Midterm 1 : Biology

Hypothesis

Possible answer to a scientific question. Must be testable and falsifiable.

Principle of Parsimony

If all else is equal, the simplest explanation is the better option than the one with complicated one.

Diagnostic Criteria

allowing us to diagnose something while excluding everything else. must be true for all things in the category.

Deductive vs Inductive logic

Deductive: if all A’s=B’s and all B’s= C’s than all A’s must = C’s

Inductive: If some As are Bs and some Bs are Cs then an A is probably also a C (but it depends)

all cells have same four universal parts. What are they?

1. cell membrane/plasma membrane

2. cytosol/cytoplasm

3. DNA

4. ribosomes

Ionic vs Covalent

Ionic: Transfer of electrons

Covalent: Sharing of electrons

why is water important what would happen without water?

Water is important because it is the main solvent in all living cells and is needed most for chemical reactions without it, cells could not carry out important chemical reactions, transport materials, or maintain their structures so they could not survive.

Polymers

Made of many monomer (Everything is a polymer except lipids)

polymerization

making polymer

depolarization

Breaking apart polymers into monomer

dehydration synthesis

Small molecules joined together to form a polymer and water gets out as a product

hydrolysis

Uses water to break down polymers into monomer

Carbohydrate(What it’s made of and why it’s necessary)

Monosaccharide(Simple sugars like glucose), Main source of energy and storage for all cells.

Lipids(What it’s made of and why it’s necessary)

glycerol and fatty acids, Store, long-term energy, maintain bodies, heat, and form cell membrane

nucleic acid (What it’s made of and why it’s necessary)

nucleotides, Stores and transmits genetic information and contains instructions to make proteins

1 gene

specific region of DNA that contains destructions to build at least one functional molecule

Proteins(What it’s made of and why it’s necessary)

Amino acid, Build and repair tissues and act as enzymes to speed up chemical reaction reactions

what are the four possible levels of protein Structure

Primary: Order of amino acids dictated by the nucleotide sequence

Second: Initial folding

Tertiary: Interactions between regions cause more folding into 3-D shape

Quaternary: Some: Multiple polypeptides that bond together

types of protein and what they do

1. enzymes: Biological Catalyst: Increases reaction rate without being used up

2. Transport: Assist movement of particles and/out of cells

3. Receptor: Detect stimuli and initiates cell response

denaturation

Complete loss of protein shape, permanent, and a irreversible, therefore losing all its function

Bacteria

Circular chromosomes usually one maybe additional smaller ones ( plasmids)

only bacteria has peptidoglycan cell well

Square cube law

As the size of an object increases, the volume increases faster than its surface area, causing its surface area : volume ratio decrease

Gram positive

• thick Peptidoglycan layer

• No outer membrane

gram-negative

• thin peptidoglycan layer

• extra outer membrane

prokaryotic

• No Nucleus

• Bacteria in Archea

eukaryotic

• Has nucleus

• Plant animals, fungi, and protists

Archea ( no nucleus)

• Prokaryotic, but more closely related to eucaryotic than to bacteria

• No peptidoglycan cell walls

extra cellular Metrix

Network of cell products anchored to the external surface of the cell

cytoskeleton

Internal framework of proteins

• Cell shape

• Internal support for self structure

• Cell movement

ribosomes

Molecular machine made of rRNA + proteins

RNA → proteins ( translated by ribosomes)

in eukaryotic, but not in prokaryotic cells

Membrane bound, organelles

• Mitochondria

• Nucleus

• Endo membrane system

symbiosis (types of it)

Long-standing co-evolutionary relationship between two or more species.

• Mutualism: Both partners benefit

• Commensalism: One benefits and one is unbothered

• Parasitism: One benefit benefits, and one is harmed

Endosymbiosis hypothesis

One partner lives inside the other one, and instead of destroying the inside cell, they work together. overtime it becomes a permanent part of the cell and helps it

anabolic reactions

Build large molecules out of smaller ones (Most cost Energy)

catabolic reactions

Breaks down large molecules to smaller Ones (Most release energy)

endocytosis vs exocytosis

Endocytosis: Imports

Exocytosis: Exports

nucleus

houses and protects DNA

rough ER

makes Protein(Protein synthesis)

Golgi apparatus

receives, finishes, and ships out cell products

smooth ER

lipid production