ATI TEAS 7 BIOLOGY

Cells and their organelles

• Plasma membrane- Phospholipid bilayer embedded with proteins

• Cytoplasm- Semifluid substance present inside the membrane, has organelles

• Nucleus- Most prominent organelle. Spherical, protected by double membrane, contains genetic information in the form of nucleic acid DN

-DNA encodes for all necessary proteins of the cell, in turn the organism can carry out its life functions

Organelles- Carry out the cells metabolic life functions

Ribosomes

Site of protein synthesis

endoplasmic reticulum

Smooth- No ribosomes, Lipid production and storage

Rough- Makes proteins in ribosomes

Golgi aparatus

Proteins sent in vesicles go here

• Then fuse with golgi to be transported where the proteins are needed

Also does this with digestive enzymes

Mitochondria

Organelle that changes food energy into useable cellular energy via cellular respiration

Mitosis

Meiosis

Tissue

Biological organization

Cells ^» Tissues » Organs »Organ Systems »Organism

Macromolecules

Polymers built by linking monomers (small subunits)

3 classes made of specific monomers

• Covalent bond by removing ATP

• Dehydration reaction

1. Polysaccharides- Monosaccarides (sugars in the form of carbohydrates)

2. Proteins- (Amino acids)

3. Nucleic acids- (Nucleotides)

Macromolecule functions

Dependent on shape

1. Polysaccharides

• Crabohydrates

• Major food group, gives energy

• Glycogen into glucose used by cells to make ATP. Hydrolysis reaction (opposite of dehydation reaction)

• Chitin and cellulose provide skeleton support

2. Proteins

• All composed of 20 amino acids

• Polypeptide that folds into a 3 dimensional shape

• Process^ driven by hundreds of noncovalent (hydrogen) & covalent (sulfur-sulfur) bonds

• * Hemoglobin is made of 4 separate polypeptide chains that each fold up spontaneously

• Creates chemical reactions through enzymes

3. Nucleic acids

• DNA & RNA

• DNA- 2 nucleic acid polymers to make double helix

-Stores geentic info in cells

• RNA- Type of nucleotide (ribonucleotide) made up of a ribose sugar linked on one side of a trio of phosphates & on the other side to a nitrogenous base

-Converts information stored in DNA to proteins

4. Lipids

• Insoluable in water- Cholesterol, steroids, fats, fatty acids, & phospholipids

• Diverse set of molecules that group together bc of how they interact in water

• Hydrophobic, don’t disssolve in water, bc that are mostlu carbon-carbon or carbon-hydrogen bonds

• Phospholipids form cell membrane

• Tryglycerides concentrated energy storage for the body

• Steroids include cholesterol & hormones: testosterone and estrogen

• Phospholipids & triglycerides made of fatty acids (hydrocarbon chains with a carboxylic acid on one end) & glycerol (type of sugar)

Atom

Basic unit of matter

• Undergo chemical reactions by gaining or losing electrons

• Atoms property can be inferred by its postion on the periodic table

• Position is based on valence electrons in its outermost shell

• Can gain, lose, or share electrons to make diff. chemical bonds

Elements

Indicated on periodic table by its number of protons, valence shell configuratuon, and chemical/physical properties

Elements that make up majority of living organisms

• Carbon

• Hydrogen

• Oxygen

• Nitrogen

Fundamental particles

Protons- +

Neutron- no charge

Electron- -

Atomic structure

Protons and neutrons make up nucleus

Electrons on shell

Atomic mass

Protons + neutrons

Atomic number

Protons in an element

protons = neutrons

Isotopes

Versions of the same elements with diff numbers of neutrons are isotopes of each other

EX.

Carbon-12: 6 protons & 6 neutrons

Carbon-14: 6 protons & 8 neutrons

Chemical bonds

States of matter

Liquid- No definite shape, definite volume

Solid- Definite shape and volume

Gas- No definite shape or volume

Plasma- No definite shape or volume, conducts electricity

• Found in lightning, stars, neon

Density

ratio of mass to volume

Density = Mass/Volume

Heat and temperature

Have absolute zero

• 0 kelvin = -273 deg celcius

• Molecules are constantly moving

Temperature

• Measures the average energy & motion of molecules

• Measured in kelvin. fehrenheit, celcius

• Describs how hot or cold a substance is

Heat

• Measured in calories or joules

• Form of energy added to or produced by a substance or system

Phase change

Adding heat does not always increase temperature

• Phase change: added heat may be used to change the state of matter instead

Specific heat capacity

Amount of energy needed to raise the temperature of 1 gram of substance by 1 degree celcius

• Diff substances require diff amounts of energy to change temperature

Phase changes

1. Melting- Solid to liquid

2. Freezing- Liquid to solid

3. Vaporization/evaporation- Liquid to gas

4. Condensation- Gas to liquid

5. Sublimation- Solid to gas

6. Deposition- Gas to solid