Note Cards For Bio Exam 3

Front 1

Blending Model of Inheritance

Back 1

All traits of parents are blended in their offspring.

Front 2

What are the two problems with Blending Inheritance Model?

Back 2

- All individuals in a population will eventually look alike.
- Same traits skip a generation and appear in the next, unblended.

Front 3

Gregor Mendel

Back 3

- Austrian Monk
- Father of modern genetics

Front 4

Particulate Model of Inheritance

Back 4

Parents pass distinct particles (alleles) to their offspring that do not blend with other articles.

Front 5

Diploid

Back 5

Two copies of every chromosome/gene.

Front 6

Homologous Chromosomes

Back 6

A pair of the same chromosomes, one copy from each parent.

Front 7

Haploid

Back 7

One copy of every chromosome. Half the number you need.

Front 8

Gametes

Back 8

Name for haploid eggs and sperm.

Front 9

Why are gametes haploid?

Back 9

If they were not, chromosome number would double each generation.

Front 10

Gene

Back 10

Piece of DNA that codes for a protein.

Front 11

Alleles

Back 11

Different forms of the same gene.

Front 12

Phenotype

Back 12

Physical description of an organism's traits.

Front 13

Genotype

Back 13

Describe which alleles are present.

Front 14

Homozygous

Back 14

Two copies of the same allele (LL or ll). Can be dominant or recessive.

Front 15

Heterozygous

Back 15

Two different alleles (Aa or Bb).

Front 16

Dominant

Back 16

One allele hides the appearance (phenotype) of another.

Front 17

Recessive

Back 17

Name for the hidden allele.

Front 18

With Dominance, genotypes can be...

Back 18

- L is dominant to l
- LL = Homozygous dominant
- Ll = Heterozygous
- ll = Homozygous recessive

Front 19

Incomplete dominance

Back 19

Phenotype of heterozygote is intermediate between phenotype of two homozygous genotypes (ex. Red and white make pink flowers).

Front 20

Co-dominance

Back 20

Phenotype of heterozygote simultaneously shows both phenotypes (Ex. You can have AA and be A blood type, you can have BB and be B blood type or you can have AB genotype and be AB blood type which is both fully A and B, not intermediate between AA and BB).

Front 21

Multiple alleles

Back 21

Two or more alleles for a gene. (Ex: the ABO blood group).

Front 22

Epistatsis

Back 22

One gene affects the phenotypic expression of another gene. Ex: mouse fur color. Influences fur color in other mammals too, like Labrador Retrievers.

Front 23

Pleiotropy

Back 23

one gene with multiple effects on the phenotype. Cystic Fibrosis because the mutated gene affects the airways, pancreas, sweat glands, and reproductive ducts, etc.

Front 24

Polygonic test

Back 24

one phenotypic trait is controlled by many genes.

Front 25

How can you tell if a trait is polygenic?

Back 25

The phenotypes of a polygenic trait form a normal distribution (bell-shaped curve)

Front 26

Mendel’s Two Laws of Inheritance:

Back 26

- Principle of Segregation of alleles
- Principle of independent assortment

Front 27

Principle of Segregation of alleles

Back 27

sexually reproducing, diploid individuals have two copies (alleles) for each gene and these alleles separate from each other such that each egg or sperm gets only one allele.

Front 28

Principle of independent assortment

Back 28

alleles of one gene assort independently of the alleles at another gene.

Front 29

Sex-specific inheritance patterns

Back 29

23 pairs of chromosomes

Front 30

Autosomes

Back 30

Chromosomes not involved in sex determination (22 pairs)

Front 31

Sex chromosomes

Back 31

chromosomes that are involved in sex determination (1 pair)

Front 32

Sex linked traits

Back 32

genes found on sex chromosomes and show sex-specific patterns of inheritance

Front 33

Why are sex-linked traits important?

Back 33

Because the phenotypes will be seen more often in males than in females. Females can be carriers

Front 34

Dosage compensation

Back 34

genetic mechanisms that equalize the expression of X-linked genes in males and females

Front 35

Why?

Back 35

Because females are XX, males are XY

Front 36

X-chromosome Inactivation

Back 36

one female X chromosomes shuts off, leaving one working copy, like males. Happens in all placental mammals.

Front 37

How does a Female Calico Cat get her patterned fur color?

Back 37

- Fur color is X-linked
- Black allele, orange allele
- Different cell lineages shut off different X chromosomes

Front 38

Phenotypic plasticity

Back 38

the ability of an organism with a given genotype to change its phenotype in response to changes in the environment.

Front 39

Examples in Humans

Back 39

- Musculature
- Skin tone
- Weight

Front 40

DNA Structure

Back 40

- DNA is a linear molecule (chain-like)
- DNA consists of 4 types of nucleotides (A, G, C, T)
- In any molecule of DNA, A = T and G = C
- DNA is made of 2 strands
- DNA has a net negative charge

Front 41

What are the three main parts of the Nucleotide Chain?

Back 41

- Phosphate group
- Deoxyribose sugar
- Four different bases A, G, C, or T (A = T, G = C)

Front 42

DNA

Back 42

- Deoxyribose sugar
- A, G, C, or T (A = T, G = C)
- Double stranded

Front 43

RNA

Back 43

- Ribose sugar
- A, G, C, or U (A = U, G = C)
- Single-stranded

Front 44

What type of molecular bond holds the two nucleotide chains of DNA together?

Back 44

Hydrogen bonds hold the two nucleotide chains together: A <-- 2 H bonds --> T, G <-- 3 H bonds --> C

Front 45

DNA Replication

Back 45

DNA packed tightly into visible chromosomes only during cell division

Front 46

a.) strand separation

Back 46

DNA strands are unzipped by enzyme helicase

Front 47

b.) Complementary base pairing

Back 47

A, G, C, T bases find their complements

Front 48

c.) Polymerization

Back 48

enzyme DNA polymerase attacks new bases and re-zips new strands

Front 49

Semi-conservative replication

Back 49

each new DNA molecule consists of one new strand and one old strand

Front 50

What is needed to start adding new bases to the nucleotide chain?

Back 50

RNA Primer: short piece of RNA that allows DNA polymerase to work. Later removed by an RNAse enzyme.

Front 51

Mutations

Back 51

- Are rare because DNA polymerase can correct mistakes
- Only one in a billion nucleotides mutates
- Most mutations are bad or have very little or no effect
- Beneficial mutations are rare

Front 52

What are the five most common type of DNA mutations?

Back 52

- Point mutations: TTAGT --> ATAGT
- Deletions: TTAGT --> AGT
- Insertions: TTAGT --> TTGGAGT
- Duplications: TTAGT --> TTAGTTTAGT
- Inversions: TTAGT --> TGATT

Front 53

What are restriction enzymes?

Back 53

Enzymes derived from bacteria that cut DNA at specific sequences where the sequence is the same (palindrome) on both strands of DNA (Example: GG CC, CC GG).

Front 54

Why do some bacteria make restriction enzymes anyway?

Back 54

They use these enzymes to destroy viral DNA that invades them

Front 55

What is the Central Dogma?

Back 55

That the flow of genetic information is from DNA to RNA to protein

Front 56

a.) strand separation

Back 56

DNA strands are unzipped by enzyme helicase

Front 57

b.) Complementary base pairing

Back 57

A, G, C, T bases find their complements

Front 58

c.) Polymerization

Back 58

enzyme DNA polymerase attacks new bases and re-zips new strands

Front 59

Semi-conservative replication

Back 59

each new DNA molecule consists of one new strand and one old strand

Front 60

What is needed to start adding new bases to the nucleotide chain?

Back 60

RNA Primer: short piece of RNA that allows DNA polymerase to work. Later removed by an RNAse enzyme.

Front 61

Mutations

Back 61

- Are rare because DNA polymerase can correct mistakes
- Only one in a billion nucleotides mutates
- Most mutations are bad or have very little or no effect
- Beneficial mutations are rare

Front 62

What are the five most common type of DNA mutations?

Back 62

- Point mutations: TTAGT --> ATAGT
- Deletions: TTAGT --> AGT
- Insertions: TTAGT --> TTGGAGT
- Duplications: TTAGT --> TTAGTTTAGT
- Inversions: TTAGT --> TGATT

Front 63

What are restriction enzymes?

Back 63

Enzymes derived from bacteria that cut DNA at specific sequences where the sequence is the same (palindrome) on both strands of DNA (Example: GG CC, CC GG).

Front 64

Why do some bacteria make restriction enzymes anyway?

Back 64

They use these enzymes to destroy viral DNA that invades them

Front 65

What is the Central Dogma?

Back 65

That the flow of genetic information is from DNA to RNA to protein
- DNA (transcription) --> RNA (translation) --> protein

Front 66

DNA is transcribed into what?

Back 66

An mRNA molecule (messenger RNA)

Front 67

Where does Transcription occur?

Back 67

In the nucleus

Front 68

Does Transcription occur on both strands of the DNA molecule?

Back 68

Transcription occurs on only one strand at a time, but there can be genes on both strands

Front 69

What enzyme makes the messenger RNA (mRNA) molecule?

Back 69

RNA polymerase joins the RNA nucleotides together

Front 70

Where in the cell does Translation occur?

Back 70

Outside the nucleus in the Cytoplasm

Front 71

What is the actual site of Translation?

Back 71

On the ribosome

Front 72

What is a Codon?

Back 72

triplet of mRNA bases (messenger RNA)

Front 73

What does transfer RNA (tRNA) do?

Back 73

Carries amino acids to ribosome to assemble amino acid chain

Front 74

What is an Anticodon?

Back 74

tRNA complement to the mRNA codon

Front 75

What is a protein?

Back 75

Chain of amino acids

Front 76

Why do many DNA mutations have no affect on the phenotype?

Back 76

Because the third codon position can be any nucleotide

Front 77

What is a gene?

Back 77

Piece of DNA that codes for protein with a start and stop codon

Front 78

What does gene expression mean?

Back 78

gene is transcribed and then translated into a protein. Gene goes through transcription and translation

Front 79

Does Transcription require a primer?

Back 79

No, it uses regulatory proteins

Front 80

How are genes Regulated?

Back 80

DNA replication requires primer

Front 81

What are the two main types of Eukaryotic cell division and what are their functions?

Back 81

- Mitosis: to produce more diploid body cells (IPMAT)
- Meiosis: to produce haploid gametes

Front 82

Interphase

Back 82

- Cell growth
- DNA replication

Front 83

What are Sister Chromatids?

Back 83

Chromosome and it’s identical copy

Front 84

What is a Centromere?

Back 84

Protein that holds the sister chromatids together

Front 85

Prophase:
What is a Centriole?

Back 85

Cell organelle that organizes microtubules

Front 86

Prophase:
Microtubules

Back 86

protein filament that moves things inside the cell

Front 87

Metaphase:
What is the metaphase plate?

Back 87

only time you can see chromosomes

A: Imaginary line in center of cell where chromosomes line up

Front 88

Metaphase:
What are Karyotypes?

Back 88

Visual pictures of condensed chromosomes

Front 89

Anaphase:
Kinetochore microtubules attach Centriole to Centromere and _____ chromosomes apart

Back 89

pull

Front 90

Anaphase:
What separates during Anaphase of Mitosis?

Back 90

Sister chromatids

Front 91

Telophase:
Polar microtubules attach Centriole to Centriole and _____ the cell apart

Back 91

push

Front 92

Telophase:
Cytokinesis

Back 92

division of the cell’s cytoplasm

Front 93

Telophase:
How do animal cells divide?

Back 93

Form contractile ring to cut cell in half

Front 94

Telophase:
What is the contractile ring made from?

Back 94

Exact same kind of proteins we have in our muscle: actin

Front 95

Telophase:
What is different about Cytokinesis in plant cells?

Back 95

Plant’s divide from the inside out by depositing cell wall in the middle of cell

Front 96

Telophase:
What are the final products of Mitosis?

Back 96

Genetically identical diploid daughter cells

Front 97

Meiosis (IPMAT):

Back 97

Two parts, Meiosis I and Meiosis II

Front 98

What happens during Meiosis I?

Back 98

cell division and DNA replication

Front 99

What happens during Meiosis II?

Back 99

Another cell division without DNA replication

Front 100

Is there DNA replication during Meiosis II?

Back 100

No

Front 101

What separates during Meiosis II?

Back 101

Sister chromatids

Front 102

How many daughter cells are produced at the end of Meiosis II?

Back 102

4

Front 103

4. Are those cells haploid or diploid?

Back 103

Haploid

Front 104

In human males, how many of the four cells become sperm cells?

Back 104

All of them (4)

Front 105

In human females, how many of the four cells become egg cells?

Back 105

One

Front 106

Why is recombination important?

Back 106

Generates a lot of genetic variation

Front 107

When does Recombination occur?

Back 107

Prophase of Meiosis I

Front 108

Translocation

Back 108

piece of chromosome breaks off but attaches to the wrong chromosome

Front 109

What does radiation do to chromosomes?

Back 109

Breaks chromosomes

Front 110

What is Aneuploidy?

Back 110

Too many or too few chromosomes

Front 111

Down Syndrome

Back 111

caused by setting extra copy of chromosome 21

Front 112

Klinefelter’s Syndrome

Back 112

an XXY (male, XY, inherit extra X) mess up sperm production

Front 113

Trisomy X

Back 113

XXX (in females) extra X but doesn’t affect it, shuts it off

Front 114

Turner’s Syndrome

Back 114

XO, one copy of the X

Front 115

XYY Males

Back 115

inherit double dose of 4 (like XXX female). Tend to be a little tall but no other phenotypical traits.

Front 116

Apoptosis

Back 116

programmed cell death. Is what happens to normal cells that are damaged or not functioning properly. If the immune system doesn’t get them, many cells will kill themselves.

Front 117

Normal Control of Cell Division

Back 117

- One cell sends a signaling molecule to another cell
- Signaling molecule binds to receptor on target cell
- Receptor sends cyclin proteins to nucleus
- Cell divides by Mitosis

Front 118

Some Genes / Proteins involved in the control of cell division:

Back 118

- Cyclins: proteins that build up and when they reach a certain threshold, start mitosis
- MPF (Mitosis-promoting factor): Protein that initiates Mitosis in Eukaryotes

Front 119

Proto-Oncogene

Back 119

genes involved in starting mitosis

Front 120

Oncogene

Back 120

mutated proto-oncogenes that cannot control cell division cancer genes.

Front 121

Tumor Suppressor Genes

Back 121

make proteins that stop cell division and kill cells

Front 122

Oncology

Back 122

study of cancer cells

Front 123

BRCA1 and BRCA2

Back 123

breast cancer genes. Some alleles increase risk in males and females. Also increases risk of prostate and testicular cancers in males.

Front 124

How do cells lose control of cell division?

Back 124

Mutations in the genes that control cell division (mutagens/carcinogens)

Front 125

Tumor (Neoplasm)

Back 125

abnormal growth of tissue. Does not have to be cancerous.

Front 126

Benign Tumor

Back 126

harmless tumors that do not spread to other tissues. Examples: warts, moles

Front 127

Uterine fibroids

Back 127

non-cancerous tumors of uterus. Most common benign tumor in women.

Front 128

Cyst

Back 128

a closed sac with a membrane around it (fluid or air filled)

Front 129

Abscess

Back 129

a collection of pus (dead white blood cells)

Front 130

Cancer (Malignant Tumor)

Back 130

aggressive tumors that divide rapidly and spread to other cells and tissues.

Front 131

Three characteristics of Cancers

Back 131

1.) Cells divide and grow abnormally (mitosis is out of control)
2.) Rely on glycolysis for ATP, all energy devoted to cell division
3.) Metastasis: when cancer cells spread to other parts of the body. Rough cell surface. Cells don’t stick together well. Travel through interstitial fluid to other body parts and form new tumors.

Front 132

What percent of Americans will develop some form of cancer during their lifetime?

Back 132

About 40%

Front 133

Lymphoma

Back 133

a type of cancer that originates in lymphocytes (usually in lymph nodes)

Front 134

Leukemia

Back 134

cancer of the blood cells (usually white blood cells) or bone marrow

Front 135

Benign Tumor

Back 135

harmless tumors that do not spread to other tissues. Examples: warts, moles

Front 136

Uterine fibroids

Back 136

non-cancerous tumors of uterus. Most common benign tumor in women.

Front 137

Cyst

Back 137

a closed sac with a membrane around it (fluid or air filled)

Front 138

Abscess

Back 138

a collection of pus (dead white blood cells)

Front 139

Cancer (Malignant Tumor)

Back 139

aggressive tumors that divide rapidly and spread to other cells and tissues.

Front 140

Three characteristics of Cancers

Back 140

1.) Cells divide and grow abnormally (mitosis is out of control)
2.) Rely on glycolysis for ATP, all energy devoted to cell division
3.) Metastasis: when cancer cells spread to other parts of the body. Rough cell surface. Cells don’t stick together well. Travel through interstitial fluid to other body parts and form new tumors.

Front 141

What percent of Americans will develop some form of cancer during their lifetime?

Back 141

About 40%

Front 142

Lymphoma

Back 142

a type of cancer that originates in lymphocytes (usually in lymph nodes)

Front 143

Leukemia

Back 143

cancer of the blood cells (usually white blood cells) or bone marrow

Front 144

Skin cancer

Back 144

basal cell carcinoma: slow growing and most common type of skin cancer

Front 145

Benign Tumor

Back 145

harmless tumors that do not spread to other tissues. Examples: warts, moles

Front 146

Uterine fibroids

Back 146

non-cancerous tumors of uterus. Most common benign tumor in women.

Front 147

Cyst

Back 147

a closed sac with a membrane around it (fluid or air filled)

Front 148

Abscess

Back 148

a collection of pus (dead white blood cells)

Front 149

Cancer (Malignant Tumor)

Back 149

aggressive tumors that divide rapidly and spread to other cells and tissues.

Front 150

Three characteristics of Cancers

Back 150

1.) Cells divide and grow abnormally (mitosis is out of control)
2.) Rely on glycolysis for ATP, all energy devoted to cell division
3.) Metastasis: when cancer cells spread to other parts of the body. Rough cell surface. Cells don’t stick together well. Travel through interstitial fluid to other body parts and form new tumors.

Front 151

What percent of Americans will develop some form of cancer during their lifetime?

Back 151

About 40%

Front 152

Lymphoma

Back 152

a type of cancer that originates in lymphocytes (usually in lymph nodes)

Front 153

Leukemia

Back 153

cancer of the blood cells (usually white blood cells) or bone marrow

Front 154

Skin cancer: basal cell carcinoma

Back 154

slow growing and most common type of skin cancer

Front 155

Skin cancer: Malignant melanoma

Back 155

an aggressive cancer of melanocytes (skin pigment cells)

Front 156

Lung Cancer

Back 156

very common cancer among men and women. Leading cause is cigarette smoke. About 20% of lung cancer cases are related to 2nd-hand smoke

Front 157

Prostate cancer

Back 157

men only. Nearly all men will develop this if they live long enough. Average age = 70, after 45, regular checkups a good idea

Front 158

Breast cancer

Back 158

most common cancer among women. US women have highest rate in the world (12.5% risk of developing). Small, hard, bumpy-surfaced lump, often no pain associated with early stages.

Front 159

Non cancerous breast lumps:

Back 159

- Cysts: squishy (can move and change in size during the menstrual cycle)
- Fibroadenomas: round with smooth surface (hard or soft)
- Pseudolumps: many causes, symptoms: get checked to be sure. (e.g., dead fat tissue or rib pushing on breast tissue).

Front 160

Can men get breast cancer?

Back 160

Yes, but 100 times less common in men

Front 161

Some factors that might increase the risk of Breast cancer:

Back 161

- Genetics (family history)
- Cigarette smoke (second hand too)
- Alcohol abuse
- Obesity
- Abnormal circadian rhythm

Front 162

Some factors that might reduce the risk of Breast cancer:

Back 162

- Lower age at first child birth (less than 24 years old)
- Having more children (7% lower risk per child)
- Breast feeding (4% lower risk per breastfeeding year)
- Mastectomy, Oophorectomy, or Hysterectomy:
a.) Mastectomy: removal of one or both breasts
b.) Oophorectomy: removal of ovaries
c.) Hysterectomy: removal of all or part of uterus

Front 163

Cancer treatments:

Back 163

- Immune system: macrophages and Natural killer cells can recognize cancer cells and destroy them.
a.) Vaccination: use antigens that are specific to the cancer cells
- Surgery: kills cancer cells, but kills healthy cells too. Ineffective if cancer has metastasized
- Radiation: stops mitosis so good against cancer cells, but damages other cells too. Ineffective if metastasis has occurred.
- Chemotherapy: relies on a wide range of drugs that find and destroy cancer cells or prevent the formation of supporting tissue (capillaries), which should help kill cancer cells.

Front 164

Asexual Reproduction

Back 164

Reproduction without sex, DNA comes from one individual

Front 165

Binary fission

Back 165

cell splits into two identical cells, Clones. Bacteria and some protists

Front 166

Budding

Back 166

genetically identical individual grow off other individuals

Front 167

Fragmentation

Back 167

pieces break off and grow into new individuals. Also called vegetative reproductive

Front 168

Parthenogenesis

Back 168

production of offspring from unfertilized eggs

Front 169

Advantages of Asexual reproduction

Back 169

don’t have to spend time looking for mates

Front 170

Disadvantages of asexual reproduction

Back 170

very little, if any, genetic variation among offspring

Front 171

Sexual Reproduction

Back 171

Meiosis and sex. DNA comes from two different individuals

Front 172

Disadvantages of sexual reproduction

Back 172

have to find and sometimes compete for mates

Front 173

Advantages of Sexual reproduction: combines

Back 173

independent assortment, segregation of alleles, recombination, and mutation, to create a lot of genetic variation

Front 174

Simultaneous Hermaphrodite

Back 174

has working male and female reproductive organs. Do not usually self-fertilize.

Front 175

Why not self-fertilize?

Back 175

Genetic variation

Front 176

Sequential Hermaphrodite

Back 176

individual born as one sex, but changes to the other

Front 177

Protandry

Back 177

born male, change to a female

Front 178

Protogyny

Back 178

born female, change to a male

Front 179

Genetic Gender Determination

Back 179

chromosomes determine gender of offspring

Front 180

Mosaic

Back 180

one egg, but a mitosis error early in development creates different populations of cells expressing different genotypes

Front 181

Bilateral Gynandromorph

Back 181

half the body is genetically male, half is genetically female

Front 182

Non-disjunction

Back 182

chromosomes do not segregate equally

Front 183

Chimera

Back 183

When different cells in the body have different genotypes. Cells derived from two different eggs that fuses

Front 184

SRY Gene

Back 184

negative regulatory protein. Y-linked gene that blocks gene expression on X chromosome.

Front 185

Androgen Insensitivity Syndrome

Back 185

mutation in Androgen receptor prevents receiving of male hormones. Genetic male (XY), phenotypic male.

Front 186

Environmental Gender Determination

Back 186

the environment determines the sex of offspring

Front 187

Temperature

Back 187

crocodiles, some turtles, some fish. Males and females develop at different nest temperatures (males 89.1 F and females 94.1 F)

Front 188

Environmental Toxins

Back 188

PCBs and other pesticides can ‘feminize’ male turtles and gulls

Front 189

Social Environment

Back 189

some fish and frogs can change sex if males or females are rare

Front 190

Fertilization

Back 190

Fusion of egg and sperm

Front 191

External fertilization

Back 191

occurs outside female’s body. Usually in wet environments

Front 192

Broadcast spawning

Back 192

release millions of gametes into the water and hope they find each other

Front 193

Internal fertilization

Back 193

occurs inside female’s body

Front 194

Internal Fertilization process:

Back 194

- Sperm penetrates egg coat
a.) Acrosome: sac of enzymes that allow the sperm to digest its way to the egg cell membrane
- Sperm and egg cell membranes fuse
- Fertilization membrane: membrane that prevents a second sperm from entering egg
- Sperm and egg nuclei fuse
- Egg implants into lining of uterus

Front 195

Fraternal Twins

Back 195

two or more different eggs are fertilized at the same time

Front 196

Identical Twins

Back 196

one fertilized egg splits into two genetically identical eggs

Front 197

Multiple births

Back 197

can be fraternal, individual, or a combination

Front 198

Humans typically have one baby at a time. Why do some animals have multiple offspring at a time?

Back 198

To ensure they produce enough offspring in a variable environment

Front 199

Three ways to handle a fertilized egg:

Back 199

1.) Ovipary: eggs lay outside the body
2.) Ovovivipary: eggs are kept inside body until hatching
3.) Vivipary: young develop inside female
a.) Placental mammal: developing embryo is connected to female’s body by a placenta and an umbilical cord
b.) Marsupial: young nourished outside female’s body inside a marsupium (pouch)