BIO 1230 Learning Outcome Exam 2

Chromosome: DNA (which contains the genetic info of a cell) and specialized proteins, primarily histones.

Chromatin: DNA and associated proteins in a dispersed, rather than condensed, state.

Chromatid: One of the two identical replicates of a duplicated chromosome. The two chromatids that make up a chromosome are held together by a centromere and are referred to as sister chromatids. During cell division, the two strands separate and each becomes a chromosome in one of the two daughter cells.

Centromere: The region near the nucleus that contains centrioles. It forms the mitotic spindle during prophase.

Sister Chromatid: either of the 2 identical chromatids formed by replication of a chromosome during the S phase of the cell cycle. Joined through a centromere. Separated in mitosis during anaphase.

Condensed DNA: Cannot be replicated. Gene activity is shut down. Sister chromatids are easier to separate w/o breaking. 

Histones: proteins found in chromatin. One combined with DNA are for support and control of gene activity.

Somatic cells: all cells in your body except gametes.

Homologous pair: pair of each type of chromosome, one chromosome from mom and one chromosome from dad.

Interphase: Include G1, S, and G2. Makes up most of cell cycle.

G1 (Gap 1): primary growth phase

S (Synthesis): genome replicated (DNA replicated)

G2 (Gap 2): second growth phase

Mitosis: Genetically Identical Diploid(2n) Body Cells. 4 phases.

Prophase: Chromosomes condense.

Metaphase: Chromosomes (consisting of 2 chromatids) line up at equatorial plate (middle of cell).

Anaphase: The attachments between sister chromatids break

Telophase: Sister chromatids on opposite ends. New nuclei form, each with 2 complete sets of chromosomes

Cytokinesis: Divides cell into 2 daughter cells. Occurs near the end of mitosis. Splits cytoplasm.:

Meiosis: Genetically DIFFERENT(n) Haploid Gametes. A reduction division. 1 round of DNA replication and 2 rounds of cell division. 2n  → n

Meiosis in females: Occurs in ovary. Produces eggs

Meiosis in males: Occurs in testes. Produces sperm.

Meiosis 1: P1, M1, A1, T1, and cytokinesis.

Prophase 1: Crossing over occurs.

Metaphase 1: Chromosome line up at the middle in pairs

Anaphase 1: Spindle fibers attach to centromere and put away

Telophase 1: Two new nuclei are formed.

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Meiosis 2: = to Mitosis. 2n → 1n. Produces 4 daughter cells.

Prophase 2: Chromosomes condense.

Metaphase 2: Chromosomes (consisting of 2 chromatids) line up at equatorial plate (middle of cell).

Anaphase 2: The attachments between sister chromatids break

Telophase 2: Sister chromatids on opposite ends. New nuclei form, each with 2 complete sets of chromosomes

Cytokinesis: Divides cell into 2 daughter cells. Occurs near the end. Splits cytoplasm.:

Diploid cells: two sets of chromosomes. 2n

Haploid cells: one set of chromosomes. n

Gamete: sex cell

Somatic Cell: all other cells

Homologous Chromosome: 2 chromatids connected

Gene: located on chromosome

Locus: location of gene on DNA

Allele: alternative form of a trait

Stem cells: unspecialized cells. 

Totipotent: Can specialize to be any cell type.

Pluripotent: Can specialize to be nearly every type of cell

Multipotent: Can specialize to be many types of cells

Unipotent: Can specialize to be one type of cell.

Sources of stem cells: 1. native sources such as embryonic and umbilical stem cells. 2. Lab (creating embryonic stem cells from somatic cell nuclear transfer, cloning technology)

Uses of stem cells: Therapeutic Cloning and Reproductive Cloning.

Ovaries: Produces eggs. 

Oviducts: Tubes that conduct the egg toward the uterus.

Endometrium: lining of the uterus. Built up and lost each month as menstrual flow.

Uterus: House and nourishes the developing baby.

Cervix: opening of the uterus.

Vagina: muscular tube that receives the penis during sexual intercourse; the birth canal.

Testes: gonads in male. Outside the body.

Scrotum: loose sac containing the testes. Located outside of the body and functions to keep the testes cool.

Epididymis: attached to testis. Location of sperm storage and maturation.

Vas deferens: one of a pair of ducts that transport sperm from the epididymis to the urethra.

Prostate: Produces the fluid that nourishes and transports sperm.

Seminal vesicles: Provides fuel and energy. Alkaline.

Urethra: Tube through which sperm or urine leaves the body. In males, it is a shared structure (Reproduction system and Urine system).

Penis: The organ of sexual intercourse that delivers sperm to the female reproductive tract.

Foreskin: Protects the head of the penis

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Contraceptives that protect against STDs: Abstinence, Diaphragm and Cervical have some protection for women. Male and female condoms and spermicides.

Contraceptives that do not protect against STDs: Vasectomy, Tubal ligation, Oral (the pill), Injection, Vaginal ring, Skin patch, Minipill, Intrauterine, Fertility Awareness, Morning-after pill.

STDs that can be cured: Chlamydial infections, Gonorrhea, Syphilis, Trichomoniasis, Candidiasis. 

STDs that cannot be cured: Genital herpes, Genital warts, AIDS and HIV infections

Menstrual regulation: day 1 of the uterine cycle. Estrogen and progesterone are low. More FSH is produced causing a new egg follicle to develop and produce estrogen.

Spermatogenesis: Produces 4 different sperm.

Testosterone: Sperm production. 

GnRH: Stimulates anterior pituitary gland to release LH

LH in males: Stimulated production of testosterone.

FSH in males: Enhances sperm formation.

Inhibin: negative feedback. Inhibits FSH secretion. Decreases sperm and testosterone production.

Oogenesis (Egg production): Produces 1 functional egg and 3 polar bodies. Follicle surrounds the egg. Meiosis 2 never get completed unless fertilization occurs

Estrogen: Maturation of egg. Thickens endometrium of uterus to prepare for implantation of an embryo.

Progesterone: Prepares uterus for implantation of embryo. Maintains endometrium.

FSH in females: Stimulated development of a follicle in the ovary

LH in females: Triggers ovulation. Causes formation of corpus luteum.

Structure of DNA molecule: Double helix. Backbone made of deoxyribose sugar and a phosphate group. Contains 4 nitrogenous bases, A, T, C, G.

Complementary base pairing: A pairs with T, while C pairs with G. A and T paired with 2 hydrogen bonds. C and G paired with 3 hydrogen bonds

Replication of Genetic Code: Enzymes break hydrogen bonds of paired bases (Unzipping and unwinding strands). Free nucleotide bases attach to complementary bases on open DNA strands. DNA polymerases link sugars and phosphate of newly attached nucleotides to form a new strand. New DNA twists back into a double helix. Semi-conservative - One parent strand (the conserved strand) and one new strand.

DNA: Deoxyribonucleic acid, Sequence of nucleotides carries instructions for making proteins. Contains genetic code. 

RNA: Ribonucleic acid. Single stranded. Contains ribose (sugar), phosphate, and Base pairs of A, U, C, and G. A pairs with U. C pairs with G. Important in protein synthesis.

Protein Synthesis: Carried out by RNA. includes transcription and translation. 

Transcription: DNA → RNA. Occurs in the nucleus. DNA unwinds. RNA nucleotides pair with DNA bases and linked together to form RNA. 

The genetic code: language of genes.

Codons: sequence of three bases on mRNA that specify 1 amino acid, the beginning or end of the protein chain.

Anticodon: three base sequence on tRNA. binds to codon on mRNA.

Messenger RNA (mRNA): Coded instructions for protein synthesis (codons). Carries DNA’s instructions from nucleus to cytoplasm. 

Ribosomal RNA (rRNA): Part of the ribosome. Combines with proteins to form ribosomes. 

Transfer RNA (tRNA): Carry specific amino acids to ribosomes to be added to polypeptide chain (anticodon). 

Introns: unexpressed regions of DNA

Exons: expressed regions of DNA

Translation: RNA → Protein. 3 parts: Initiation, elongation, and termination.

Initiation: mRNA, tRNA, and ribosomes come together.

Elongation: additional amino acids are added to chain.

Termination: Occurs when stop codon moves into ribosome.

Epigenetics: Regulating gene activity. Study of what turns genes on and off. Affected by coiling and uncoiling of DNA. 

Recombinant DNA: Novel genetic make up using two sources of DNA. Using recombinant DNA to fundamentally change an organism. Gene of interest sliced out of original organism and spliced into vector DNA. Vector used to transfer the gene to a new host cell. The recombinant organism containing the gene is identified and isolated from the mixture of recombinants. The gene is amplified through bacterial cloning or by use of a polymerase chain reaction. 

Genetic engineering: manipulation of genetic material for human practical purposes. 

Value of genetic engineering: Used to produce pharmaceuticals and hormones, improve diagnosis and treatment of human diseases, increase food production from plants and animals, and gain insight into the growth processes of cells.

Application of genetic engineering to plant, animal, environmental science: Plant - Used in making crops resistant to pests and herbicides. Make food more nutritious. Animal - Used on livestock. Vaccines. Enhance milk production. Environmental science - sewage treatment plants, genetically engineered microbes lessen the amount of phosphate and nitrate discharged into waterways

Biotechnology: Applied biology

Aspects of biotech: Genetic Engineering/Bioengineering. Cloning. Stem Cells. Cell and Tissue Culture. Applications - Medicine. Agriculture. Industry. Forensics and Identity Science. GMOs - Genetically Modified Organisms

Controversies of biotech: Safety. Ethical controversy. Not enough long term effect known. Potentially harm that could occur. 

Gene sequencing: Determine entire genetic makeup of an organism or cell type. \n Use of gene sequencing: Give scientists a greater ability to diagnose, analyze, and treat many diseases with genetic bases. Help discover diseases early on.

Limits of gene sequencing: Accuracy. Time consuming.

Polymerase Chain Reaction: A way of making multiple copies of DNA. 

Gel electrophoresis: A way of using small differences in individual’s DNA (STR).Separates DNA fragments based on size. DNA is cut with Restriction Endonucleases. Larger fragments move slower and smaller fragments move faster.

Uses of gel electrophoresis: Used to identify individuals, trace relatedness, solve crimes

Purpose and value of Human Genome Project: finding out what all genes code for. Help identify genes involved with diseases. 

Purpose and value of Gene therapy: Put functional genes into body cells affected by defective (mutant) gene. Potential to cure inherited diseases.

Purpose and value of CRISPr: editing genes. Could cure some genetic diseases and other similar things.