Exam 2 Review (Human Bio)

Compare and contrast DNA and RNA.

DNA:

• base - thymine

• sugar - deoxyribose

• strand # - 2

• ATGC

Similarities:

• contains genetic information

• made of nucleotides

RNA:

• base - uracil

• sugar - ribose

• strand # - 1

Identify the Central Dogma.

Which part is transcription?

Which part is translation?

Central Dogma: DNA → RNA → Protein

Which part is transcription? - DNA → RNA

Which part is translation? - RNA → Protein

Where does transcription occur?

Where does translation occur?

transcription - nucleus

translation - ribosome

Where are the 3 characteristics of codons?

1. Redundant

2. Triplets

3. Unambiguous

Identify which type of mutation has occurred in the following examples:

Original Sequence - UUA GGC AGC

1. UUA GGU AGC

2. UUA GUC AGC

3. UUA GGC AG

1. Substitution / Silent Mutation

2. Substitution / Missense Mutation

3. Frameshift Mutation

Know how to use this codon chart

Identify Mendel’s 4 concepts of inheritance

1. Genes have different versions called alleles.

2. Each organism inherits 2 alleles for each gene, 1 from each parent.

3. The dominant allele determines the organism’s appearance if the 2 alleles differ.

4. The Segregation of Law: Segregation of alleles occurs during gamete formation, so each gamete carries only 1 allele.

Color blindness is a sex-linked recessive trait. If a man is not color-blind and his wife is a carrier for color blindness, what is the likelihood that their son will have color blindness.

50% chance

Give 3 ways that the environment can affect phenotype.

1. Temperature can affect gender

2. Hormones can turn genes on/off

3. Drugs & chemicals can turn genes on/off

A female carrier for cystic fibrosis has children with a man that is also a carrier for cystic fibrosis. What is the likelihood that their children will have cystic fibrosis? Cystic fibrosis is recessive.

25% chance

A man with Huntington’s (a dominant disease) has children with a woman that does not have Huntington’s. What are the chances their children will have Huntington’s.

1) 100% chance

2) 50% chance

Rabbits will demonstrate incomplete dominance with fur color. When a homozygous black rabbit is crossed with a homozygous white rabbit, the resulting offspring will be:

Grey

What is codominance?

Both genes/alleles expressed (ex. spotted cow)

What is a test cross used to determine?

Whether an organism with a dominant phenotype has a homozygous dominant or heterozygous genotype.

(homozygous dominant or heterozygous determination)

A homozygous tall, heterozygous yellow pea plant is crossed with a heterozygous tall, green pea plant. What are the ratios of phenotypes for their offspring?

Tall, yellow = 8

Tall, green = 8

Short, yellow = 0

Short, green = 0

Identify 3 benefits of genetic testing

1. Early disease detection

2. Helps with informed medical decisions

3. Family planning

Which carcinogen causes the most cases & types of cancer?

Tobacco

Name 2 ethical concerns that should be considered with genetic testing

1. Privacy concerns (who owns your genetic code)

2. Emotional, social, & financial consequences

Which test analyzes fetal DNA using the mother’s blood?

Non-invasive prenatal

Which test obtains fetal cells from the amniotic fluid?

Amniocentesis

Which test is used for legal purposes to identify subjects?

Forensic

Which test detects genetic changes associated with a disease?

Predictive

Which test is used to rule out a specific genetic condition?

Diagnostic

What is the purpose of each of the following:

PCR =

Sanger Sequencing =

NGS =

PCR = make copies

Sanger Sequencing = sequence DNA

NGS = sequence thousands of genes at once

When surgery is used to remove a tumor, ____________ will also be removed. Afterward, it will be supplemented with ________ and ________.

When surgery is used to remove a tumor, normal tissue will also be removed. Afterward, it will be supplemented with chemotherapy and radiation.

Chemotherapy targets _______ cells, which means there can be side effects like _______ and ________.

Chemotherapy targets dividing cells, which means there can be side effects like hair loss and skin rash.

Define the following:

Hyperplasia -

Dysplasia -

Cancer in situ -

Invasive cancer -

Hyperplasia - non-cancerous growth from excessive cell division

Dysplasia - excessive cell division that’s somewhat abnormal cell proliferation (loss of tissue arrangement)

Cancer in situ - uncontrolled growth that remains in place

Invasive cancer - cancer that grows/spreads - invasive growth

Cancer is a ______ disease, caused by several _______ that accumulate throughout our lifetime.

Cancer is a genetic disease, caused by several mutations that accumulate throughout our lifetime.

What happens when p53 is mutated or absent?

Mitosis increases because of the normal tumor suppressors. (cell suicide won’t occur)

What are 3 things that can be done to help prevent cancer?

1. Avoid excessive sunlight

2. Avoid tobacco

3. Limit alcohol

Mutations in any of these 3 types of genes will most likely lead to cancer:

1. Proto-oncogenes

2. Tumor suppressor genes

3. DNA repair genes

What is reproductive cloning?

Technology used to create identical copy of entire multicellular organism. Results in birth of new living individual after implanting nucleus of somatic cell into a zygote.

The microenvironment in the specific location where stem cells interact with outside factors that regulate cell fate is know as a stem cell ______.

The microenvironment in the specific location where stem cells interact with outside factors that regulate cell fate is know as a stem cell niche.

When an adult cell is given reprogramming factors to become a pluripotent stem cell, it is known as an ______ pluripotent stem cell.

When an adult cell is given reprogramming factors to become a pluripotent stem cell, it is known as an induced pluripotent stem cell.

Are embryonic stem cells or adult stem cells typically used for therapies to treat diseases?

Embryonic

Define the stem cell types:

• Unipotent -

• Multipotent -

• Totipotent -

• Pluripotent -

• Unipotent - gives rise to only 1 cell type

• Multipotent - gives rise to some but not all cell types

• Totipotent - gives rise to any cell type in embryo and extra-embryonic cells

• Pluripotent - gives rise to all cell types of the body

Contrast GMOs and transgenic animals.

GMOs

• introduced artificially

• altered DNA segment

Transgenic animals

• gene from another species

• type of GMO

To make GMO plants, scientists use naturally occurring _________ based gene delivery systems.

To make GMO plants, scientists use naturally occurring Ti DNA based gene delivery systems.

Identify the 4 side effects of gene therapy

1. Targeting the wrong cells

2. Immune system reaction

3. Risk of cancer

4. Organ system failure

To edit the genome in a targeted way, scientists would use ________.

To edit the genome in a targeted way, scientists would use CRISPR / Cas9.

Understand the steps to create a transgenic animal.

1. Create a hybrid gene

2. Microinjection & embryo transfer

3. Transgenic animals is used for its purpose