Biology 2023 with verified questions and answers

Mitochondrial DNA is _______, ________-stranded, with NO _______ nor _______ circular, double-stranded, NO telomeres or histone proteins Rough ER Smooth ER protein synthesis (ribosomes) lipid synthesis Golgi Apparatus where cellular modification occurs (in vesicles) Microtubules: 3 Types Cilia Flagella Centrioles Intermediate filaments function *Allow cell to withstand ________ forces cell-cell adhesion and cell integrity mechanical forces Endothelial cells line ______ veins, arteries, blood vessels Prokaryotic Ribosomes vs. Eurkaryotic Ribosomes 30S and 50S 40S and 60S Gram + Color: Gram - Color: peptidoglycan layer + lipoteichoic acid deep purple NO peptidoglycan layer + outer membrane pinkish-red Plasmids are: _______ are capable of integrating into the genome of bacterium small, circular, NON-CHROMOSOMAL DNA molecules (double-stranded) episomes Transformation extracellular DNA taken up by cell and incorporated into the genome Conjugation vs. Transduction transfer of DNA from one bacterium to another via a conjugation bridge (SEX PILI) vs. transfer of DNA from one bacterium to another via a BACTERIOPHAGE F Factors conjugation occurs from bacteria WITH F factor (Hfr) -- bacteria WITHOUT F factor (recipient) Transfection DNA (plasmids) are introduced into eukaryotic cells Positive-sense viruses vs. Negative-sense viruses genome can be directly translated by the ribosomes of the host cell vs. genome CANNOT be directly translated by the ribosomes of the host cell (complementary strand required by RNA replicase) Retroviruses are: single-stranded RNA viruses that are integrated into the host genome Use reverse transcriptase to convert RNA -- DNA Lytic Cycle vs. Lysogenic Cycle viral genome entry -- host genome degradation -- viral progeny replicates -- CELL LYSES viral genome entry -- viral genome integration into host genome -- cell division -- excision of viral genome -- cell DOES NOT lyse Prions infectious proteins that trigger misfolding of other proteins Viroids plant pathogens Interphase stages include G1, S, G2 (everything but mitosis) G0 stage: Occurs during _______ non-dividing, rest stage, performs everyday functions during G1 Phase G1 Stage organelle synthesis size increase S Stage DNA Replication G2 Stage protein synthesis continued cell growth 2 sheckpoints: G1 Checkpoint = cell decides it if should divide p53 in charge G2 Checkpoint = check cell size , organelles, & DNA replication for errors Positive Growth Signal vs. Negative Growth Signal CDK + Cyclin complex -- Rb phosphorylation -- cell division continues vs. CDK inhibitors block Rb phosphorylation -- cell cycle STOPS MITOSIS: Prophase Metaphase Anaphase Telophase Cytokinesis DNA condenses, centrioles move to opposite poles, microtubules form, nuclear envelope disappears chromosomes line up in the middle plate, spindle fibers attach chromatids are moved apart towards opposite poles chromosomes decondense, nuclear envelope reforms cellular division occurs MEIOSIS I: Prophase I Metaphase I Anaphase I Telophase I chromosomes condense, nuclear membrane dissolves, *CROSSING OVER can occur here chromosomes line up in the middle plate, spindle fibers attach separation of homologous chromosomes *DISJUNCTION occurs chromosomes decondense, cell divides into 2 HAPLOID daughter cells Crossing Over Occurs during which phase? occurs only between homologous chromosomes (NOT sister chromosomes) Prophase I Nondisjunction ONLY occurs during ________ (NOT _________) Can occurring during which phases? Failure of chromosomes to separate Meiosis, NOT Mitosis Anaphase I or Anaphase II Nondisjunction can result in: Polyploidy (monosomy/trisomy) Mendel's Law of Segregation the two copies of a gene segregate from each other during transmission from parent to offspring MEIOSIS II: Prophase II Metaphase II Anaphase II Telophase II chromosomes condense, nuclear membrane dissolves spindle fibers attach and align along equator sister chromatids are pulled apart to opposite poles chromosomes decondense, nuclear membrane reforms, cytokinesis to form 4 HAPLOID daughter cells For mitochondrial disorders, the ______ must be affected to be passed onto offspring mother, because ONLY maternal mitochondria are passed to offspring Leydig cells in the testes secrete _____ testosterone Sperm is produced (spermatogenesis) in the ______, nourished by ______ seminiferous tubules, Sertoli cells Pathway of Sperm *SEVE(N) UP Seminiferous tubules (testes) -- Epididymis -- Vas deferens -- Ejaculatory duct -- (Nothing) -- Urethra -- Penis Ova (eggs) are produced in the _______ follicles in the ovaries Ovaries produce estrogen and progesterone Estrogen is the response to ______ Progesterone is the response to _______ FSH LH *Estrogen Establishes, Progesterone Protects Zona pellucida Corona Radiata matrix that protects the oocyte layer of cells outside the zona pellucida that adhere to the oocyte Gonadotropin-releasing hormone (GnRH) Promotes secretion of FSH and LH In males: FSH stimulates _____ and triggers _______ LH triggers __________ Sertoli cells, spermatogenesis testosterone production In females: FSH stimulates _____ LH triggers _____ growth of ovarian follicles ovulation and estrogen production ... If there is no fertilization by sperm, E+P levels drop, menstruation occurs If there is fertilization by sperm, blastula produces human chorionic gonadotropin (hCG) Fertilization occurs in the ______ _______ reaction releases ______ ions, which ________ the membrane ampulla of the fallopian tube cortical, Ca2+, depolarize Cleavage (2 types) Indeterminate = results in cells that can still develop into complete organisms. vs. Determinate = results in cells that have determined fates and are committed to differentiation into another cell type. Blastulation embryo becomes a morula -- morula undergoes blastulation to form a blastula (hollow ball of cells) Morula solid ball of cells The blastula implants in the _________ endometrial lining Chorion develops into the _____ placenta Yolk Sac: Allantois: Amnion: supports/nourishes embryo fluid exchange thin, tough, fluid-filled membrane, shock absorber Blastula forms into the _______ gastrula Deuterostomes vs. Protostomes deuterostomes: anus developed first vs. protostomes: mouth developed first Ectoderm develops into _________ Cell types? - Develops into nervous system, hair, skin, nails - Gives rise to epidermis, neurons, melanocytes In Neurulation, Neural tube forms _____ Neural crest cells form ______ CNS PNS 3 Types of Stem Cells Totipotent = can be any type of cell. Give rise to BOTH placental and fetal cells Pluripotent = can be any cell in the 3 germ layers. Give rise ONLY to fetal cells Multipotent = is a specific subset of cell types. Fetal Hemoglobin (HbF) has a higher affinity for oxygen than adult hemoglobin Fetal Shunts (3 types): Foramen Ovale = Ductus Arteriosus = Ductus Venosus = Foramen Ovale = right atrium -- left atrium *Bypasses Lungs Ductus Arteriosus = pulmonary artery -- aorta *Bypasses Lungs Ductus Venosus = umbilical vein -- interior vena cava *Bypasses Liver Afferent Neuron Efferent Neuron Interneurons Afferent = from muscles/glands -- CNS SENSORY Efferent = from CNS -- muscles/glands MOTOR between other neurons Signal transmission occurs axon -- synapse -- dendrite of (next neuron) -- soma/cell body Tracts Carry only_____ type of information bundles of neurons in the CNS 1 type Nerves Carry ______ types of infomration bundles of neurons in the PNS multiple Oligodendrocytes ONLY located in the ______ produce myelin CNS Schwann cells ONLY located in the _______ produce myelin PNS Astrocytes Located in the _______ nourish neurons and form the blood-brain barrier CNS Ependymal Cells Located in the _______ Line the ventricles of the brain and produce cerebrospinal fluid CNS Microglia Located in the ________ immune/phagocytic cells, break down waste products CNS Nodes of Ranvier in myelinated neurons _________ increase the rate of neural signal transmission, however, voltage-gated ion channels are NOT evenly distributed along the axon Unmyelinated neurons lack ________ Nodes of Ranvier, therefore, voltage-gated ion channels are evenly distributed along the axon Steps of an Action Potential 1. Resting state - Channels are closed - Sodium/Potassium pump working (Na⁺ out +K⁺ in) * Resting potential is maintained 2. Depolarization - Na⁺ gates open, Na⁺ rushes into the cell - Membrane potential becomes POSITIVE 3. Repolarization - Na⁺ gates close, K⁺ gates open, K⁺ rushes out - Membrane potential becomes NEGATIVE 4. Hyperpolarization - Na⁺ gates still closed, K⁺ gates still open, K⁺ continues to leave - Membrane potential becomes NEGATIVE - Eventually, the K⁺ gates close - The membrane returns to resting state 5. Refractory period: time during which the cell membrane cannot form a new action potential A resting membrane potential is maintained by these 3 things ________ active transport passive transport membrane permeability Temporal summation: Spatial summation: same space, different time different space, same time White Matter vs. Gray Matter White = myelinated Gray = unmyelinated Brain has _______ matter inside, and _______ matter outside white inside, gray outer Spinal Cord has _______ matter inside, and _______ matter outside gray inside, white outer _________ synapses have a delay between the presynaptic and postsynaptic APs chemical synapses (neurotransmitters) Excitatory Response influx of + ions into the postsynaptic neuron -- DEPOLARIZATION -- AP fired Inhibitory Response efflux of + ions out of the postsynaptic neuron OR influx of - ions into the neuron -- HYPERPOLARIZATION -- AP NOT fired Excitatory neurotransmitter = Glutamate Inhibitory neurotransmitter = GABA Somatic PNS is Autonomic PNS is voluntary (skeletal muscles) involuntary (smooth muscles, glands) Autonomic PNS is divided into _______ and _______ __________ is responsible in the sympathetic __________ is responsible in the parasympathetic Sympathetic = fight or flight Parasympathetic = rest and digest Acetylcholine and Norepinephrine ONLY Acetylcholine Preganglionic neuron lies ________ the CNS Postganglionic neuron lies _______ the CNS within outside Peptide hormones are _______, ________ , and ________-soluble, Must bind to ________ receptors G-protein coupled receptors increase _______ levels Suffix is usually: Effects are usually ______, but _______ - ________ polar, charged, and water-soluble extracellular (GPCR receptors) cAMP -in or -ine rapid, short-lived Steroid hormones are _______, and ________. Derived from ________ and are ________-soluble Require a ________ to travel through the bloodstream, but can cross the _________ ________ Contain _______ receptors Effects are usually ______, but _______ - ________ Suffix is usually: nonpolar, small, cholesterol, lipid-soluble a carrier, cell membrane intracellular (nuclear receptors) slow, long-lived -one, -ol, -oid Epinephrine and norepinephrine behave as _________ hormones peptide Thyroxine and triiodothyronine behave as _________ hormones steroid Hypothalamus releases hormones into the ________ anterior pituitary Tropic hormones... vs. Direct hormones... hormones that stimulate other glands to release their hormones act directly on the target tissue (i.e. insulin) Hypothalamic Hormones -- Anterior Pituitary Horomones *FLAT PEG* GnRH -- FSH + LH GHRH -- GH TRH -- TSH CRH -- ACTH (cortisol) PIF/Dopamine -- No PIF = prolactin / PIF = NO prolactin Endorphins *FLAT = tropic hormones........PEG = direct hormones Posterior Pituitary Hormones (2) ONLY releases ______ hormones ADH/Vasopressin Oxytocin direct hormones Thyroid Hormones (2) T4 and T3 increase basal metabolic rate Calcitonin increases Ca2+ in bone and decreases Ca2+ in blood. Produced in the parafollicular (c-cells) Parathyroid Gland Hormone (1) Increases ________ in the blood Parathyroid hormone (PTH) Increases Ca2+ blood levels Adrenal Cortex Hormones Glucocorticoids: cortisol/cortisone Mineralocorticoids: aldosterone Androgens: testosterone + estrogen Aldosterone increases _______, which in turn increases _________ renal sodium reabsorption, blood pressure Adrenal Medulla Hormones (2) Both increase _______ and _______ catecholamines (epinephrine and norepinephrine) heart rate and blood pressure (sympathetic nervous system) Pancreatic Hormones (3) Insulin in beta cells Glucagon in alpha cells Somatostatin in delta cells -- decreases both insulin and glucagon levels. Released during HIGH glucose levels Pineal Gland Hormone (1) Melatonin Steps of Inhalation Diaphragm contracts -- thoracic cavity volume increases -- intrapleural space increases -- intrapleural pressure decreases -- rib cage elevates -- lungs expand and fill with air Due to negative pressure! Surfactant reduces _________ in the lungs surface tension The ________ in our brains controls breathing medulla oblongata Blood Buffer System Equation Path of blood flow through the heart Deoxygenated Blood: superior/inferior vena cava right atrium tricuspid valve right ventricle pulmonary valve -- pulmonary arteries lungs (receives oxygen) Oxygenated Blood: Pulmonary veins left atrium bicuspid/mitral valve left ventricle aortic valve aorta body Coagulation Prothrombin -- __________ Fibrinogen -- _________ Clots are broken down by _______ Thrombin (by thromblasatin) Fibrin (by thrombin) Plasmin Systole/Diastole means: ventricular contraction / ventricular relaxation *In ARTERIES, pressure in veins/capillaries DOES NOT CHANGE!!* Cardiac Output Equation CO = HR x SV (Cardiac output = Heart rate x stroke volume) Cardiac Electrical Conduction SA Node -- AV Node -- bundle of His -- Purkinje fibers Universal recipients are blood type ________ Universal donors are blood type ________ AB O MHC Class I is found in __________ ___________ pathway Displays to _______ cells all nucleated cells endogenous pathway/intracellular CD8+ T-cells (cytotoxic T-cells) MHC Class II is found in _________ _______ pathway Displays to _______ cells antigen-presenting cells exogenous pathway/extracellular CD4+ T-cells (helper T-cells) Professional antigen presenting cells include Macrophages B cells Dendritic cells Neutrophils Eosinophils Basophils activated by bacteria, conduct phagocytosis activated by parasites & allergens, release histamines activated by allergens, release some histamines Humoral Immunity involves _______ Cell-mediated immunity involve _______ B Cells T Cells B cells are produced in the _________, they mature in the ______, and are activated in the ______ T cells are produced in the _________, they mature in the ______ bone marrow, bone marrow, spleen/lymph nodes bone marrow, thymus Opsonization coats bacteria in a substance that makes them more appetizing to phagocytes to consume T-cell positive selection T cells that recognize MHC peptides are retained T-cell negative selection T cells that strongly bind to self-antigens are selected against and destroyed Active immunity can be a result of either _______ or ________ infection or vaccination Chief Cells secrete _______ in the _______. It's the inactive form of _______ pepsinogen, stomach, pepsin Parietal cells in the stomach secrete _______ and _________ HCl and intrinsic factor G-cells secrete _________ gastrin Bile is produced in the _______, stored in the ______, and released into the _________ liver, gallbladder, duodenum Pancreas contains _______ cells, which are _________ cells Pancreas exocrine function is ________ Pancreas endocrine function is ________ acinar, exocrine pancreatic enzymes released into the small intestine pancreatic hormones released into the bloodstream Liver produces ______ and ________ It synthesizes ________ which is a clotting factor When blood sugar is low, it produces _________ bile, bilirubin albumin glucose Fat-Soluble Vitamins are: ADEK (in that fat asss) Large intestine/colon parts cecum -- ascending colon, transverse colon, descending colon, sigmoid colon -- rectum Renal portal system capillary bed 1 is the _________ capillary bed 2 is the _______ glomerulus *Afferent arterioles move blood towards the glomerulus vasa recta *Efferent arterioles § move blood away from the glomerulus Nephron parts Proximal convoluted tubule -- Descending Loop of Henle -- Ascending Loop of Henle -- Distal convoluted tubule -- Collecting duct The _______ reflex is when the bladder is full and contracts the ______ muscles micturition reflex detrusor muscles Filtration is governed by _________ force and is a ________ process starling, passive Reabsorption Usually occurs with these molecules process whereby renal tubules return materials necessary to the body back into the bloodstream glucose, amino acids, and vitamins Acidosis vs. Alkalosis Acidosis = HCO3- reabsorbed, H+ secreted vs. Alkalosis = HCO3- secreted, H+ reabsorbed What occurs in the PCT? Glucose, water, vitamins, and salts are reabsorbed. Waste products secreted (H+ ions, K+ ions, ammonia, and urea) In the Loop of Henle: The descending limb is ___________ to water, while the ascending limb is __________ to water permeable, NOT permeable (only to salts) What acts on the DCT? Aldosterone, which promotes sodium reabsorption What acts on the collecting duct? Permeable during times of _________, while impermeable during times of ___________ Contains ________ ADH/Vasopressin Impermeable to water during times of hydration Permeable to water during times of dehydration/aldosterone present aquaporins Increase in pressure in the _________ and the __________ increase urine output Increase in pressure in the ___________ and the __________ decrease urine output renal artery and filtrate Bowman's capsule and peritubular capillaries Epidermis is derived from the _________ ectoderm Layers of the Epidermis stratum basale (melanocytes) stratum spinosum stratum granulosum stratum lucidum stratum corneum (water retention) The dermis is derived from the __________ Contains ___________ mesoderm sweat/oil glands, hair follicles, sensory receptors Desmosomes are anchoring junctions that anchor the cytoskeleton together Gap junctions: mediate cell-cell communications Tight junctions: prevent water and solutes from diffusing between cells Slow Twitch muscle fibers are _______ Fast Twitch muscle fibers are ________ red white Red fibers have ______ myoglobin, and many ________ high myoglobin, many mitochondria/capillaries White fibers have ______ myoglobin, and few ________ low myoglobin, few mitochondria/capillaries Skeletal Muscle Types Type I (red fibers) Type IIa Type IIx (white fibers) Slow, myoglboin/mitochondria rich, fatigue-resistant Fast, myoglobin intermediate, mitochondria rich, fatigue-resistant Fast, myoglobin/mitochondria poor, fatigues quickly Smooth Muscle exhibits ______ energy Connected by ________ junctions myogenic energy (can contract with nervous system signals, but does not require external signals to contract) gap junctions Cardiac muscle is connected by __________ discs and ________ junctions Exhibits __________ energy intercalated discs and gap junctions myogenic energy Dring sarcomere contraction, everything contracts EXCEPT the ______ A-Band