Science Reviewer 3rd Quarter PDF

SCIENCE QE REVIEWER BY: 10-AOM (ASHLEY SANTOS, FEMMELA CHAN, DANIELLA FERNANDEZ) 3 MUSKETEERS POINTERS: 1.​ Menstrual Cycle 2.​ DNA vs. RNA a.​ Complementary Base Pairings in DNA and RNA 3.​ Central Dogma of Molecular Genetics a.​...

SCIENCE QE REVIEWER BY: 10-AOM (ASHLEY SANTOS, FEMMELA CHAN, DANIELLA FERNANDEZ) 3 MUSKETEERS POINTERS: 1.​ Menstrual Cycle 2.​ DNA vs. RNA a.​ Complementary Base Pairings in DNA and RNA 3.​ Central Dogma of Molecular Genetics a.​ Protein Synthesis through: -​ Replication -​ Transcription -​ Translation 4.​ DNA Mutation a.​ Gene Mutation and Chromosomal Mutation b.​ Genetic Disorder MENSTRUAL CYCLE is the cycle of physiological changes from the beginning of one menstrual period. ​ MENSTRUATION -​ The regular discharge of blood, uterine tissues, and unfertilized egg cells. a.​ MENARCHE -​ The first on-set of menstruation. ​ DYSMENORRHEA -​ is also called Menstrual Cramps. -​ characterized by throbbing or cramping pains in the lower abdomen. -​ may occur before and during their menstrual periods. PHASES OF THE MENSTRUAL CYCLE ​ LUTEINIZING HORMONE (LH) ​ CORPUS LUTEUM -​ Responsible for releasing the -​ is made from a follicle that houses a matured egg cell in the ovary. maturing egg. -​ Aids in egg maturation. -​ A corpus luteum is a mass of cells -​ Provides the hormonal trigger to that forms in an ovary. It is a cause ovulation (release of eggs temporary organ that appears every from the ovary). menstrual cycle and disappears if fertilization does not occur. ​ WHY IS THE MENSTRUAL CYCLE SIGNIFICANT AMONG FEMALES? 1.​ REPRODUCTION -​ The cycle prepares the body for potential pregnancy by regulating ovulation, the release of an egg from the ovary. 2.​ HORMONAL REGULATION -​ It helps maintain a balance of hormones such as estrogen and progesterone, essential for various bodily functions. 3.​ HEALTH INDICATOR -​ A regular menstrual cycle is often a sign of good health, while irregularities can signal underlying medical conditions like hormonal imbalances or stress. 4.​ ENDOMETRIAL RENEWAL -​ The shedding of the uterine lining during menstruation ensures a healthy environment for embryo implantation in future cycles  ​ NOTES 1.​ How many days is the regular menstrual cycle? -​ 28 days – regular menstrual cycle. 2.​ How many days is the flow of menses? -​ 3 to 7 days – the flow of menses. 3.​ On what day has the egg been released or ovulated? -​ 14th day of 28 days REGULAR cycle – ovulation or release of egg cells. 4.​ Describe the uterine wall – endometrium on days 21-28. -​ The endometrium thickens on days 21-28. 5.​ human chorionic gonadotropin (hCG) is the hormone pregnancy tests detect DNA VS RNA ​ CHROMOSOME -​ A chromosome is a packaged and organized chromatin, a complex of macromolecules found in cells, consisting of DNA and protein. > DNA - Deoxyribonucleic acid > RNA - Ribonucleic acid ​ FUNCTIONS OF A CHROMOSOME https://www.youtube.com/watch?v=d_-XWjlhLyk https://www.youtube.com/watch?v=-hryHoTIHak 1.​ It stores and transmits HEREDITARY information in the form of GENES. 2.​ Ensure accurate replication and distribution of DNA during cell division (mitosis & meiosis). ​ GENES -​ Are segments of the DNA. -​ They carry the genetic information of an organism.  ​ HUMAN CHROMOSOMES -​ 23 pairs or 46 chromosomes -​ 22 pairs or 44 body chromosomes/ autosomes -​ 1 pair or 2 sex chromosomes ​ HAPLOID CHROMOSOME ​ DIPLOID CHROMOSOME -​ Unduplicated. -​ Duplicated. -​ With half the number of -​ With a complete number of chromosomes. chromosomes. -​ Contains 23 chromosomes. -​ Contains 46 chromosomes. EXAMPLE: EXAMPLE: -​ Gametes or sex cells (sperm and -​ Somatic cells or body cells (skin, RBC, egg cells). hair, bone, etc.) STRUCTURES OF THE DNA ​ PIONEERS OF THE DNA MODEL (1953) 1.​ James Watson 2.​ Francis Crick ​ NITROGEN BASES OF DNA 1.​ Adenine (A) 2.​ Cytosine (C) 3.​ Guanine (G) 4.​ Thymine (T) ​ CHARGAFF’S RULE OF DNA -​ The amount of Adenine (A) = The amount of Thymine (T) -​ The amount of Guanine (G) = The amount of Cystosine (C)  ​ NITROGEN BASES OF RNA 1.​ Adenine (A) 2.​ Cytosine (C) 3.​ Uracil (U) 4.​ Guanine (G) THE CENTRAL DOGMA OF MOLECULAR GENETICS ​ DOGMA -​ A principle or set of principles. ​ REPLICATION -​ Copying or duplication of DNA before cell division. ​ TRANSCRIPTION -​ DNA is copied into messenger RNA (mRNA) in the nucleus. ​ TRANSLATION -​ mRNA is decoded by ribosomes in the cytoplasm to assemble a specific protein. ​ CODON -​ A sequence of three nucleotides in mRNA that codes for a specific amino acid. ​ NUCLEOTIDE -​ The basic unit of DNA and RNA, consists of a sugar (deoxyribose or ribose), a phosphate group, and a nitrogenous base (A, T, C, G in DNA; A, U, C, G in RNA). ​ AMINO ACID -​ building blocks of proteins. ​ PROTEIN -​ A complex molecule made of amino acids that performs various functions in the body, such as enzymes, hormones, and structural components.  ​ THE CENTRAL DOGMA OF MOLECULAR GENETICS -​ Explains the flow of genetic information, from DNA to mRNA (TRANSCRIPTION), to make a functional product, a protein (TRANSLATION). -​ states that the pattern of information that occurs in our cells are: 1.​ From existing DNA to make new DNA (replication) 2.​ From DNA to make new mRNA (transcription) 3.​ From mRNA to make new proteins (translation) EXAMPLE: https://www.youtube.com/watch?v=gG7uCskUOrA DNA MUTATION -​ Di pa po nalelesson : ( -​ Thanks imacu 😀 ​ MUTATIONS -​ are changes made to an organism’s genetic material. -​ changes may be due to errors in replication, errors during transcription, radiation (exposure to mutagens), and viruses (viral infection). ​ FACTORS THAT CAUSE DNA MUTATION 1.​ RADIATION -​ UV Radiation: Both natural sunlight and tanning beds. -​ X-ray: Medical, dental, Airport security screening.  2.​ CHEMICALS -​ Cigarette Smoke: Contain dozens of mutagenic chemicals. -​ Nitrate & Nitrite Preservatives: Found in processed meats. -​ Barbecuing: Creates mutagenic chemicals in foods -​ Benzoyl Peroxide: Common ingredient in acne products. 3.​ INFECTIOUS AGENTS -​ Human Papillomavirus (HPV): Sexually transmitted virus. -​ Helicobacter pylori: Bacteria spread through contaminated food. ​ TYPES OF MUTATIONS 1.​ GENE MUTATION - GENE ALTERATION -​ A change in one or more genes can lead to genetic disorders or illness. 2.​ CHROMOSOMAL MUTATION - CHROMOSOMAL ABNORMALITY -​ Changes to the structure or number of chromosomes. ​ FIVE TYPES OF CHROMOSOMAL MUTATIONS ​ POINT MUTATIONS -​ Large category of mutations that describe a change in a single nucleotide of DNA, that causes that DNA to be different from the normal type of gene sequence. 1.​ INSERTION -​ Extra base pair is added to a sequence of bases. a.​ BETA-THALASSEMIA -​ Blood disorder that reduces the production of hemoglobin. 2.​ DELETION -​ Extra base pair is deleted from a sequence. -​ Loss of a part. -​ Loss of large regions of a chromosome. a.​ CYSTIC FIBROSIS  -​ Hereditary disease that affects the lungs and digestive system. -​ The body produces a thick and sticky mucus that can clog the lungs and obstruct the pancreas. 3.​ DUPLICATION -​ Extra copies of a sequence. -​ Duplication of a few bases. 4.​ INVERSION -​ The order of genes in the chromosomes is inverted 5.​ TRANSLOCATION -​ Part of one chromosome is transferred to another chromosome.\ ​ GENETIC DISORDER -​ Caused by DNA mutations. -​ Heritable or inheritable. ​ EXAMPLES OF GENETIC DISORDER 1.​ TAY-SACHS DISEASE -​ Recessive gender disorder. -​ Abnormal accumulation of GM2 (fatty substance) -​ Defect in HEXA gene (hexosaminidase)? -​ Muscle weakness. -​ Speech problems. -​ Impaired cognitive and motor functions. a.​ HEXASAMINIDASE-A -​ Brain and spinal cord. -​ Enzymes found at lysosomes. -​ Break down toxic substances and act as recycling centers. 2.​ SICKLE CELL ANEMIA (SCA) -​ Single gene disorder -​ Hemoglobin gene  -​ Chromosome 11 -​ Hydrophobic amino acid (valine) replaces hydrophilic acid -​ Red blood cells become sickle -​ Pain in arms, legs, chest and abdomen -​ Recurrent infections 3.​ PHENYLKETONURIA (PKU) -​ Protein phenylalanine hydroxylase (PAH) -​ Phenylalanine to tyrosine -​ Normal at birth -​ Stunted growth -​ Epilepsy -​ Behavioral problems -​ Skin rash -​ Mouse-like body odor 4.​ HEMOPHILIA -​ Impaired blood-clotting ability -​ Bleed longer -​ Bleed internally 5.​ CRI-DU-CHAT SYNDROME -​ Cat’s cry syndrome -​ Chromosome 5 is missing -​ Low birth and poor growth -​ Severe cognitive, speech, and motor delays -​ Behavioral problems (tantrums, hyperacidity, motor delays) 6.​ DOWN SYNDROME -​ Trisomy 21 -​ Mild to serious physical and developmental problems -​ Congenital cardiac -​ Gastrointestinal anomalies -​ Autoimmune conditions -​ Respiratory infections -​ Sleep disorders  -​ Hearing and vision loss 7.​ EDWARD’S SYNDROME -​ Trisomy 18 -​ Babies born with the condition usually do not survive for much longer than a week