Human Biology Study Notes PDF

**Scientific Method** **Define science:** a systematic process for learning about the world and testing our understanding of it. **What is deductive and inductive reasoning? Deductive:** Applies general principles to predict specific results. **Inductive:** uses specific observations to construct...

**Scientific Method** **Define science:** a systematic process for learning about the world and testing our understanding of it. **What is deductive and inductive reasoning? Deductive:** Applies general principles to predict specific results. **Inductive:** uses specific observations to construct general scientific principles. **Describe the steps of the scientific method:** Assumptions \> Questions \> Hypothesis \> Predictions \> Test \> Results **What is a hypothesis?** A proposed explanation that makes testable predictions, needs to tell us something we want to know. **What is a theory?** A highly successful hypothesis, and that can be tested. **What makes a good hypothesis?** **Explain the different ways of testing hypotheses:** By an experiment, where it often involves manipulation of the independent and dependent. **Know the difference between a dependent and independent variable**: independent is the variable that is manipulated by the scientist and dependent is the one that depends on the other variables. **What is a Human?** **Learn the 5 characteristics of a living thing:** **Identify the evolutionary relationship between humans and other living things.** **Organisation of the Human Body** ***Define biology: The science of living things. Anatomy: The study of the structure and the shape of the body and their relationship with one another. & physiology: Science that studies body function.*** ***Explain how anatomy and physiology are related: Those are the subdivisions of the body that describe how our bodies are put together and how they work. The anatomy studies the structure, and the physiology studies the function.*** ***Learn the six levels of organization of the human body and provide examples of how bodily processes interact with each other at different levels to maintain life.*** - ***Chemical: is composed by atoms (smallest components of molecules) and molecules (made up of atoms) (non-living)*** - ***Cellular: smallest unit of living things, made up of many kinds of molecules, some structural, most involved in reactions within cells*** - ***Tissue: aggregations of similar cells and the surrounding area arranged and ordered to perform a specific function*** - ***Organ: two or more groups of different tissues, anatomically distinct, perform a specific physiological function. Example: stomach, muscle cells do mechanical digestion.*** - ***Organ system: group of organs working together, and some contribute to multiple organ systems. Example: digestive system*** ***Understand what an emergent property is: (all organs work together) a property that isn't evident in the individual components of a system, but show up when combining those components. Chemical level made of atoms (non living) \> living atoms start to form (cells)\> creates tissues, ex: m uscles\> cells allow muscles to contract which shows organs can work too, ex: heart pumping blood thanks to contractions\> organ system, since your it fully functions you can live\> full on organism,*** ***Learn names of body cavities (be specific) and how they are related to one another. Be able to assign different organs to each cavity. For dorsal cavity \> Cranial cavity (skull), spinal cavity (vertebral column). For ventral cavity \> thoracic cavity (lungs). For abdominopelvic cavity \> abdominal cavity (liver, stomach), pelvic cavity (bladder).*** ***Recognise anatomical names of body parts and assign a simple function to body parts.*** ***Learn 11 organ systems, what they do (brief function), and how they relate to each other. Identify and classify by organ system all organs discussed in class and in the lab.*** - ***Integumentary: skin and structures associated with it, ex: hair, sweat. It controls body temperature, protects the body from environmental hazards*** - ***Skeletal: bones, joints and associated cartilage, ligaments. It supports and protects the body, forms blood cells*** - ***Muscular: skeletal muscle, tendons. It enables movements and maintains posture*** - ***Nervous: special sense organs such as eyes, brain spinal cord. It detects stimuli, coordinates activities, stores memory*** - ***Endocrine: all glands that produce hormones. It secretes hormones, regulates body activities*** - ***Cardiovascular: heart, blood vessels such as veins and arteries. It delivers oxygen, cells and nutrients to the body*** - ***Lymphatic: cells that carry out immune responses. It returns proteins and fluid to blood and defends against infections and disease*** - ***Respiratory: air passageways such as trachea, bronchial tubes. It helps regulate the acidity of body fluids*** - ***Digestive: organs of the gastrointestinal tract such as mouth, stomach small and large intestine. It absorbs nutrients*** - ***Urinary: kidneys, urinary bladder. It controls water balance PH*** - ***Reproductive: gonads (male testes, female ovaries), mammary glands for females. It produces mammary glands milk, gonads produce gametes (sperm)*** ***Define the directional terms used to locate parts of the human body.*** - ***Superior: towards de head (above)*** - ***Inferior: away from the head (below)*** - ***Anterior: towards the front of the body*** - ***Posterior: towards the back of the body*** - ***Medial: towards the middle*** - ***Lateral: away from the middle*** - ***Proximal: close the attachment point*** - ***Distal: far from the attachment point*** - ***Superficial: towards the surface of the body*** - ***Deep: internal*** ***Describe the anatomical position: bilateral symmetry, means right and left sides of the body are mirror images (for humans), remarkable correspondence of size and shape between body parts on opposite sides of the body.*** ***Use correct anatomical terms to describe body directions and body plains or sections.*** The nose is SUPERIOR to the mouth The nose is INFERIOR to the eyes The breastbones are ANTERIOR to the spine The spine is POSTERIOR to the breastbone The heart is MEDIAL to the arms (cos heart closer to the middle) The stomach is MEDIAL to the shoulders The arms are LATERAL to the heart The toes are DISTAL to the knee (cos farther away from attachment point) The elbow is PROXIMAL to the shoulder The brain is DEEP to the skull ***Know the names of the planes through which cross-sections of the body and organs can be made*** - ***Sagittal plane: cuts whole body in the middle having left and right cut into a mirror way*** - ***Frontal plane: (coronal) divides the body in half from anterior and posterior portions from head to toe*** - ***Transverse plane: divides the body in the middle, showing upper half and bottom half*** **Homeostasis** **Define metabolism:** a product of chemical reactions that occur in body cells that uses and releases energy. **Catabolism:** breaks down substances into their simpler building rocks, which releases energy**. Anabolism:** synthetizing more complex cellular structures from simpler substances but requires energy. **Explain what the interstitial fluid is:** Fluid found in the spaces around cells. It comes from substances that leak out of blood capillaries (the smallest type of blood vessel). It helps bring oxygen and nutrients to cells and to remove waste products from them. **Define homeostasis:** the maintenance of a state of dynamic equilibrium around a certain set point within the normal range for various physical or chemical factors, ex: body temperature, blood sugar, oxygen **Explain why homeostasis is necessary for human survival:** it ensures that the body's internal environment remains steady despite changes inside and outside the body **Describe the components of a feedback system.** - **Receptor (sensor):** monitors changes in a controlled condition and sends nerve impulses or chemical signs to the control center. - **Control center:** sets the range of values within which a controlled condition should be maintained, evaluates the input from the receptors and generates output commands**.** - **Effector:** body structure that receives output from the control center, produces a response changes the controlled condition, most tissues/organs can be effectors **Define a negative feedback system:** this system reverse a change in the controlled variable, bringing it back to normal, it tends to regulate conditions in the body that are held stable such as blood pressure, body temperature and glucose levels. High body temperature\> results in sweating\> lower body temp **Define a positive feedback system:** these systems strengthen a change and must be shut down by an outside force , tend to reinforce conditions that don't happen very often like systems that control blood clotting, and it must shut off by some event outside the system if not it can produce life threatening changes in the body. Contractions\> result in more oxytocin release\> more contractions **Know the examples of the various feedback systems described in lecture** **Terminology to know:** - **feedback system:** cycle of events in which a condition in the body is continually monitored, evaluated, re-monitored - **controlled condition:** ex: blood sugar level - **normal range:** a restricted set of values that is healthy and stable - **set rate:** the value around which the normal range fluctuates - **stimulus:** disruption that causes a change in the controlled condition **Provide & explain different examples of feedback systems.** **Understand the relationship between a disruption in homeostasis:** abnormality of structure and/or function, slight moderate homeostatic imbalance **and disease:** specific term for illness characterized by a set of symptoms and signs, many due to a moderate homeostatic imbalance, ex: diabetes **Define:** - **pathophysiology:** the organised study of the underlying physiological processes associated with disease - **signs:** objective abnormalities that can be seen or measured by someone other than the patient - **symptoms:** subjective abnormalities felt by the patient - **acute:** diseases of short duration - **chronic:** diseases that develop slowly and last a long time **The Cell** **Name and describe the three main parts of a cell.** - **Plasma membrane:** outer surface, separates the inside of the cell from the outside, and regulates what comes in and out - **Cytoplasm:** the insides of the cell (not including the nucleus) made of two components, **cytosol:** liquid portion of the cell and **organelles:** machinery of the cell - **Nucleus:** largest organelle of the cell, control center that contains DNA **Identify on a diagram and provide the function for the following: nucleus, nucleolus, rough and smooth endoplasmic reticulum, ribosome, golgi apparatus, mitochondria, lysosome, perioxisome, cytoskeleton, centrosome, cillia, microvilli, flagella, cell membrane.** **Know which organelles have a membrane:** mitochondria, nucleus, lysosomes, peroxisomes, Golgi apparatus, endoplasmic reticulum **Understand the basic steps of making a protein:** genes tell the body which amino acids must be put together to make a protein, and is specifically designed to carry out a single body function with transcription and translation **Define:** - **DNA:** hereditary material codes for proteins - **Chromatin:** a more extended form of DNA, allows to direct cell day to day operations - **Chromosomes:** more condensed than chromatin, form only for cell division, humans have 46 chromosomes - **Genes:** the basic physical and functional unit of heredity - **ATP:** adenosine triphosphate, is the source of energy for use and storage at the cellular level **Describe the composition of the plasma membrane and relate it to membrane functions:** lipids (phospholipids and cholesterol), proteins, and carbohydrates**.** The chemical structure of the cell membrane makes it remarkably flexible, the ideal boundary for rapidly growing and dividing cells. **Understand the basic steps of cellular respiration** **Cell Membrane Transport** **Understand what can and cannot pass through the plasma membrane:** small uncharged polar molecules, such as H~2~O, also can diffuse through membranes, and lipids such as hydrocarbons, but larger uncharged polar molecules, such as glucose, and ions cannot **Define selective permeability:** determines which substances can enter or leave cytoplasm **Define a concentration gradient:** is where concentration of a substance is greater in one location than another **Describe the processes that transport substances across the plasma membrane:** passive mechanisms, no energy required to move along concentration gradient (high moves towards low) **Define and describe the differences among:** - **simple diffusion:** molecules pass through the plasma membrane following their concentration gradient (high to low) - **facilitated diffusion (both channel- and carrier-mediated passive transport):** ions and larger molecules too big to squeeze between phospholipid molecules require a special transport protein to transport them through, only specific molecules are able to traverse a given channel - **osmosis:** deals with the movement of water into and out of cells - **active transport:** cells would be unable to maintain proper concentrations of solutes necessary for proper function - **solute pumping:** solutes are transported across plasma membranes with the use of energy from an area of lower concentration to an area of higher concentration (low to high concentration) - **endocytosis:** plasma membrane surrounds material - **exocytosis:** cells discharges materials - **phagocytosis:** cell eating (large particles) - **pinocytosis:** cell drinking (tiny particles/molecules) **Understand the functioning of the sodium / potassium pump:** moves things into the opposite direction **Differentiate between isotonic:** cells maintain their shape and function, normal state. **Hypertonic:** water rushes out, becomes dehydrated and shrivels up. **and hypotonic solutions:** water rushes in, about to pop since its filled with water. **Tissues** **Define Histology:** the study of tissues **Describe the characteristics of the 4 basic types of tissues:** - **Epithelial tissue:** covers outside of body, line organs, and cavities. Closely packed cells with little extracellular material between them - **Connective tissue:** most abundant tissue type, typically found between other tissues - **Muscle tissue:** consist of long cells called muscle fibers, which contract in response to nerve signals - **Nervous tissue:** specialized to conduct electrical impulses from one region of the body to another **Give the chief locations of the various tissue types in the body** - **Epithelial tissue:** skin, lining of digestive tract, respiratory system, and glands - **Connective tissue:** bone, blood, cartilage, tendons, and fat - **Muscle tissue:** skeletal muscles, heart (cardiac muscle), and walls of hollow organs (smooth muscle) - **Nervous tissue:** brain, spinal cord, and nerves **Define the extracellular matrix:** is a network of external proteins and chemicals that gives surrounding tissues structural and metabolic support. **Differentiate between the two major types of epithelia:** - **Epithelia:** Protects and lines body surfaces and cavities (e.g., skin, digestive tract). - **Glands:** Forms glands that secrete hormones or other substances (e.g., sweat glands, endocrine glands). **Discuss the general features of epithelial tissue (5) including cell shapes (squamous, cuboidal, columnar) and arrangement of layers (simple stratified) and their functions and locations in the human body** - **General features:** - Closely packed cells with the extracellular material between them - Epithelial cells have an apical and basal surface - Epithelial cells are vascular - Epithelia have nerve supply - Epithelia have a high capacity for cell division - **Cell shapes:** - Squamous, flat and thin (squished) - Cuboidal, cube shaped - Columnar, are taller than they are wide - **Layers:** - Simple epithelium is one layer of cells - Stratified epithelium has several layers of cells - **Functions:** - Provide physical protection, from abrasions dehydration or destruction by chemical or biological agents - Control permeability, capable of selective absorption or secretion - Provide sensation, can detect changes in the environment; ex: touch receptors - Produce specialized secretions, glandular epithelial cells produce secretions **Differentiate between the two main types of glands (endocrine glands & exocrine glands) and provide examples of each** - **Endocrine glands**: secrete hormones directly into the bloodstream, ex: thyroid, adrenal glands - **Exocrine glands**: release substances through ducts to external surfaces or cavities, ex: sweat glands, salivary glands **Describe the three main types of fibers (collagenous, reticular and elastic) in connective tissue and their functions:** - Collagenous fibers provide strength and flexibility (made of collagen) - Reticular fibers join connective tissue to adjacent tissues (made of collagen) - Elastic fibers stretch and snap back to their original length ( made of elastin) **Describe the structure and function of various types of connective tissue:** - **adipose connective tissue:** specialized connective tissue in storing fat in dispose cells scattered within the matrix**,** function: major energy reserve - **areolar:** most widely distributed connective tissue in the body, consists in fibers and several type of cells - **dense:** it is like this because of tight weave of collagen fibers in parallel bundles, and maximizes tensile strength (resists pulling without breaking)**,** common in tendons and ligaments - **cartilage:** dense network of collagen and elastic fibers embedded in chondroitin sulfate, stronger than dense fibrous connective tissues, and does regenerate very easily - **bone:** organs composed of several different connective tissues including bone tissue, forms most of the skeleton, and supports, protects, and allows movements - **blood:** liquid extracellular matrix is the plasma (water, salts, and dissolved proteins), red and white blood cells & platelets. Function: transportation, regulation, and protection **Differentiate between tendons:** attach muscles to bones, **and ligaments:** joins bones together at joints **Identify components of blood:** plasma (55%), soluble materials (mostly water), which is lighter so it stays at the top of the tube, and formed elements (45%), cells and cell fragments, which is heavier which stays at the bottom of the tube **Name three types of muscle tissue and explain their different functions** - **skeletal:** voluntary movement, attached to bones by tendons, made of numerous muscle cells called muscle fibers - **smooth:** involuntary body activities (autonomous), found in walls of bladder and arteries - **cardiac:** contraction of the heart, found in the contractile wall of the heart **Provide the function of nervous tissue and the two main types of cells** - **neurons:** convert stimuli into serve impulses and conduct them - **neuroglia:** do not generate nerve impulses, but serve supportive function **In class question examples** **What is true about vasoconstriction:** blood moves away from the surface to the skin, it happens first in your finger and your toes, it is a response to your internal temperature dropping below the set point, it constricts the blood vessels in your skin **What is a serous cavity:** a space between 2 serous membranes that surround some of the organs **What cavities will a surgeon have to cut through to reach the heart:** the mediastinum, the pericardial cavity, and the thoracic cavity **Which organelles have double membranes:** the nucleus and the mitochondria **Where would you find** - **Epithelia:** lining the stomach - **Glandular epithelial tissue:** in the pancreas - **Skeletal muscle tissue:** expanding and contracting - **Adipose tissue:** in the subcutaneous layer - **Dense connective tissue:** connecting the muscle to the bone - **Neuroglia:** next to the neurons Cell Organelles - Types, Structure and their Functions