particles are always moving (except at absolute zero). Particles moving down a concentration gradient move from a higher concentration to a lower concentration.
What is an electrical gradient?
Charged particles move towards the opposite charge- ‘opposites attract’.
Water also diffuses down a concentration gradient from a high concentration to a low concentration, why is this?
Solutes attract water, water moves to where there are more solutes (less water concentration).
What are the three ‘tonic’ names used to describe the impermeable solutes in a solution surrounding cells and what do they mean?
Hypo (less), Iso (same), Hyper (more).
Why does active transport require ATP to move substances?
Because it moves them against their concentration and electrical gradients.
What does an ATPase pump do?
Moves sodium (3Na+) out of the cell and potassium (2K+) into the cell each pump cycle
