Unit 3: How do organisms sustain themselves? Flashcards
What are macronutrients
Carbohydrates ( Monosaccharides)
Proteins ( Amino Acids)
Fats/ Lipids ( Fatty Acids & Glycerol)
What are micronutrients
Vitamins
Minerals
Fibre
Water
4 stages of the digestive system
Ingestion
Digestion
Absorption
Assimilation
Elimination
What are the two types of digestion
Chemical Digestion ( Stomach Acidic, gastric juices)
Mechanical Digestion - Peristalsis ( Wave like movements in esophagus moves food down)
and Churning in Stomach
What is the function of villi and micro villi in the small intestine?
Micro villi are made up of many folds that increase the surface area therefore increasing the absorption of nutrients.
They are vascular and take nutrients to the blood stream.
What organs are involved in the digestion system
Mouth,
Esophagus,
Stomach,
Small Intestine,
Large Intestine,
Rectum,
Anus,
Salivary glands
Liver
Pancreas
Gallbladder
What is the role of saliva in digestion
Before ingestion,
-> the salivary glands produce saliva when stimulated by appetizing food.
The saliva has enzymes that will help in breaking down the food.
How do you test for starch
Iodine test - product turns blue-black = Positive
How do you test for Protein
Biuret solution - product turns purple - lilac = Positive
How do you test for Sugars
Benedict’s test & hot water bath ( turns green -> yellow -> brick -> red = positive)
How do you test for Lipids
Ethanol test - product has cloudy emulsion = positive
What is the function of the respiratory system?
The respiratory system allows a mammal to breath. Take in oxygen, give it to red blood cells
which is essential for the body to function
it is the process of exchanging oxygen and carbon dioxide.
How does oxygen reach the alveoli?
When oxygen is inhaled it travels down the trachea into the bronchi, then further into a bronchiole. Where it reaches the alveoli which are air sacs and the site of gas exchange
What is the structure of an alveolus and how it is related to the function
State 3 points
- Alveoli are made up of one layer of thin cells, similar to the blood capillaries next to it creating a short diffusion pathway. Which increases the rate at which carbon dioxide and oxygen can diffuse across
- Alveoli have a very large surface area which increases the rate of diffusion ( Surface area to volume ratio)
- Alveoli are moist that allows gases to dissolve and increases the rate of diffusion.
Structure of the heart
Right Atrium Left Atrium
Right Ventricle Left Ventricle
Which side of the heart is more muscular
left side
Which vein carries deoxygenated blood to the heart?
Vena Cava
What do arteries do?
Carry oxygenated blood away from the heart
What do veins do?
Carry deoxygenated blood to the heart
What is homeostasis
Homeostasis is a state of balance that an organism must stay in
What are factors that must be controlled in homeostasis?
pH level
Blood glucose ( hypoglycemia-hyperglycemia)
Internal Body Temperature
How are hormones different from enzymes
Hormones are directly secreted into the blood. And they are responsible for maintaining balance in the body.
What happens during hypothermia
Vasoconstriction ( blood vessels get smaller)
Shivering/ Muscles Contract
Piloerection ( goosebumps)
What happens during hyperthermia
Vasodilation ( blood vessels get bigger)
Sweating
Less urine
Structure of the artery and its relation to function
Arteries are strong and elastic. Arteries are constantly pumping and face a lot of pressure.
Structure of the vein and its relation to function
They are large and has valves to prevent backflow.
Carries alot of blood to the heart.
Structure of capillaries and its relation to function
Small and have thin permeable walls. They need to transfer nutrients through diffusion.
What is a positive feedback loop ( Homeostasis)
When some variable triggers an intensifying response.
While delivering a baby -
Pushing baby pressure -> hormones released -> contractions -> more pushing baby pressure ( CYCLE)
What is a negative feedback loop ( Homeostasis)
When some variable triggers a counteracting response - in order to come back to some set point
Sweating - the heat triggers your body to feel hot, triggers a sweating response in order for your body temperature to come back to normal.
What is an example of when the negative feedback loop is not working ( Diabetes)
The pancreas is not producing insulin which allows glucose to be taken into cells which makes ATP and energy.
Patient has to be administered insulin externally.
What does the Pulmonary artery do?
Carries deoxygenated blood from the heart to the lungs for gas exchange
What does the pulmonary vein do
Carries oxygenated blood from the lung to the heart.
What is active transport?
Active transport moves molecules from lower to higher concentration ( i.e against their concentration gradient) - requires energy from respiration
What is osmosis
State one example
Osmosis is a process where solvent molecules move through a semipermeable membrane from a higher concentration region to a lower concentration region.
Example: Water is absorbed from the soil through osmosis. The plant roots have a higher concentration than the soil, so water flows into the roots.
Hypotonic
Hypertonic
Isotonic
Hypotonic - low solute level, water moves into the cell causing it to swell ( turgid )
Hypertonic - high solute level, water moves out of the cell causing it to shrink ( plasmolyzed)
Isotonic - equal solute concentration
no change in cell shape
CHNOPS ( acronym for biogeochemical cycles)
Carbon
Hydrogen
Nitrogen
Oxygen
Phosphorous
Sulfur
