Multicellular Organisms Flashcards
Digestive System Pathway
Mouth > oesophagus > stomach > small intestine > large intestine > rectum > anus.
2 Digestion Types?
- Mechanical: the physical breakdown of larger particles to smaller (no chemical change)
- Chemical: forms new products using enzymes, takes place in the mouth, stomach and small intestine.
4 Digestion functions?
- Ingestion: taking in food (eating)
- Digestion: breaking down food
- Absorption/assimilation: utilisation by body cells
- Egestion: removal of undigested material (not waste).
D.S. – the mouth
- Indigestion
- Process of eating called mastication
- Produces salivary amylase
D.S. – the oesophagus
- Trachea closes off when eating
- Circular muscles that push food (peristalsis)
D.S. – the stomach
- Cardiac sphincter and pyloric sphincter
- Proteases
D.S. – small intestine
- Intestinal juice
- Juice has intestinal proteases, lipases and maltase
D.S. – pancreas
- Pancreatic juice
- Juice has pancreatic proteases, lipases and amylase
Circulatory System purpose
Responsible for transporting:
1. Water
2. Solids (food and waste)
3. Heat
4. Hormones
5. Gases
C.S. essential features
- Able to reach every cell in body
- Fast supply of O2
- Pipeline/flow
- Pump that maintains that flow.
C.S. – main veins and arteries
- Aorta
- P. artery
- P. vein
- Superior vena cava
- Inferior vena cava
C.S. – arteries vs. veins
Arteries:
- thick muscular wall
- smaller lumen
- high pressure
- no valves
Veins:
- thin wall
- larger lumen
- lower pressure
- valves
Respiratory System requirements
- Good concentration difference – O2 should be able to move from high to low O2 concentration with simple diffusion
- Moisture – entire system lined with mucus
- High SA : V ratio
- Transport
- Thin & single-celled barriers
Plant tissues
- Dermal – outer layer (herbaceous or woody)
- Meristematic – replacement cells responsible for growth
- Ground cells – photosynthetic cells, storage cells and packing cells
- Vascular tissue – xylem and phloem
P.S. – Vascular tissues
Xylem:
- Transports water
- Thick walls with lignin
- No obstruction
- Dead cells
- One-way movement
Phloem:
- Transports food and nutrients both ways
- Companion cells on the outside
- Thin walls
- Sieve plates that slow down distribution of syrup
P.S. – Companion cells
- Have a mitochondria that produces energy which allows active transport of sugar syrup through
P.S. – Water flow
- Adhesion: Attraction between water and lignin which helps in movement of water up the xylem when root pressure is reduced.
- Cohesion: Attraction between water molecules that keeps a continuous column.
P.S. – 2 types of root systems
Tap root system: main roots growing deep for anchorage
Adventitious root system: spread sideways near the ground surface for absorption of ground water and nutrients
C.S. – White blood cells
Have a nucleus.
White blood cell types:
1. Basophils – inflammation
2. Neutrophils – ingest and destroy
3. Eosinophils – destroy
4. Macrophages – ingest and destroy
5. Lymphocytes – Memory
C.S. chambered hearts in animals
Insects: 1 chambered
Fish: 2 chambered
Amphibian/Reptile: 3 chambered
Bird/mammal: 4 chambered
