Digestive system Flashcards
(20 cards)
What is a villus and what is its function ?
A villi are folds located in the inner walls of the small intenstine, they increase the surface area across which food will move and be picked up by blood capillaries.
How is the small intenstine adapted to its function ?
The small intenstines function is absorption, it is adapted to it due to the large surface area increased by villi which are one cell thick and which are formed from micro-villi making more surface area in which absorption can occur through blood capillaries that are one cell thick .
What does the lymp fluid do ?
The lymph fluid in each villi will carry only fats from the small intestine around the body.
What is the small intestines functions ?
chemical digestion and absorption
What is the large intestine responsible for ?
Also known as colon, it is responsible for converting liquid food waste into solid faeces which is egeste throught the anus.
How is the large intestine adapted to its function ?
Water is removed through the walls and into the blood and tissue sourranding the small intestine.
What is the caecum ?
the swollen area above the appendix ( waste may lodge there and affect the appendix causing it to be surgically removed)
What is the appendix ?
the end of the caecum is called the appendix, it is a vestigal organ meaning it no longer has a function
What does the appendix do ?
connecting point for small and large intestine
What is the pancreas ?
both an endocrine ( secretes hormones) and exocrine( secreted product through duct) gland
Function of the pancreas ?
secretes pancreatic juice which is made up of sodium hydrogen carbonate ( neutralises chyme )
produces enzyme amylase
produces hormone insulin ( allows muscle and liver cells to absorb glucose from blood )
What is symbotic bacteria ?
bacteria that is in the colon, they feed on waste and produce B group vitamins and K.
Absorbed in the bloodstream by the colon
What is the function of symbotic bacteria ?
they break down fat, gives us nutrients and digested food.
prevent disease making bacteria from entering our system and developing
fight and control the population of pathogenic bacteria.
Why do we have a symbotic relationship with symbotic bacteria ?
because the bacteria obtains nutrients wile we obtain digested food and vitamins
What is Nutrition?
the way in which a living organism obtains and uses its food
What are the types of Nutrition and give a sentence on each.
Autotrphic - organisms make their own food using photosynthesis
Heterotrophic - organism that gain food from their enviroment. eg. Herbivores, Carnivores and Omnivores.
Give 2 examples of Heterophobes
Parasites - fleas, take in food from dead sources
Saphrophytes - bacteria and fungi, take in food from living sources
Give 2 examples of Heterophobes
Parasites - fleas, take in food from dead sources
Saphrophytes - bacteria and fungi, take in food from living sources
What is digestion ?
also called the alimentary canal, digestion is the physical and chemical breakdown of food into simplier, soluble particles for abrosption and energy utilization.
What are the stages of human nutrition
Ingestion - food is taken in through the mouth
Digestion - Food is broken down - physically = mechanical breakdown ( teeth, chewing)
- chemicaly = brokend down using enzymes
Absoprtion- digested food moves from the alimentary canal and is absorped in the bloodstream
Assimilation- aborsbed nutrients are used for growth and energy
Egestion- removal of unabsorbed waste (faces)
