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BIOLOGY

Compiled and made by: Redeem

ANATOMY

Pulmonary Circulation

Thermoregulation - homeostasis; Maintenance of stable body temperature regardless of external conditions. Endotherms - warm-blooded animals; Regulates internal temperature; Conserves heat countercurrent exchange Ectotherms - cold-blooded animals; Gain and lose heat by the way of the environment Heart Cycle - contraction of the heart Systole - contraction occurs Diastole - relaxation occurs

• Beat begins in tissue in the R. Atrium called Sinoatrial (SA) node. Impulse spread both atria and conducts directly to atrioventricular (AV) mode. Action potential from AV node to the bundle of His and then to the Purkinje fibers in the walls of both ventricles. BLOOD All blood cells are made in the Bone Marrow

1. Plasma
2. Cells and cell fragments suspended in the fluid a. Red blood cells (Erythrocytes) - contains hemoglobin (specific protein that actually carries oxygen and carbon dioxide); Mature RBC lacks nucleus. b. White blood cells (Leukocytes) - fight infections and protect body against foreign organisms. c. Platelets - responsible for blood clotting Blood types - specific blood type contains specific antibodies that will destroy blood of different blood type from transfusion. Type O - Universal donor Type AB - Universal recipient Homostasis - sequence of responses that stops bleeding. 3 Mechanisms reduce blood loss:

1. Vascular spasm 2) Platelet plug formation 3) Blood clotting Blood clotting stage sequence: Platelets rupture -> Prothrombin (thromboplastin) -> Thrombin -> Fibrinogen (thrombin) -> Fibrin + erythrocytes form a hardened clot Red Blood Cells - contain the oxygen-carrying protein Hemoglobin. Hemoglobin is pigment that gives whole blood its red color. Male: 5.4m RBC; Female 4.8 m RBC Transports 97% of the oxygen throughout the body (3% dissolved in plasma). Oxygen saturation of hemoglobin is highest where concentration of oxygen is greatest. Oxygen binds to hemoglobin in oxygen- rich blood leaving the lungs and dissociates from hemoglobin in oxygen poor tissues. Intracellular fluid - fluid INSIDE the cell Extracellular fluid - fluid OUTSIDE the cell Interstitial fluid (IF) - fluid that surrounds the cell = Fluid in the tissues Intravascular (IV) - plasma in the blood vessels HYPERTONIC = "Enter the vessel from cells" = CELL SHRINK ISOTONIC = "stays where I put it" = CELL STAY HYPOTONIC = "go Out the vessel & in to cell" = CELL SWELL DONOR (^) RECIPIENT 0 0

A A

B B

AB AB HYPOTONK ISOTONIC HYPERTONIC

RESPIRATORY SYSTEM

Air gets into the body:

1. Air enters though nose or mouth
2. Then nose: cleans, warms, and moistens the incoming air and passes it through the Pharynx (throat) & Larynx (voice box)
3. Air enters trachea which has special flap called "Epiglottis" - covers trachea when swallowing & prevents food from going down to wrong pipe.
4. Trachea (Left and Right) these breakdown into smaller tubes known as "Bronchioles" then ends in a tiny sac called, "Alveolus" - enables lungs to have an enormous surface area.

Carbon Dioxide Transport:

Most of carbon dioxide enters red blood cells and combines with water to eventually form bicarbonate ions (HCO3): Inhalation (Inspiration) - process of taking in oxygen which involves the increase in volume of the lungs, allowing air to rush in. Air flow into the lungs, pressure inside the alveoli become lower than atmospheric pressure. ATMOSPHERIC PRESSURE >>> Exhalation (Expiration) - process of breathing out carbon dioxide out of the lungs. Pressure in the lungs is greater than the pressure of the atmosphere. LUNG PRESSURE >>> Chemoreceptors - controls respiratory rate (e.g. As blood pH decreases, chemoreceptors send nerve impulses to the diaphragm and intercostal muscles to increase respiratory rate). Help maintain homeostasis by responding to blood composition changes detect increase in blood pH.

• Trachea

o

& Alveolus/Alreoli O V Bronchioles

CO2 +^ H^

• (^) H2 (83 -r (^) H+ (^) HCO;

Inhalation

Exhalation Diaphragm contracts^ Diaphragm relaxes chestexpands chestcontracts Air (^) Flows in^ Air^ flows^ ort

Acetylcholine - example of a neurotransmitter. released from the end of an axon, when Ca2+ moves into the terminal end of the axon is picked up almost instantly by the dendrites of the next neuron can stimulate muscles to contract or inhibit postsynaptic potential is released between neurons in the parasympathetic system Acetylcholinesterase - enzyme that breaks down extra acetylcholine in the synaptic left. Norepinephrine - peptide neurotransmitter that is released between neurons within the central nervous system. GABA - neurotransmitter that is secreted in the central nervous system and acts as an inhibitor.

Parts of the Nervous system

1. Central Nervous System (CNS) - all neurons in the brain and spinal cord
2. Peripheral Nervous System (PNS) - neurons outside brain and spinal cord a. Somatic Nervous System - controls voluntary activities (e.g. movement of eyes across a page) b. Autonomic Nervous System - controls involuntary activities e.g. heartbeat, digestive system) i) Sympathetic nervous system - controls the "fight - or-flight" response ii) Parasympathetic nervous system- brings body back to homeostasis after a threat has passed.

Parts of the Brain

Cerebrum - 1) controls all voluntary activities; receives and interprets sensory information; largest part of human brain 2) consists of outer gray matter (cerebral Cortex) and inner white matter. 3) corpus callous - thick band of nerve fibers of white matter that enables the right and left side of the cerebral hemispheres to communicate. Language, communication, learning & memory Cerebellum - coordinates muscle activity, refinement of movement Hypothalamus - regulates homeostasis; secretes hormones; regulates pituitary gland Medulla - controls involuntary actions (e.g breathing, swallowing, heart beat, respiration) Pons - connects parts of the brain with one another and contains respiratory center Midbrain - center for visual and auditory reflexes Thalamus - main sensory relay center for conducting information between the spiral cord and cerebrum. Superior Pons establishes regularity of respiration

Thalamus

Cerebrum

midbrain

Hypothalamus

Pons

Medulla

cerebellom

DIGESTIVE SYSTEM

INTRACELLULAR DIGESTION - digestion in simple animals which occurs within food vacuoles in simple animals. EXTRACELLULAR DIGESTION - digestion in more complex animals which occurs within a digestive tract. (zoo)

DIGESTIVE SYSTEM (Human)

consists of the mouth, esophagus, stomach, small intestine, large intestine, and accessory organs (liver, pancreas, gall bladder, and salivary glands). 4 Groups of Molecules broken down by the Digestive tract: Sugars Proteins Fats Nucleic acids Mouth - aka "oral cavity" where digestion begins with alpha-amylase which is in saliva and digests carbohydrates Mechanical digestion - chewing, softening, and breaking up food Saliva - secreted by the salivary glands, contains an important enzyme known as Salivary amylase that facilitates breakdown of starch into maltose Bolus - chewed food shaped into a ball that moves through the pharynx and into the esophagus Peristalsis - waves of contraction that push the food through the esophagus toward the stomach Stomach - thick, muscular sac that temporarily stores the ingested food, partially digests protein, and kills bacteria. Gastric juices - contain digestive enzymes and hydrochloric acid (HCl) Pepsin - breaks down proteins into smaller peptides HCl - kills most bacteria Mucus - protects the stomach lining from the acidic juices Chyme - partially digested food by the churning action of the stomach Small intestine - all food stuffs are completely digested by peptidases for proteins and maltase, lactase, and sucrase for carbohydrates. 90% of absorption and digestion occurs here 3 Regions: duodenum, jejunum, ileum chyme moves into the first region, duodenum, through the pyloric sphincter Villi and Microvilli - these are folds that increase the surface area of the small intestine for food absorption. lacteals are lymph vessels that absorb fatty acids within each villus. Pancreas - secretes a number of enzymes into the small intestine through the pancreatic duct. Trypsin & Chymotrypsin - break down proteins to dipeptides Pancreatic lipase - breaks down lipids into fatty acids and glycerol Pancreatic amylase - breaks down starch into disaccharides Ribonuclease & Dexoyribonuclease - break down nucleic acids into nucleotide Bile - acts as an emulsifier which mechanically breaks up fats into smaller fat droplets; made in the liver and stored in the gall bladder Large intestine - reabsorbs water and salts Harbors harmless bacteria that break down undigested food and in the process provide certain essential such as Vitamin K. Feces - leftover undigested food that moves out of the large intestine through the rectum. SPFN Drodenum jejunum Ilerm

***addition

A. ANTERIOR PITUITARY

1. Follicle-stimulating: follicle maturation; spermatogenesis
2. Luteinizing: ovulation; testosterone synthesis
3. Adrenocorticotropic (ACTH): stimulate adrenal cortex to make/secrete glucocorticoids
4. Thyroid: stimulates thyroid to make hormones
5. Prolactin: stimulate milk production
6. Endorphins: inhibit perception of pain
7. Growth hormone: bone/muscle growth

B. HYPOTHALAMUS (store in Posterior pituitary)

1. Oxytocin: uterine contraction & milk secretion
2. Vasopressin (ADH): water reabsorption in kidneys

c. THYROID

1. T3 & T4: metabolic activity
2. Calcitonin: decrease blood calcium level

D. PARATHYROID

1. Increase blood calcium level

E. ADRENAL CORTEX

1. Glucocorticoids: increase blood glucose level & decrease protein synthesis
2. Mineralocorticoids: increase water reabsorption in kidneys

F. ADRENAL MEDULLA

1. Epinephrine/ Norepi: increase blood glucose level & heart rate

G. PANCREAS

1. Glucagon: convert glycogen to glucose in liver and increase blood glucose
2. Insulin: lowers blood glucose, increase glycogen stores
3. Somatostatin: suppers secretion of glucagon and insulin

EXCRETORY SYSTEM

Kidney - major organ that regulates excretion in humans; each kidney is made up of a million nephrons Nephrons - functional units of the kidney, consists of: a. Bowman's Capsule - found in the renal cortex (outermost section) b. Proximal Convoluted Tubule - found in the renal cortex c. Loop of Henle - found in the renal medulla (inner section) d. Distal Convoluted Tubule - found in the renal medulla e. Collecting Duct How a Nephron Works: Blood enters nephron at Bowman's capsule Renal artery leads to kidney and branches into arterioles, then tiny capillaries Glomerulus - ball of capillaries that "sits" within a Bowman's capsule Blood is filtered as it passes through glomerulus Plasma is forced out of capillaries. Plasma is now called a Filtrate. From Bowman's capsule, filtrate passes through the proximal convoluted tubule, then loop of Henle, then the distal convoluted tubule, and finally the collecting duct. As it travels along the tube, fitratei s modified to form urine. Concentrated urine moves from collecting ducts to ureters, then into bladder, and finally out through urethra Hormones of the Kidney 2 Hormones regulate the concentration of water and salt in the kidneys: Vasopressin - or antidiuretic hormone; allows water to be reabsorbed from collecting duct; controls volume of urine Low fluid intake: ADH concentrates urine High fluid intake: ADH levels wil be low; dilutes urine Aldosterone - regulate sodium reabsorption at the distal convoluted tubule How urine is made = Filtration - blood is filtered as it passes through glomerulus to Bowman's capsule Reabsorption - as filtrate moves through the proximal convoluted tubule, some materials are reabsorbed; small solutes leave proximal convoluted tubule and are reabsorbed by peritubular capillaries; remaining material in tubule is urine Secretion - as filtrate moves through convoluted tubules, some substances are secreted from surrounding capillaries into the tubule. 1 2 3 4

GLOMERULAR

FILTRATION

TUBULAR

REABSORPTION

TUBULAR

SECRETION

URINE

EXCRETION

Blood flows into the kidneys: 1,200 mL/ min. Filters water, electrolytes, & small molecules into the glomerulus (large molecules stay in the bloodstream). Fluid moves from renal tables into the capillaries. They reabsorb fluid into the venous circulation. Fluid moves from the capillaries into the renal tubules to get excreted. Adults should void 1-2 L/day. No less than 30 mL/ hr.

GAMETOGENESIS production of gametes OOGENESIS Production of ova Begins during embryonic development Follicle cells provide nourishment and protection to the ovum Oocyte that has certain levels of follicle stimulating hormone can be ovulated. Other socytes will undergo "Atresia", a programmed cell death. SPERMATOGENESIS Production of spermatozoa (sperm cells) Begins at puberty Sertoli cells provide nourishment to the developing sperm Each primary spermatocyte divides into four spermatozoa

EMBRYONIC DEVELOPMENT

1 Fertilization Union of sperm & ovum Sperm secretes protein that ovum recognizes thus ensuring fertilization of same species takes place Occurs in uterine (fallopian) tube w/in 12 - 24 hrs after ovulation Fashion of nuclei & DNA replication occurs Sperm can remain viable for abt (^48) hrs after deposition in the vagina. Zygote rapidly divides w/o getting bigger into a solid ball of cells called "Morula." 1st division of zygote begins abt 24 hrs after fertilization and be completed abt 6 hrs later. 2 CLEAVAGE 3 BLASTULA Cell divisions continue, pushing other cells to form a liquid-filled cavity called "Blastocoel" 4 gastrula Cell more inward to form 3 germ layers: Ectoderm, Mesoderm, & Endoderm Ectoderm - the epidermis, eyes, & nervous system. Mesoderm - the inner linings of digestive tract & respiratory tract. Also, the accessory organs ( pancreas, gallbladder, liver). And, muscle, skeleton, kidneys, & reproductive system Endoderm - endocrine glands, lungs 5 organogenesis Cell starts to differentiate. This stage begins with "Notochord." Above the notochord, neural plate indents to form neural groove, then continues to roll up into a cylinder, forming "Neural tube." Estrogen: maintains female secondary sexual characteristics. Progesterone: promotes growth/ maintenance of endometrium. r

CELLS

MITOCHONDRIA - functions in cell respiration where ATP is produced ENDOPLASMIC RETICULUM - network of membranous sacs & tubes Rough ER - contain many membrane-bound besides called Ribosomes, responsible for protein synthesis, folding, and dispatch. Smooth ER - does not have ribosomes, responsible for synthesis of lipids and some steroid hormones. Ribosome: as stated above, they function in protein synthesis, may be free-floating or embedded in endoplasmic reticulum Golgi apparatus: involved in synthesis, sorting, modification, and secretion of cell products Lysosome: secretes digestive enzymes Peroxisome: produces hydrogen peroxide as a by product of other metabolic reactions and converts it to water. Cytoskeleton: reinforces cell shape and functions in cell movement Microfilaments Intermediate filaments Microtubules Centrosome: region where the cell's microtubules are initiated Cilia & Flagella: motile appendages containing microtubules as well as the protein dynein Cell wall: maintains cell shape, protects cell damage, functions in cell communication Composed primarily of cellulose (in plants) or chitin (fungi) NOT PRESENT in animal cells Vacuole: for storage, break down of wastes hydrolysis of macromolecules in plants NOT PRESENT in animal cells Plasmodesmata: channels in cell walls that connect the cytoplasms of adjacent cells; function in cell communication NOT PRESENT in animal cells Photosynthesis: "synthesis using light" (6CO2 + 6H20 à C6H1206 + 6O2) Chloroplasts: contain specialized light - absorbing pigments (chlorophylls) Thylakoid: location of thylakoid reaction Light: chemical energy Photosynthesis pigment: absorption of energy of sunlight Chlorophyll a and b: abundant in green plants: differ in side chain (-CH3 in a, -CHO in b) Carotenoids: considered accessory pigments because light energy from them is transferred to chlorophylls CELL WALLS & VACUOLE & plasdomesmata IN ANIMAL CELLS

THE CELL CYCLE

CELL DIVISION

MITOSIS - division of a cell's nucleus into 2 new nuclei.

1. Prophase - nucleoli disappear, chromatin fibers condense into chromosomes.
2. Prometaphase - nuclear envelope fragments, chromatids now each have a kinetochore.
3. Metaphase - chromosomes convene at metaphase plate; for each chromosome kinetochores of sister chromatids are attached to kinetochore at opposite poles.
4. Anaphase - sister chromatids separate, becoming full-fledged chromosomes and being moving towards opposite ends of the cell.
5. Telophase - 2 daughter nuclei form, nuclear envelope reforms, nucleoli reappear, chromosomes decondense. Cytokinesis - division of cytoplasm in animal mitosis usually coincides withtelophase. Cell plate formation - future cell wall dividing the daughter cells in plant mitosis.

another definition by: G.G ALVERO MITOSIS - nuclear division with genetic change a. Prophase - : condensation of chromatin into chromosomes Centrioles move to opposite ends of cells Nucleolus and nucleus disappear Spindle apparatus forms b. Metaphase - chromosome align at equator C. Anaphase - sister chromatids split and more toward opposite ends of cells D. Telophase - nuclear membrane reforms the nucleolus e. RESULT - 2 identical daughter cells MEIOSIS - double nuclear division which produces 4 haploid gametes a. In HUMANS - only spermatogonium and organism undergo meiosis b. Prophase I - homologous chromosomes line up along side each other, matching their genus exactly. May exchange DNA sequences. c. Metaphase I - homologous move to metaphase plate, do not separate d. Anaphase I - homologous separate e. Telophase I - nuclear membrane may or may not form. If cytokines occurs, the cells are haploid with 23 chromosomes CELL LIFE CYCLE a. G1 - usually the longest stage. Cell splits and grows. b. S - energy used for replicating DNA c. G2 - cell prepares to divide d. M - meiosis or mitosis e. C - cytokinesis - separation of the cellular cytoplasm due to constriction of microfilaments about the center of the cell. MITOSIS MEIOSIS

undergoes only^ ONEdivision^ undergoes^

TWO divisions

two daughter alls per division^ (daughter alls^ atthe^

end (^) of the second division produces (^2) genetically identical^ daughterproduces^ of (^) genetically (^) differentcalls^ from cells each^ other^ and^ from the^ parent well number (^) ofchromosome^ ofdaughter cell^ number (^) ofchromosome (^) ofdaughtercul is same as^ the^ parent cell^ (b=P) (^) is (^) halitas theparentcell

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occurs in^ somatic^ cells^ occurs in sex alls^ or^ germ^ cells

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reproduction perpetration^ ofspecies^ &^ genetic^ diversity

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ECOLOGY

ECOLOGY The hierarchy within the biosphere: a. Individual b. Population - group of individuals belonging to the same species living in a certain place at a certain time c. Community- refers to the group of population of species interacting with each other d. Ecosystem - refers to the ecological community together with all the abiotic factors present that affects and influences the community e. Landscape - refers to the flow of materials, energy and organisms between two ecosystems f. Region - a broad geographic area distinguished by similar features that supports life g. Biosphere - highest form of ecological organization which refers to all the life forms and factors that affect and influences these life forms study of interactions among organisms and their environment PLANT

BIOME DISTRIBUTON^ PRECIPITATON^ TEMP^ ADAPIMON

Tropical Equatorial A (^) tropical rain

25-29 vertically layered,

Forest (^) subequatorial Forest,^ relatively^ mostintense^ compet

regions

constant about tition^ oflightamong

200-400 cm^ annually, plants,^ more strat

tifications

in rain Tropical dry^ Forests:^ Forests/broadleaf highly

seasonal,

evergreen leaves,

150-200 cm^ annually^ Forest

trees (^) drop leaves (^) during dry dry season,^ for^ season, abundance

6-7 months^ ofepiphytes.

Desertoccurs^ in^ a^ less^ than^ 50 during water storage band (^) near 30050 cm (^) annually the (^) day of^ in succulentplants,

deep roots,^

reduced North and^ -^ 30%^ during leapsurface^ area, South latitude^ the^ night exhibits C

cam photosynthesis

Savanna

Equatorial and Seasonal (^) rainfall 24°c-290 presence (^) ofthorns, subequatorial averaging 30-50 cm^ small leaves (^) for regions

annually, dry season^ thedry condition

lastsup to^ 8-

months