Unit 1: AOS 2, DP 2 Flashcards
Multicellular organisms have
specialised cells used to perform different functions that serve the needs of the whole organism
The simplest level of organization
Cellular level (sponges)
Tissues are formed by
group of cells that act in a coordinated manner
Two-layer body plan
tissue level organisation (jellyfish, corals, hydra)
Major tissue types
epithelial, muscle, connective, nervous
Organs are a
group of different kinds of tissues to form a discrete structure that works cooperatively to perform a specific function
3-layer body plan
First organ level organisation (flatworms)
Systems are
a group of organs that cooperate to carry out single life-sustaining functions (excretion, digestion)
Systems do not
act in isolation and are dependent on each other
Digestive system
Breaks down macromolecules to be absorbed and used for energy production, growth, maintenance & repair
Digestive tissues
muscosa (epithelial), sub-mucosa (connective), muscularis (muscle), serosa (connective)
Mouth (digestive)
teeth mech breakdown, enzymes in saliva chem breakdown
Oesophagus (digestive)
transports food to the stomach via peristalsis
Stomach (digestive)
temporary holding chamber, three layers of muscles churn contents, acidic conditions and active enzymes digest fats & start digestion of proteins
Liver (digestive)
produces bile which aids digestion
Pancreas (digestive)
produces enzymes
Small intestine (digestive)
final stage of digestion and absorption of nutrients; mucosa distinguished by villi, crypts, microvilli
Large Intestine (digestive)
includes caecum, colon, rectum, anus, includes reabsorption of water, formation/storage faeces, elimination of faeces & maintenance gut bacteria
Endocrine System
Network of endocrine glands that deliver chemical messages through hormones in the blood stream to target tissues
Pituitary gland (endocrine)
base of brain below the hypothalamus
Anterior pituitary (endocrine)
made of glandular tissue that synthesizes and secretes hormones that activate other endocrine glands
Posterior pituitary (endocrine)
made of neural tissue that stores and releases hormones sent from the hypothalamus
Adrenal gland (endocrine)
small endocrine located on top of kidneys
Corticoid hormones (endocrine)
steroid hormones, produced by cells of cortex of adrenal glands
Cortisol (endocrine)
steroid hormone produced by adrenal cortex, controls blood glucose levels during stress and body’s recovery from stress response
Adrenaline (endocrine)
fight or flight hormone
Thyroid gland (endocrine)
produces/secretes hormones including T3/T4
Parathyroid gland (endocrine)
networks of capillary vessels throughout their tissue
Excretory System
process of removal from the body of various types of waste material arising from its metabolic activities
Urinary tract
hollow organs (ureters, bladder, urethra) transport urine to the outside of the body
Tissues (excretory)
- Epithelial tissue: linings formed by transitional epithelium
- Connective tissue
- Muscle tissue
Kidney (excretory)
filtration, reabsorption, secretion, excretion
o Remove metabolic wastes from blood, conserve salts and water maintained within narrow limits (osmoregulatory function)
Ureter (excretory)
transport urine made in kidney to the bladder
Urinary bladder (excretory)
temporary storage for urine
Urethra (excretory)
tube that allows urine to pass outside the body
