Unit 1: Cells, Energy Transformations and Digestive System Flashcards
What is the plasma membrane?
Membrane where materials enter/exit a cell
What is simple diffusion?
Movement of materials from an area of high concentration to low concentration
Name 2 characteristics that Eukaryotic cells have, that Prokaryotic cells don’t.
Eukaryotes.... have a defined Nucleus. have linear chromosomes. Complex Structure Large Size
What’s the difference between hydrophilic & hydrophobic?
Hydrophilic = Water Loving Hydrophobic = Water Fearing
What is Osmosis?
Movement of water across semi-permeable membrane from a solution of lower concentration to higher concentration.
What are the 2 major components of pm?
Proteins & Phospholipids
What is a phospholipid made of?
1 molecule is made of 2 fatty chains joined to a phospahet
What are the 2 main types of proteins?
Integral and Peripheral
Where are integral proteins found?
Either side of pm
What can attach to integral proteins?
Carbohydrate Groups
Where are peripheral proteins found?
Exterior of pm
Which of the 2 main proteins separate from the pm easier?
Peripheral
What is the Fluid Mosaic Model?
Model of pm structure suggesting pm as 2D fluid with proteins embedded.
What are the 4 functions of the pm?
- Active Boundary
- Cell Identity
- Receive External Signals
- Transport
What is Facilitated Diffusion?
Form of diffusion involving carrier and channel proteins.
What is Active Transport?
Movement of substances pm in the opposite direction they travel in regular diffusion. So lower to higher.
What is Endocytosis?
Movement of solid particles/bulk liquids into a cell.
What is Exocytosis?
Transport of bulk material out of a cell.
How do plants/algae transform energy?
Sunlight to Chemical via photosynthesis
How do animals/fungi transform energy?
Organic molecules through food. Chemical energy
What is Cellular Respiration?
Process by which chemical energy of glucose is transformed into ATP.
What are Autotrophs?
Organisms that produce their own energy
What are Heterotrophs?
Organism that absorbs food in the form of organic material obtained from their environment.
What is a Photosynthetic Autotroph?
Organism that obtains energy from sunlight.
What is a Chemosynthetic Autotroph?
Organism that obtains energy from carbon fixation.
What is the WORDED formula of Photosynthesis?
Carbon Dioxide + Water ——-> Glucose + Oxygen + Water
chlorophyll
sunlight
What is the CHEMICAL formula of Photosynthesis?
6CO2 + 12H2O ——-> C6H12O6 + 6O2 + 6H2O
chlorophyll
sunlight
What are 2 stages of Photosynthesis?
Light Dependant Stage & Light Independent Stage
Where is chlorophyll found?
Chloroplasts
Where does Light Dependant Stage occur?
Thylakoid membranes (chloroplasts)
Where does Light Independent Stage occur?
Stroma
Difference between Aerobic Respiration and Anaerobic Respiration?
Aerobic Respiration occurs in the presence of oxygen, Anaerobic Respiration does not.
What is the equation for Alcohol Fermentation?
C6H12O6 ————> 2CH3CH2OH + 2CO2
Glucose ————> Ethanol + Carbon Dioxide
Yeast
What is the formula for Lactic Acid Fermentation?
C6H12O6 ——–> C3H6O3 + ATP
Glucose ——-> lactic acid + ATP
What are 12 components of Digestive System? (Mnemonic)
M Mrs Mouth
S Stephenson Salivary Glands
O Owns Oesophagus
S Some Stomach
L Library Liver
G Goods. Gall Bladder
P Please Pancreas
S Submit Small Intestine
C Cover Caecum
L Letters to Large Intestine
R Request Rectum
A Appeals Anus
How long does digestion take in humans?
Approx 24 hours
How does food move through digestive system?
Via Peristalsis- Muscular contractions
How long is the digestive tract in Humans?
Approx 8 meters
What are the 2 types of digestion?
Mechanical and Chemical
What’s the difference between Mechanical and Chemical Digestion?
Mechanical involves movement like peristalsis or chewing, while chemical involves chemicals such as enzymes to break down food.
What enzyme does Saliva contain?
Amylase
How long is the Oesophagus in Humans?
20-23 cm long
What 4 things make up gastric juice?
Hydrochloric Acid, Water, Mucus & Enzymes
What substance does the Stomach turn the food into?
Chyme
What are the 3 main regions of the Small Intestine?
Duodenum, Jujenum, Ilieum
What 3 organs secrete chemicals which help the Small Intestine to digest food?
Pancreas, Liver & Gall Bladder
What 4 things does the Duodenum break down?
Phospholipids, Carbohydrates, Proteins & Fats
What does the Liver produce?
Bile
When does Bile secrete into the Duodenum?
When it detects chyme in it.
What happens to excess bile in the Duodenum?
It gets stored in Gall Bladder, until needed.
What happens in Jejunum and Ileum?
More enzymes continue to break food down.
What is the Small Intestine lined with?
Villi, which are covered in microvilli
What percentage of absorption occurs in the Small Intestine, and the Stomach/Large Intestine.
90% in Small Intestine, 10% in Stomach/Large Intestine
What 2 things are included in Large Intestine?
Colon and Rectum
How long is the Large Intestine?
Approx 1.5m
What is the Large Intestine’s main function?
To absorb most of the water from the chyme/faeces.
