Chapter 3: Genetics: Reproducing Life and Producing Variation

Question 1

Topic Question

Answer 1

What is the genetic code?
What does the genetic code (DNA) do?
How does understanding genes help us understand variation?

Question 2

Tree of Life Diversity

Answer 2

Bacteria- largest diversity
Archaeo- ancient diversity
Metazoans (middle-life)- humans

Question 3

Eukaryotic Cell

Answer 3

Metazoan cell with membrane bound organelles, nucleus
The “true nuts” (nucleus), 1.2 billion years old
Single celled organism and multi-celled
DNA controlled in membrane-bound nucleus
Mitochondria a prokaryote (endosymbiosis) have their own DNA and is a Alpha protea bacteria

Question 4

Prokaryotic Cells

Answer 4

DNA distributed throughout cell, with lipid bi-layers

Question 5

Somatic Cells

Answer 5

cells part of a larger body of multi-cellular organisms like neurons, blood cells, plant cells, have full DNA

Question 6

Chloroplast

Answer 6

a cyanobacteria

Question 7

Gamete

Answer 7

23, restore meiosis with egg and sperm

Question 8

Chromosomes

Answer 8

linear molecules of DNA, found in nuclei “nuclear DNA”

Question 9

Mitochondrion

Answer 9

have their own DNA which is circular

Question 10

DNA Structure

Answer 10

Double Helix, a phosphate, 5 carbon sugars, nitrogen, these are nucleotides (building blocks)

Question 11

Genome

Answer 11

complete set of genetic information for an organism

Question 12

homoplasmic

Answer 12

all cells have same set of DNA, except red blood cells

Question 13

heteroplasmic

Answer 13

not same in every cell

Question 14

Matrineal v. Patrineal

Answer 14

traces DNA in mitochondria from dad or mom, use Y to trace ancestry

Question 15

paleogenetics

Answer 15

ancient genetics

Question 16

polymerase chain reaction

Answer 16

copies are made through heating and cooling

Question 17

Nucleotide bases

Answer 17

A adenine
T Thymine
G guanine
C cytosine

Question 18

Nucleotide paring

Answer 18

AT, GC

Question 19

DNA Replication

Answer 19

DNA unravels, enzymes come along to make complimentary stands (free floating nucleotides)
For every 1000 base pairs, there is at least one mistake

Question 20

Replication

Answer 20

copying DNA prior to cell division, so each daughter cell receives full complement of DNA

Question 21

Mitosis

Answer 21

cellular and nuclear division to make 2 identical diploid daughter cells 2n to 2n

Question 22

Meiosis

Answer 22

2 stage cell/nuclear division to make haploid gametes, egg and sperm 2n to n (sex cells don’t receive full complement

Question 23

Chromosome Types

Answer 23

Homologous Pairs (same descent)
Autosomes (22 pairs)
Sex chromosomes (1 pair) x and y
Karyotype: set of all chromosomes

Question 24

Prenatal Development

Answer 24

Haploid: egg and sperm meet, sperm 1n and egg 1n create diploid zygote 2n
Zygote is fertilized egg of 2n and continues to divide through meiosis to make more gametes

Question 25

Meiosis II

Answer 25

division without replications from 2n to 1n (reduction division) = sex cells

Question 26

Law of Independent Assortment

Answer 26

mendelian’s peas and punnet square.

occurs when 2 chromosomes flip or exchange arms called crossing over

Question 27

Recombination

Answer 27

via crossing over is independent assortment, exchange of genetic material

Question 28

Translocations and nondisjunctions

Answer 28

Trisomy- 3 chromosomes together = Down’s Syndrom

Monosomy- 1 chromosome left alone = non fertile

Question 29

Crossing Over

Answer 29

homologues align, wrap, and exchange pieces

Question 30

Haplotypes

Answer 30

group of alleles often inherited together like blue yes and blonde hair

Question 31

Haplogroups

Answer 31

large sets of haplotypes

Question 32

Linkage

Answer 32

Close gene proximity = departure from independence (law of not quite independent assortment)

Question 33

Enzymes

Answer 33

catalyze chemical reactions (lactase)

Question 34

Structural Proteins

Answer 34

give structure and support to tissues (keratin)

Question 35

Gas transport proteins

Answer 35

Carry vital gases to tissues (hemoglobin)

Question 36

Antibodies

Answer 36

Part of immune system

Question 37

Hormones

Answer 37

regulate metabolism (insulin)

Question 38

Mechanical Proteins

Answer 38

specific work functions (actin-muscle contraction)

Question 39

Nutrients

Answer 39

Provide vital nutrients to tissues (ovalburim)

Question 40

Transcription

Answer 40

DNA transcribed into mRNA in the nucleus of the cell

Question 41

Translation

Answer 41

mRNA translated into amino acid chain (polypeptide) at the ribosomes (proteins phenotype, nucleic acid genotype)

Question 42

Marfan syndrome

Answer 42

uncontrolled bone growth (Lincoln)

Question 43

Regulatory Genes

Answer 43

On/Off like Chicken teeth, lactose intolerance and Marfan syndrome

Question 44

Homeotic Genes

Answer 44

Hox Genes are regulatory genes that appear in a row of DNA in clusters, from upstream to downstream
As they appear they regulate the formation of body parts from head (anterior) to tale (posterior)
Hox genes specify positional identity within an embryo of what kind of body part will develop

Question 45

Simple dominance

Answer 45

dominant trait R over little r

Question 46

Codominance

Answer 46

both alleles are equally dominant and are fully expressed, intermediate pink between red and white allelesl

Question 47

Blood pheno and genotypes

Answer 47

A - AO, AA
B - BO, BB
AB - AB
O - OO

Question 48

Polygenic traits

Answer 48

Many genes contribute to single effect like height, skin color, eye color

Question 49

Pleiotropic

Answer 49

One gene has multiple biological effects like sickle cell

Question 50

Epigenetics

Answer 50

heritable effects on gene expression due to smoking, alcohol, obesity, physical activity, cancer/disease

Question 51

Heritability

Answer 51

H^2= genetic variation / (gene variation + environmental variation)