Animals, Tissues Organs And Organ Systems Flashcards
What are specialised cells
Specialised cells carry out a particular function
What is differentiation
Differentiation is the process by which cells become specialised for a particular job amd it occurs during the development of a multicelluar organism
What do specialised cells do
Specialised cells form tissue which form organs which form organ systems
What is a tissue
A group of similar cells that work togteher to csrry out a particular function
Examples of tissues
- Muscuscular tissue, which contracts to move whatever its attatched to
- glandualar tissue, whcih makes and secretes chemicals like enzymes and horomones
- epithelial tissue which covers some parts of the body
What is an organ
A group of tissues working together to perform a certain function
What is an organ system
A group of organs workimg togteher to perform a specific function and organ systems work together to make entire organisms
What are enzymes
Living things provide enzymes to act as biological catalysts. Enzymes reduce the need for high temperatures and we only have enzymes for useful reactions in the body
What is a cataylst
It is a substance ehich increaes the speed of a reaction without being changed or used up in the reaction
What are the enzymes made up of
Enzymes are all large proteins and all proteins are made up of chains of ammino acid
What is an active site
Every enzyme has an active site with a unique shale that fits onto the substance involved in a reaction
Why do enzymes catalyse one reaction
Enzymes usually only catalyse one specific reaction because it needs to fit into its active site
How does temperature affect enzymes
The higher the temperature the rate increases at first but if it gets too hot some of the bonds holding the enzyme together break. Changing the shape of the active site do the substrate won’t fit anymore. The enzyme is said to be denatured
How does PH affect enzymes
If the PH is too high or low it interferes with the bonds and denatured it.
All enzymes have an optimum PH and it is often neutral 7 but not always
How to detect if starch is presnt
The enzyme amylase catalyses the breakdown of starch to maltose. Its easy to detect starch using iodine solution . If starch is present tbe iodine solution will turn from browny-orange to blue-black
Where are the enzymes produced
The enzymes used in digestion are produced by cells and then realesed into the gut and mixed with food
How are starch, protein and fat digested
Starch protein and fats are too big to pass through the walls of the digestive system so digestive enzymes break them into smaller Ones like sugars, amimo acids, glycerol and fstty acids. These csn go through the walls and into the bloodstream
What is amylase
Amylase is an example of a caybohydrase it breajs down starch into simple sugars
Where is amylase produced
Salivarly glands, the pancreas, the small intestine
Where is protease produced
The stomach, the pancreas, small inteisne
What does lipase do
Lipase converts lipids into glycerol and fatty acids and are made in the pancreas and smalk intetsije
How deos the body use the products of digestion
The body makes good use of the products. They are used to make new carbohydates, proteins and lipids, some of the glucose that is made is used in respirstion
What is bile
Bile is produced in the liver, stored in the gall bladder beforre it id realesed into the small intestine
What does bile do
The hydrochloric acid in the stomach makes the PH too acidic for enzymes in the small integsine to work proeperly. Bile is alkaline- it neutralises the acid and makes conditions alkaline.
Bile enulsifies fat ( breaks fat into tiny droplets) to increse surface area and makes digestion faster
Where are enzymes produced
Enzymes used in the digestive systen are produced by specialised cells in glands in gut lining
What are different enzymes for
Different enzymes cataylse the breakdown for diggerent food molecules
Where is amylase produced
Salivarly glands
What does the pancreas do
Pancreas produces protease, amylase and lipase enzymes and realeses them into the small intetsine
What does the small intetsine do
The small intestine is where the digested food is absorbed
Out of the digestive system into the blood
How to prepare a food sample
- break up a piece of food with a mortar and pestle
- transfer the ground up food to a beaker and some distilled water
- give the mixture a good stir with a glass rod to dissolve some of the food
- filter the solution using a funnel lined with filter paper to get rid of solid bits of food
What is the test for sugars
The benedicts solution is used to test for sugars
How to do the benedcits test
- transfer 5cm^3 of the food sample into a test tube
- prepare a water bath so thats its set to 75°c
- add about 10 drops of benedicts soltion usinf a pippete
- place the tube in the bath using a test tube holder for 5 mins making sure the tube is poitning awah from you
- if the food contains a reducing sugar the solution will turn from the normal blue coloir to uellow, green or brick red, depemding on how much sugar it has
What is the test for starch
You can use iodine to test for starch
How to do the iodine test
Transfer 5cm^3 of your food sample into a test tube
- add a few drops of iodine solution snd gently shake. If the sample contains starch, the colour of the solution will change from browny orange to black or blue black
What is the test for protein
Bieuret test
How to do the biuret test
Transfer 2cm^3 of your sample into a tube
Add 2cm^3 of biuret solution to the sample and shake
If the sample contains protein it will chnsge frok blue to pink or purple
Where are the lungs
The lungs are in the thorax which is the top part of your body
What are the lungs
The lungs are like big pink sponges and are protected by the ribcage. Theyre suroundded by the pleural membranes
How do lungs work
The air that you breathe in goes through the trachea. This splits into two tubes called bronchi, one going to each lung
The bronchi split split into progressivly smaller tubes called bronchioles. The bronchioles finally end at skall bags called alveoli where gas exchange happens
Where does gas exchange happen
The lungs contain millions of little air sacs called aleveoli surrounded by a network of blood capillaries.
How does gas exchange work
The blood passing next to the alveoli has just returned to the lungs from the rest of the body, so it contains a lot of carbon dioxide and very little oxygen. Oxygen diffuses out of the albeolus (high concentration) into the blood (low concentration). Carbon dioxide diffuses out of the blood (high concentration) into the alveolus (low concentration) to be breathed out
When the blood reaches body cells oxygen is released from the red blood cells (high concentration) and difusses into the body cells (lowconcentration)
At the same time carbon dioxide difuses out of the body cells(high concentration) into the blood ( low concentration). Its then carried back to the lungs
What does the circulatory system do
The circulatory system carries food and oxygen to every cell in the body. It also does a waste collection service- it carries waste products to where they can be removed form the body
What is the circulatory system
It is made up of the heart, blood vessels and blood, humans have a double circulatory system- two circuits joined together
What happens in the first circuit of the circulatory system
The right ventricle pumps deoxygenated blood to the lungs to take in oxygen. The blood then returns to the heart
What happens in the second circuit of the circulatory system
The left ventricle pumps oxygenated blood around all the other organs of the body. The blood gives up its oxygen at the body cells and the deoxygenated blood returns to the heart to be pumped out to the lungs again
What is the heart
The heart is the pumping organ that keeps the blood flowing around the body. The walls of the heart are mostly made of muscle tissue
Why does the heart have valves
The heart has valves to ensure thay blood flows in the right direction
How does the heart pump blood around the body
Blood flows into the two atria from the vena cava and the pulmonary vein. The atria contract, pushing the blood into the ventricles. The ventricles contract, forcing the blood into the pulmonary artery and the aorta and out of the heart. The blood then flows to the organs through arteries and returns through veins. The atria fill again and the cycle restarts
How does the heart get the oxygenated blood it neede
Arteries called cononary arteries branch off the aorta and surround the heart making sure that the heart gets all the oxygenated blood it needs
How is your resting heartrate controlled
Your resting heartrate is controlled by a group of cels in the right atrium wall that act as a pacemaker
How does the natural pacemaker work
The cells in the right atrium wall produce a small electric impulse which spreads to the surrounding muscle cells, causijf them to contract
