BIO 110 --> Exam 2

Human Muscular System

  1. Mechanisms and structures that allow sliding mechanisms to function within the muscle cell

    1. Actin filaments = thin filaments that provide site for myosin attachment

    2. Myosin filaments = thick filaments with heads that bind to actin

    3. Troponin and tropomyosin = regulatory proteins that control interaction between actin and myosin 

  2. What causes action potential within motor neuron

    1. Threshold stimulus = depolarizing stimulus that reaches certain threshold

    2. Sodium ion influx = voltage-gated sodium channels open allowing Na+ ions to enter which depolarizes the neuron

  3. Mechanism that causes electrical impulses within a muscle unit

    1. Motor neuron activation = motor neuron releases acetylcholine at neuromuscular junction

    2. Action potential propagation = acetylcholine binds to receptors on muscle cell membrane leading to action potential that travels along sarcolemma and down T-tubules 

  4. Identify each structure from a muscle unit

    1. Muscle fiber = basic cellular unit of a muscle

    2. Fascicles = bundles of muscle fibers

    3. Tendon = connects muscle to bone

    4. Sarcomere = functional unit of muscle contraction 

  5. Understand substructures of sarcmere and their function

    1. Z-lines = define the boundaries of each sarcomere

    2. A-band = contains myosin filaments and overlaps with actin

    3. I-band = contains only actin filaments

    4. H-zone = area where only myosin is present 

  6. How most human body heat is generated and what system accounts for this

    1. Muscle contraction = muscle activity generates heat as a byproduct 

    2. Metabolic processes = metabolism of nutrients through muscular and endocrine system

  7. Identify major human muscle groups 

    1. Upper body = deltoids, pectorals, biceps, triceps

    2. Core = obliques, erector spinae

    3. Lower body = quadriceps, hamstrings, gluteals, calves

  8. Understand order of events that lead to successful muscle contraction after the initiation by nerve impulse

    1. 1 = nerve impulse → motor neuron fires releasing ACh

    2. 2 = action potential → ACh binding causes depolarization and action potential generation

    3. 3 = calcium release → action potential travels to sarcoplasmic reticulum triggering Ca2+ release

    4. 4 = cross-bridge cycling → calcium binds to troponin moving tropomyosin and allowing myosin heads to bind to actin

    5. 5 = contraction → myosin pulls actin filaments shortening sarcomere 

  9. How electrical impulses cause certain molecules to be released and how particular cell structures release these molecules 

    1. Electrical impulses trigger opening of calcium channels and influx of calcium ions stimulate the release of neurotransmitters from synaptic vesicles in neuron

    2. Synaptic vesicles = store neurotransmitters

    3. Calcium channels = open in response to action potentials allowing Ca2+ influx

    4. Plasma membrane = fuses with vesicles to release neurotransmitters into synaptic cleft 

  10. Identify muscles that section particular human body cavities

    1. Diaphragm = separates thoracic and abdominal cavities

    2. Abdominal muscles = rectus abdominis → help partition the abdominal cavity 

  11. Isotonic contractions vs. isometric contractions → what each type of contraction produces and why

    1. Isotonic contractions = muscle changes length while contracting

      1. produce movement and work → resulting in joint motion

    2. Isometric contractions = muscle length remains the same while tension increases

      1. maintain posture and stabilize joints → without movement 

  12. Function of the sarcomere

    1. Basic contractile unit of muscle → responsible for the process of muscle contraction through interaction of actin and myosin filaments

  13. Actin and myosin filaments and their functions 

    1. Actin = provides framework for muscle contraction → interacts with myosin to generate force

    2. Myosin = has heads that bind to actin and pull it causing contractions through hydrolysis of ATP

Human Respiratory System

  1. Why breathing is significant for humans

    1. Essential to bring in oxygen and release CO2 → vital to maintain homeostasis

  2. How oxygen rich blood flows throughout the heart 

    1. Pulonary veun = bring oxygenated blood from lungs to left atrium

    2. Left atrium = blood flows into left atrium and it pumped into left ventricle

    3. Left ventricle = contacts to send blood into aorta → distributing it throughout body 

  3. How blood flows through regions within the human heart 

    1. Right atrium = receives deoxygenated blood from body

    2. Right ventricle = pumps blood into lungs via pulmonary artery for oxygenation

    3. Lungs = blood get oxygenated and releases CO2

    4. Left atrium = receives oxygen-rich blood from lungs via pulmonary veins

    5. Left ventricle = pumps oxygenatd blood into aorta for systemic circulation

  4. Function of each structure of upper respiratory system 

    1. Nasal cavities = filters, warms and humidifies air

    2. Pharynx = passageway for air and food 

    3. Larynx = houses vocal cords and protects trachea against food aspiration

    4. Trachea = conducts air to bronchi and filters marticles

  5. Function of each structure of lower respiratory system

    1. Bronchi = conducts air ino lungs → branches into smaller bronchi and bronchioles

    2. Bronchioles = smaller airways that lead to alveoli → regulate airflow

    3. Alveoli = tiny air sacs where gas exchange occurs 

  6. How pressure in lungs changes between inhalation and exhalation

    1. Inhalation = diaphragm and intercostal muscles contract, lung volume increases and pressure decreases

    2. Exhalation = muscles relax, decreased lung volume and increase pressure 

  7. Function of intercostal muscles and how do these muscles function during inhalation and exhalation

    1. External intercostals = elevate ribs during inhalation and expand chest cavity

      1. Contracts during inhalation 

    2. Internal intercostals = assist with forced exhalation by depressing ribs

  8. How mechanics occur during expiration

    1. Diaphragm and external interocstal muscles relax, volume of thoracic cavity decreases, increase in pressure that pushes air out of lungs 

  9. How mechanics occur during inspiration

    1. Diaphragm contracts and moves down while external intercostal muscles lift ribs, thoracic cavity volume increases, drop in pressure that brings in air 

  10. Respiratory diseases and disorders

    1. Asthma = airway becomes inflamed and narrow causing difficulty breathing

    2. Lung cancer = abnormal growth of cells in lungs

    3. Pneumonia = infection causing inflammation in alveoli leading to fluid accumulation

  11. Order in which oxygen-rich blood flows through the heart

    1. Pulmonary veins → left atrium → left ventricle → aorta → body tissues 


Human Digestive System

  1. Major structures of digestive system and functions

    1. Mouth = begins digestion through mechanical breakdown and enzymatic action 

    2. Esophagus = muscular tube that transports food from mouth to stomach via peristalsis

    3. Stomach = mixes food with gastric juices to form chyme → begins protein digestion

    4. Small intestine = composed of duodenum, jejunum, and ileum → primary site for nutrient absorptions and receives bile and pancreatic juice for further digestion 

    5. Large intestine = absorbs water and electrolytes, compacts waste into feces

    6. Anus = regulates expulsion of feces from body 

  2. Accessory organs and structures and functions

    1. Salivary glands = produce saliva to moisten food 

    2. Liver = produces bile and processes nutrients absorbed from small intestine

    3. Gallbladder = stores and concentrates bile → releases it into small intestine

    4. Pancreas = produces digestive enzymes and bicarbonate to neutralize stomach acid in small intestine

  3. Function of an enzyme during digestion and where are these produced

    1. Enzymes = speed up chemical reactions that break food into small pieces 

    2. Produced in salivary glands, pancreas and then into small intestine and stomach 

  4. Function of large surface area in digestion

    1. In the intestines and maximize nutrient absorption 

  5. Standard metabolic rate

    1. Rate of metabolism when an organism is at rest 

  6. Basal metabolic rate

    1. Energy expenditure of an individual at rest → necessary to maintain vital functions like breathing and circulation 

  7. How molecules are digested in the body and what structures

    1. Carbohydrates = digested by salivary amylase in mouth and pancreatic amylase in small intestine into simple sugars

    2. Proteins = break down pepsin in stomach and pancreatic proteases in small intestine into amino acids

    3. Fats = emulsified by bile and digested by lipase in pancreas into fatty acids and glycerol 

  8. Process of peristalsis 

    1. Wave like muscle contractions that move food throughout digestive tract 


Human Genetics and Inheritance 

  1. Genes  and how are they molecular constructed

    1. Segments of DNA that encode instructions for building proteins that determine traits and functions in organisms

    2. Made up of sequences of nucleotides → each gene has a specific sequence 

  2. Chromosomes and how do they tie into genes

    1. Structures made of DNA and proteins that organize and compact genetic material → humans have 23 pairs

    2. Each chromosome contains a gene

  3. Scientific study of genetics

    1. Branch of BIO that studies heredity, gene variation and molecular mechanisms of genes

  4. Genome 

    1. Complete set of organism’s genetic material including all of its genes

  5. How does inheritance occur for humans

    1. Through transmission of genes from parents to offspring via gametes 

  6. Homologous chromosomes

    1. Pairs of chromosomes that are similar in shape, size, and genetic content → carry the same genes but may have different alleles 

  7. Karyotype and function in regards to the number of human chromosomes

    1. Visual representation of individuals chromosomes 

    2. Shows number of chromosomes in cell and can reveal abnormalities 

  8. Dominant alleles

    1. Express trait even when only 1 copy is present → ex: in heterozygous genotype

  9. Recessive alleles

    1. Only expressed when 2 copies are present 

  10. How alleles display themselves as homozygous or heterozygous

    1. Homozygous = organism has 2 identical alleles for a gene → AA or aa

    2. Heterozygous = organism has 2 different alleles for a gene → Aa

  11. Law of segregation

    1. During formation of gametes 2 alleles for a gene separate so that each gamete carries only 1 allele 

  12. Law of independent assortment 

    1. Genes for different traits assort independently of one another during gamete formation leading to genetic variation

  13. Incomplete dominance

    1. Phenotype of heterozygotes is intermediate between phenotypes of 2 homozygotes 

  14. Polygenic inheritance

    1. Multiple genes influencing a trait leading to a range of phenotypes → skin color, height

  15. How environment impacts phenotypic expression

    1. Nutrition, climate and lifestyle can affect traits like height and weight 

  16. Linked genes

    1. Located close to each other on the same chromosome and tend to be inherited together

  17. Sex-linked genes 

    1. Located on sex chromosomes and may exhibit different inheritance patterns in males and females 

  18. Nondisjunction

    1. Failure of chromosomes to separate properly during meiosis leading to gametes with abnormal chromosome numbers