Biological Basis Of Disease I

Front 1

Define Amphipathic

Back 1

Containing both hydrophilic (water-loving) and hydrophobic (water-hating) parts.

Front 2

What is cell membrane made of?

Back 2

Lipid bi-layer and protein channels

Front 3

Define ATP

Back 3

Adenosine 5-triphosphate. This is a cell's major energy carrier.

Front 4

Define ligand

Back 4

A molecule that exclusively interacts with (or binds to) specific sites on proteins.

Front 5

Define Life

Back 5

Living things reproduce, metabolize (to maintain homeostasis), are made of cell(s), and respond to environmental stimuli.

Viruses are a possible exception.

Front 6

Determinants of health

Back 6

Health is determined by one's behavior, environment, genes, and social context.

Front 7

Levels of organization in animals

Back 7

cells --> tissues --> organs --> organ systems --> organism

Front 8

What are the chemical building blocks of cells?

Back 8

Fatty acids (make lipids), amino acids (make protein), carbohydrates (make energy), and nucleic acids (make RNA and DNA)

Front 9

What are enzymes?

Back 9

Enzymes are proteins that catalyze chemical reactions.

Front 10

How are prokaryotic cells different from eukaryotic cells?

Back 10

Prokaryotes lack organelles.

Front 11

Define organelles

Back 11

Membrane-bound cell parts with specialized functions.

Front 12

Characteristics of nucleus

Back 12

Found in Eukaryotic cells only.
Stains easily.
Surrounded by nuclear envelope (double membrane).
Contains DNA (chromosomes).

Front 13

Characteristics of DNA

Back 13

DNA must copy itself before cell can reproduce.
Is the site of transcription (RNA synthesis or gene expression)

Front 14

What is the role of mitochondria?

Back 14

Mitochondria produce ATP

Front 15

What is the role of lysosomes?

Back 15

Lysosomes break macromolecules down into sugar and acids (nucleic, fatty, amino). They contain hydrolytic enzymes and are part of the endocytic pathyway.

Front 16

What is mucosa?

Back 16

A tissue composed of epithelial, muscle, and other cell layers that serves as a barrier against infection. Mucosae line the intestines, various orifices.

Front 17

How do cells communicate with each other?

Back 17

Through chemicals, hormones. Different cells can respond differently to same chemical.

Front 18

Describe hormone transmission

Back 18

Protein-based hormones get in/out of cell through specialized proteins embedded in cell membrane. Lipid-based steroids (and thyroid hormones) bind to receptors on inside of membrane.

Front 19

What is the central dogma of protein synthesis?

Back 19

Transcription (DNA --> RNA)
Processing (RNA --> mRNA)
Translation (mRNA --> protein)
Replication (copies of DNA)

Front 20

List 5 nucleotides (nucleic acid polymers)

Back 20

Adenine
Cytosine
Guanine
Thymine
Uracil

Front 21

Describe DNA structure

Back 21

A phosphate group bound to ribose (sugar) bound to nucleotide base (A, T, C, G). Single strand is polar: one end is 5'-PO₄ and other is 3'-OH. Binding strand will complement this polarity.

Front 22

Difference between RNA and DNA

Back 22

RNA uses Uracil instead of Thymine and has an extra hydroxil group (OH). DNA is "deoxy" because it lacks this OH.

Front 23

What separates the double helix for transcription?

Back 23

DNA polymerase

Front 24

Describe chromosomes

Back 24

Made of bundled-up DNA. Each chromatid is a copy of the other. Sister chromatids are joined at the "centromere".

Front 25

Define chromatid

Back 25

Chromatid is one half of a chromosome (ie, one half of the "X")

Front 26

List the steps of cellular mitosis (asexual, somatic reproduction)

Back 26

1. DNA synthesis
2. Chromosomal duplication
3. Chromatid separation
4. Cytokinesis (cell division)

Front 27

List the steps of cellular meiosis (sexual reproduction)

Back 27

(Pre-requisite: oogenesis, spermatogensis)
1. Meosis 1
---DNA replication yields 2 chromosomes
---Chromosomes separate
2. Mesosis 2
---no DNA replication
---Chromatids separate
3. Fertilization
---Chromatids from two parents join into genetically unique chromosomes

Front 28

How many chromosome do humans have?

Back 28

22 pairs

Front 29

Define allele

Back 29

Different sequences for genes

Front 30

Define homozygous

Back 30

Same allele on both chromosomes

Front 31

Define heterozygous

Back 31

Different allele on each chromosome

Front 32

Define dominant-recessive inheritance

Back 32

dominant allele 'masks' recessive allele

Front 33

Define co-dominant inheritance

Back 33

shared expression of traits (eg, AB blood type)

Front 34

Define incomplete dominant inheritance

Back 34

phenotype between dominant and recessive traits

Front 35

Define polygenic inheritance

Back 35

several genes influence trait (often continuous variation)

Front 36

Define pleiotrophic inheritance

Back 36

single gene affecting several traits

Front 37

Describe RNA processing

Back 37

Add caps and tails to strand.
Introns (non-coding sequences) removed.
Voila -- mRNA.

Front 38

What regulates gene expression?

Back 38

Proteins. They bind to certain regions on DNA and promote or inhibit expression (RNA transcription) of that gene sequence.

Front 39

Define mRNA translation

Back 39

Nucleotide sequence is translated into amino acid sequence. Proteins are polymers of amino acids.

Front 40

Define codon

Back 40

A sequence of 3 nucleotides; each codon represents one amino acid.

Front 41

Start codon

Back 41

AUG = methionine

Front 42

Stop codons

Back 42

UAA, UAG, UGA

Front 43

What is tRNA?

Back 43

"transfer" RNA decodes nucleotides into amino acids. This takes place in ribosomes.

Front 44

What is rRNA?

Back 44

"ribosomal" RNA is a complex of proteins / amino acids and RNA

Front 45

List 2 types of polymorphism in RNA translation

Back 45

1. single nucleotide polymorphism (point mutation) yields single wrong codon
2. frame shift mutation = added or deleted nucleotide results in ALL subsequent codons being wrong!

Front 46

Define protein

Back 46

A macromolecule made of folded polypeptides.

Front 47

What are the parts of an amino acid?

Back 47

End 1: Amino group (NH₃)
Middle: C-H group
End 2: Carboxyl acid group
Everything else: "R" group

Front 48

How many amino acids do humans need?

Back 48

20. We produce 11 in-house. The other 9 must be consumed.

Front 49

What is a polypeptide?

Back 49

A single string of 3 to 100 amino acids. If longer than 100, we just call it a protein.

Front 50

List the 4 levels of protein structure

Back 50

--Primary: amino acid sequence
--Secondary: spatial orientation of amino acid chain
--Tertiary: folding of amino acid chains
--Quaternary: number and relationship of polypeptides

Front 51

Define denaturation

Back 51

Permanent disruption of protein structure resulting in loss of biological function.