hba notes - studentvip
TRANSCRIPT
HBA Notes
Topics Covered:
Week 1: Introduction to the Human Body
Week 2: Cell Structure and Function
Week 3: Movement of Molecules
Week 4: Nervous System
Week 5: Homeostasis and Endocrine
Week 6: The Heart
Week 7: Cardiovascular System
Week 8: Respiratory System
Week 9: Digestion and Metabolism
Week 10: Renal System
Week 11: Reproductive System and Acid-Base
Week 1: Introduction to the Human Body
Textbook readings: 2-5, 17-20 up to medical imaging, homeostasis 8-12
Learning Objectives:
1. Define anatomy and physiology
2. List the different levels of structural organisation in the body
3. Briefly describe the major functions of the major organ systems
4. List the major body cavities and their subdivisions
5. List the major classes of organic molecules in the body and provide a brief description of
their functions
6. Define homeostasis and describe the importance of homeostasis
Anatomy: The science of body structures and the relationships among them (first studied by
dissection)
Chemical Level: (letters of the alphabet)
- Includes atoms (the smallest units of matter that participate in chemical reactions) and
molecules (2 or more atoms joined together)
- E.g. DNA and glucose (commonly known as blood sugar)
Cellular Level: (words)
- Molecules combine to form cells, the basic structural and functional units of an organism
- Cells are the smallest living units in the human body
Tissue Level: (sentences)
- Tissues are groups of cells and the materials surrounding them that work together to
perform a particular function
4 Basic Types of Tissues in Human Body:
1. Epithelial tissue (covers body surfaces, lines hollow organs and cavities, forms glands)
2. Connective tissue (connects, supports, and protects body organs while distributing blood
vessels to other tissues)
3. Muscular tissue (contracts to make body parts move and generates heat)
4. Nervous tissue (carries information from one part of the body to another through nerve
impulses)
Organ Level: (paragraphs)
- At the organ level different types of tissues are joined together
- Organs are structures that are composed of 2 or more different types of tissues
- E.g. skin, bones
System Level: (chapter)
- A system consists of related organs (paragraphs) with a common function
- Sometimes an organ is part of more than one system (e.g. Pancreas: digestive and endocrine
systems)
Organismal Level: (book)
- Any living individual
- All the parts of the human body functioning together make up the total organism
Functions of Major Organ Systems:
Integumentary:
Functions: Protects body; helps regulate body temperature; detects sensations such as touch, pain,
warmth, and cold
Components: Skin and associated structures (e.g. hair, fingernails and toenails, sweat glands, and oil
glands)
Skeletal:
Functions: Supports and protects body; provides surface area for muscle attachments; aids body
movements
Components: Bones and joints of the body and their associated cartilages
Muscular:
Functions: Participates in body movements, such as walking; maintains posture; produces heat
Components: Skeletal muscle tissue - muscle usually attached to bones (other muscles tissues
include smooth and cardiac)
Nervous:
Functions: Generates action potentials (nerve impulses) to regulate body activities; detects changes
in body’s internal and external environments, interprets changes, and responds by causing muscular
contractions or glandular secretions
Components: Brain, spinal cord, nerves, and special sense organs (e.g. eyes and ears)
Endocrine:
Functions: Regulates body activities by releasing hormones (chemical messengers transported in
blood from endocrine gland or tissue to target organ)
Components: Hormone producing glands (e.g. hypothalamus, pituitary gland, thymus)
Cardiovascular:
Functions: Heart pumps blood through blood vessels; blood carries oxygen and nutrients to cells and
carbon dioxide and wastes away from cells and helps regulate acid-base balance, temperature, and
water content of body fluids; blood components help defend against disease and repair damaged
blood vessels
Components: Heart, blood, and blood vessels
Lymphatic:
Functions: Returns proteins and fluid to blood; carries lipids from gastrointestinal tract to blood;
contains sites of maturation and proliferation of B cells and T cells that protect against disease-
causing microbes
Components: Lymphatic fluid and vessels; spleen; thymus; lymph nodes; tonsils; cells that carry out
immune responses (e.g. B cells, T cells and others)
Respiratory:
Functions: Transfers oxygen from inhaled air to blood and carbon dioxide from blood to exhaled air;
air flowing out of lungs through vocal cords produces sounds
Components: Lungs, air passageways such as the pharynx (throat), larynx (voice box), trachea
(windpipe) and bronchial tubes leading into and out of the lungs
Digestive:
Functions: Achieves physical and chemical breakdown of food; absorbs nutrients; eliminates solid
wastes
Components: Mouth, pharynx, oesophagus, stomach, small and large intestines, and anus; also
includes accessory organs that assist in digestive processes such as salivary gland, liver, gall bladder
and pancreas.
Urinary/Renal:
Functions: Produces, stores, and eliminates urine; eliminates wastes and regulates volume and
chemical composition of blood; helps regulate production of red blood cells.
Components: Kidneys, ureters, urinary bladder, and urethra
Reproductive:
Functions: Gonads produce gametes (sperm or oocytes) that unite to form a new organism; gonads
also release hormones that regulate reproduction and other body processes
Components: Gonads (testes in males and ovaries in females) and associated organs (e.g. vagina,
mammary glands in females and prostate, penis in males)
Body Cavities:
Major body cavities: Dorsal (back/posterior) and Ventral (front/anterior)
Dorsal cavity is subdivided into:
- Cranial cavity (brain)
- Vertebral/spinal cavity (spine and beginning of spinal nerves)
Ventral cavity is subdivided into:
- Thoracic cavity (organs include lungs, heart, diaphragm)
- Abdominal cavity (e.g. stomach, liver)
- Pelvic cavity (e.g. reproductive organs)
Organic Molecules in the Body:
NOTE: All organic molecules always contain carbon (remember: CHONPS)
Carbohydrates:
Major function: provide energy needed for life
Lipids:
Major types and functions:
- Fatty acids (generate ATP; forms triglycerides
and phospholipids)
- Triglycerides (protection, insulation, energy
storage)
- Phospholipids (cell membrane major
component)
- Steroids (sex hormones, vitamin D, adrenal
hormones)
Proteins:
Nucleic Acids:
Major Function: Stores information used to make proteins
Examples: DNA and RNA
Homeostasis:
Definition: Homeostasis is the condition of equilibrium (balance) in the body’s internal environment
due to the constant interaction of the body’s many regulatory processes.
Importance of Homeostasis:
Homeostasis keeps the internal environment of the body within normal limits in order to prevent
complications such as disease and cancer.
NOTE:
- Homeostasis is a dynamic condition. In response to changing conditions, the body’s
equilibrium can shift among points in a narrow range that is compatible with maintaining
life.
- Internal environment – extracellular fluid (the fluid that surrounds all body’s cells)
- Proper functioning of cells depends on precise regulation of the composition of the
environment surrounding them e.g. temperature, glucose concentration
Homeostasis is mediated by:
- Nervous system (nerves): rapid response, detects changes and sends nerve impulses to
counteract changes
- Endocrine system (hormones): slower response, secretion of hormones into blood
Key components of Feedback Loop/Feedback System:
1. Stimulus (a change in a controlled condition)
2. Receptor: monitors changes from set point/controlled condition
3. Control centre: determines the initial set point range, analyses information from receptors
and determines response (brain or spinal cord)
4. Effector: produces response (with aim to maintain homeostasis)
5. Response: alters the controlled condition
2 Feedback Pathways:
Negative feedback:
- Reverses a change in a controlled condition
- E.g. Temperature regulation, blood glucose regulation, blood pressure regulation
Positive feedback:
- Strengthens a change in a controlled condition
- E.g. Childbirth, blood clotting
Together these feedback pathways help to maintain homeostasis throughout the body’s systems.
Week 2: Cell Structure and Function
Textbook readings: 55-57 (ATP), 63-66, 3.6 (protein synthesis up to transcription page 90), 102
Learning Objectives:
1. List the major organelles within cells and briefly describe their function. (Refer to Learning
Activity Worksheet)
2. Describe the basic structure and function of the plasma membrane.
3. Describe how cells are specialised according to function.
4. Describe simply the main events of protein synthesis.
5. Describe the ATP-ADP cycle.
6. Describe briefly the process of cellular respiration. Distinguish between aerobic and
anaerobic respiration.
NOTE: The cytoplasm is made up of the cytosol, organelles and the nucleus.
Plasma Membrane:
Structure:
The plasma membrane is a flexible yet sturdy barrier that surrounds and contains the cytoplasm of
the cell.
The basic structural framework of the plasma membrane is the lipid bilayer, two back-to-back layers
made up of 3 types of lipid molecules – phospholipids, cholesterol and glycolipids (lipids with
attached carbohydrate groups: NOTE ‘glyco’ = carbohydrate).
NOTE: The bilayer arrangement occurs because the lipids are amphipathic molecules, which means
they have both polar (phosphate head) and non-polar (fatty acid tail: which are hydrocarbon chains)
parts.