Genetics and Biology Reviewer PDF

GENBIO: GENETICS: Gregor Johann Mendel: -​ Born in 1822, Austrian Empire (Town now in Czech Republic), had a poor farming family -​ Father of Modern Genetics -​ Went to University of Vienna for his teaching diploma -​ Monk, Botanist, Teacher -​ Had a father who bred fruit trees,...

GENBIO: GENETICS: Gregor Johann Mendel: -​ Born in 1822, Austrian Empire (Town now in Czech Republic), had a poor farming family -​ Father of Modern Genetics -​ Went to University of Vienna for his teaching diploma -​ Monk, Botanist, Teacher -​ Had a father who bred fruit trees, he gained interest in it and studied other plants which lead him to studying Garden Peas Mendel lived at the monastery, became a priest when he was 25 years old. Studied many sciences, taught Latin, Greek and math to other students. Characteristics of Living Things: Species Characteristics- all members of a species are alike Individual characteristics- characteristics that make a member of species different from another Factors that Influence Individuality: Heredity- process of transmitting biological traits from parent to offspring (thru genes) Environment- may affect an individual’s growth Gregor Johann Mendel: -​ Born in 1822, Austrian Empire (Town now in Czech Republic), had a poor farming family -​ Father of Modern Genetics -​ Went to University of Vienna for his teaching diploma -​ Monk, Botanist, Teacher -​ Had a father who bred fruit trees, he gained interest in it and studied other plants which lead him to studying Garden Peas Mendel’s study of Green Peas: Peas had a short breeding time. Could be Cross-Pollinated, Mendel is said to have 34 different varieties of Pea plants. Overtime he grew and tested at least 28 000 Pea plants in his garden. Heredity - an organism’s set of characteristics it receives from its parents Genetics- Study of Heredity Mendelian Genetics- Early Experiments: Used the pea plant because: -​ They grow quickly -​ They reproduce by self- pollination -​ Possess characteristics that can be easily recognized  -​ Pollination can be controlled in this group of plants with min work -​ Garden peas produce enough offspring to conduct a study The original cross: Mendel crossed pea plants (1 tall and 1 short) -​ P(parentis) stands for the parent -​ Offsprings of the crossed are called hybrids -​ He called the hybrids F1 generation. F means fillius meaning son Result: traits didn’t blend, one showed up and one vanished -​ Mendel crossed the results of F1 generation and called the next generation F2 Result: some traits that had vanished reappeared in F2, in approximately ¼ of the plants 3 important conclusions from these experimental results: 1.​ Inheritance of each trait is determined by units or factors that are passed on to descendants unchanged 2.​ A trait may not show up in an individual but can still be passed on to the next generation 3.​ Individual inherits one such unit from each parent for each trait Dominant vs. Recessive Alleles: Dominant(Aa)- expresses its trait with just one copy Recessive(Aa) - requires 2 copies to show its trait Allele- variant of a gene found at a specific location on a chromosome Influences traits like eye color, hair color, blood type etc. Trait- characteristics that differentiates one from others Principles of Mendelian Genetics: Principle of Dominance and Recessiveness- If an organism inherits different alleles for the same trait one allele may be dominant over the other Principle of Segregation- each gene, an organism receives 1 allele from each parent. Alleles separate from each other when reproductive cells are formed Principle of Independent Assortment- Some genes segregate independently, this law describes how different pairs of alleles for different traits assort independently of one another during formation of gametes. Phenotype: Form of trait it displays, appearance Genotype: genetic makeup of a single/group of organisms regarding a single or set of traits. Homozygous: If both recessive and both dominant alleles ex: AA, aa Heterozygous: if it has mixed pair of alleles ex: Aa Monohybrid cross: A cross between individuals that involves 1 pair of contrasting traits Dihybrid cross: A cross between individuals that involves 2 pairs of contrasting traits Punnett Square: Used by biologists in predicting probabilities of the outcomes of genetic crosses. Probability: a possible future event might occur in any given instance of the event -​ Homo/Homo-mono: all the same -​ Homo/Hetero-mono: ½ homo, ½ hetero -​ Hetero/Hetero: 1homo dominant, 2 hetero, 1homo recessive -​ General Dihybrid Crosses: 9:3:3:1 Color Blindness- Genetic Condition, no cure for it. Red/Green Color Blindness is the most common type of this condition. INTEGUMENTARY SYSTEM: Body’s outer layer, made up of skin, nails, hair, glands and nerves on the skin. It acts as a physical barrier protecting you from bacteria, infection, injury and sunlight. Helps regulate body temperature and allows you to feel skin sensations. PARTS: Skin- Largest and heaviest organ of the body Layers of the Skin: ​ Epidermis- Top layer, made up of 3 types of cells (melanocytes, keratinocytes, langerhans), gives the skin its color and provides a waterproof barrier Layers of Epidermis: 1.​ Stratum Basale: -​ deepest layer, new skin cells develop here -​ contains keratinocyte stem cells that produces keratin  -​ Contains melanocytes which produces melanin that is responsible for the pigment of the epidermis 2.​ Stratum Spinosum: -​ Consists of keratinocytes held together by sticky proteins desmosomes -​ Helps skin to be flexible and strong 3.​ Stratum Granulosum: -​ Keratinocytes have granules within them, these are visible under a microscope -​ Keratohyalin granules help bind keratin filaments together. This creates a barrier that prevents water and other substances from passing through the epidermis 4.​ Stratum Lucidum: -​ Between stratum granulosum and stratum corneum -​ Thin transparent layer of keratinocytes that are becoming less round and has a flatter shape -​ Reduces friction between the 2 layers 5.​ Stratum Corneum: -​ Outermost layer -​ In this layer, keratinocytes becomes corneocytes -​ Corneocytes are strong, dead keratinocytes, protects you from harm, abrasions, light, heat and pathogens -​ Consists of fats that keep water from easily entering/leaving the body ​ Dermis: -​ Middle and thickest layer of the skin -​ Contains sweat, oil glands and hair follicles Layers of the Dermis: 1.​ Reticular Dermis: -​ Bottom layer -​ Net-like structure of elastin and collagen fibers that surrounds reticular dermis -​ The fibers support skin’s overall structure, allows it to move and stretch 2.​ Papillary Dermis -​ Much thinner than reticular dermis -​ Extends to the basement layer of the epidermis -​ Forms a strong bond that connects like interlocking fingers 3.​ Hypodermis ​ Hypodermis: -​ Bottom and fatty layer of the skin -​ Helps insulate the body, this layer is aka subcutaneous layer/ superficial fascia ​ Hair:  -​ Keeps heat in our body, made out of protein called keratin -​ Eyelashes and eyebrows protect eyes from dirt and water 1.​ Hair shaft: -​ Part of hair that you can see, touch and style 2.​ Hair Follicle: -​ Tube-like structure, keeps your hair in your skin 3.​ Hair bulb: -​ Located under the skin and is responsible for hair growth Dandruff: causes white/yellow flakes in the scalp and hair shaft. AKA seborrheic dermatitis Head lice: tiny, crawling insects that lives in a person’s head hair Hirsutism: Excessive hair growth in people assigned female at birth Hair loss: most common condition that affects the hair, some are temporary, some are permanent. Most common types: Alopecia Areata- packets of hair loss caused by an autoimmune disease Anagen Effluvium- loss of hair during growth phase, often occurs during medical treatments like chemotherapy Androgenic Alopecia- baldness in both genders, based on genetics Telogen effluvium- loss of hair during its rest phase. shows up months after body goes through something stressful or hormonal changes Traumatic Alopecia- Hair loss due to damage to scalp from hair styling DIGESTIVE SYSTEM: Group of organs that break down food to absorb nutrients used for energy, cell repair and growth. Process: 1.​ Ingestion: involves mastication/chewing. Salivary glands along the tongue help moisten and lubricate food before being pushed down into the food pipe 2.​ Mixing and Movement: Process of lubricating and manipulating food and pushing it down through the food pipe and into the stomach 3.​ Secretion: Stomach, small intestine, liver, and pancreas secrete enzymes and acids to aid the process of digestion. Breaking down food particles into simple components and easily absorbable components 4.​ Digestion: process of converting complex food particles into simpler substances in the presence of enzymes and acids secreted by different digestive organs 5.​ Starts in the small intestine where most nutrients and minerals are absorbed, excess water in the indigestible matter is absorbed by large intestine 6.​ Excretion: removing indigestible substances and waste-by-products from the body through defecation Parts: Mouth: Digestive process starts in the mouth through chewing. Saliva has an enzyme that begins to break down starches in our food Esophagus: Transport food entering the mouth through the through and to the stomach Stomach: holds the food and mixes with acid and enzymes to break down food into a liquid or paste Small intestine: absorbs nutrients and water by breaking down the food and fluids consumed Large intestine: absorbs water and salts from indigestible substances and get rid of any waste products leftover Rectum: holding area for stool, when full, it pushes stool out of the body through anus How to keep DIGESTIVE SYSTEM Healthy? 1.​ Drink enough water- helps food flow more easily 2.​ Get your fill of fiber- enough fibers, keep your digestive system working as it should 3.​ Add probiotics- good bacteria that fight bad bacteria in the system 4.​ Eat mindfully- slow down and chew food thoroughly 5.​ Avoid alcohol and smoking- can increase amount of acid in stomach and cause heartburn Respiratory System: Set of organs and structures in the body that allows you to breathe. Includes lungs, mouth, nose and tube-like structures that connect them. Breathing- process of moving air into and out of the lungs Inspiration: Inhaling, primary purpose is to bring oxygen into the lungs Expiration: exhaling, primary purpose is to release carbon dioxide from the body Oxygen Travel: -​ Air enters nose/mouth cavity, passes through pharynx and larynx, trachea carries air down into bronchi -​ Bronchi divides into smaller bronchioles, leads to clusters of alveoli in the lungs -​ Oxygen diffuses into bloodstream, CO^2 diffuses out of the bloodstream into the alveoli -​ Diaphragm relaxes, pushing air out of the lungs, air exits trachea, larynx and nose/mouth Parts: ​ Lungs: Main organ of this system, 2 lungs are responsible for making oxygen available to the body and remove gasses like CO2  ​ Nose and Nasal Cavity: Primary entry point for air, nasal cavity filters incoming air removing dust and particles before it reaches the lungs ​ Mouth and Oral Cavity: Alternate entry point for air, oral cavity plays a minor role in respiration but essential for speech and swallowing ​ Sinuses: air-filled spaces in the skull, produces thin mucus to trap small elements and pollutants, humidifying air before it reaches the lungs. ​ Pharynx/Throat: muscular tuber in the middle of the neck, connects nasal cavity, mouth to trachea. Pathway for air and food. -​ Epiglottis: flap-like structure, prevents food from entering trachea during swallowing ​ Larynx(Voicebox): Tough, flexible part of the respiratory tract, connects pharynx to the trachea(windpipe), allow air to pass while preventing food and drink from blocking airways ​ Trachea/Windpipe: Long, U-shaped hollow tube that connects larynx to bronchi. Enable airflow to and from the lungs ​ Bronchi: main airways of the lungs, has tiny hair-like structures(cilia), help move out mucus out of lungs, keeping bronchi clean and healthy ​ Bronchioles: small, branching air passages inside lungs. Serve as conduits for air, connecting larger bronchi to alveoli ​ Alveoli: there are 300 million alveoli, tiny air sacs located at the end of bronchioles. Play crucial roles in gas exchange during breathing Respiratory Diseases: Asthma, Tuberculosis, Pneumonia, Lung Cancer Ways to take care respiratory system: EXCRETORY SYSTEM -​ Biological system that secretes unnecessary waste from the body fluids of an organism Focuses on addressing 2 major issues: 1.​ Maintaining Osmotic Balance 2.​ Removing Metabolic Waste ​ Skin - excrete water & other substances ​ Liver - detoxification and produces urea ​ Lungs - excretes co2 ❖​Nephron -​ Functional unit of the kidney -​ Process waste products from the urine -​ Millions are present inside the kidneys ❖​Glomerulus -​ Cluster of capillaries -​ Main filtering unit of the kidney ❖​Filtrate -​ The fluid that is the product of filtration Parts Responsible for Creating Urine Bowman’s Capsule -​ Part of nephron that forms a cup-like sack surrounding the glomerulus -​ Helps glomerulus filter blood Proximal Tubule -​ Segment of nephron in kidneys -​ Reabsorption of filtrate (glucose, amino acids, phosphate, citrate) Loop of Henle -​ Long U-shaped portion of the tubule -​ Conducts Urine within each nephron -​ Reabsorb salt and water Distal Convoluted Tubule (DCT) -​ Nephron segment -​ Between the loop of henle and collecting tubule  -​ Regulating extracellular fluid volume and homeostasis Collecting Duct -​ Receives and concentrates urine from DCT Bowman’s Capsule -> Proximal Tubule -> Loop of Henle -> DCT -> Collecting Duct -> Ureter -> Bladder -> Urethra Main Organs of The Excretory System Kidney -​ Cleans toxins and waste out of your blood -​ Bean shaped-structure Ureter -​ Pair of thin muscular tubes -​ Extends from the renal pelvis -​ Tube that carries urine from the kidney to the bladder Bladder -​ Hollow, spherical organ -​ Stores urine Urethra -​ Tube that lets urine leave your bladder -​ Located in your body’s pelvic region CIRCULATORY SYSTEM -​ Made up of blood vessels that carry blood away from and towards the heart -​ Delivers oxygen and nutrients to cells ❖​Heart -​ Pumps blood around the body -​ Right (Deoxygenated) Left (Oxygenated) -​ Contains valves to prevent backflow of blood Parts of The Heart Vena Cava -​ Large vein -​ Bring DeOx blood from the other areas -> heart -​ Superior & Inferior Right Atrium -​ Receives DeOx blood from body -​ Pumps it to the right ventricle Right Ventricle -​ Pumps DeOx blood to the lungs Pulmonary Artery -​ Transport DeOx blood from right side of the heart to lungs for oxygenation Pulmonary Vein -​ Carry oxygenated blood from lungs to heart Left Atrium -​ Receives oxygenated blood from lungs -​ Pumps it to left ventricle Left Ventricle -​ Receives oxygenated blood from Left Atrium -​ Forces oxygenated blood through aortic valve Aorta -​ Delivers oxygenated blood to your body Valves In The Heart Pulmonary Valve -​ Helps manage blood flow -​ Controls the flow of DeOx blood from heart to lungs Tricuspid Valve - ​ Opens and ensures that blood flows in the correct direction - ​ Located between R.V and R.A Mitral Valve - ​ “Bicuspid valve” - ​ Regulates blood flow from L.A into L.V Aortic Valve - ​ Between L.V and Aorta - ​ Ensures that oxygenated blood does not flow back into L.V