1. Animal tissues, organs & organ systems Flashcards
What are Specialised cells?
Specialised cells:
. cells that DEVELOP and become more EFFICIENT at their job eg:
. SPERM cell - long tail to propel the sperm to FERTILISE the EGG
. MUSCLE cells - can CONTRACT to bring about MOVEMENT
. NERVE CELL - long with branches to carry NERVE IMPULSES
. PLANT ROOT HAIR CELL - long root to INCREASE THE SURFACE AREA to ABOSRB WATER & MINERALS
. XYLEM cells in PLANT - CELL WALL is STRENGTHENED & XYLEM CELLS are end to end to TRANSPORT WATER
What is a TISSUE?
A tissue is:
A GROUP of CELLS with a SIMILAR STRUCTURE & FUNCTION
eg Muscle tissue CONTRACT TO PRODUCE MOVEMENT
What is a cell?
Cells are the BASIC BUILDING BLOCKS OF all LIVING ORGANISMS
Cells can develop and become SPECIALISED Cells - good at doing one thing eg sperm cells, nerve cells, muscle cells
What is an ORGAN SYSTEM?
ORGAN SYSTEM
An Organ system are a group of ORGANS that work TOGETHER to perform a particular jobs eg DIGESTIVE SYSTEM to DIGEST & ABSORB FOOD
What are ENZYMES?
ENZYMES are:
. Catalysts - they SPEED UP chemical reactions
. They are all LARGE PROTEINS
. They work best at a specific TEMPERATURE & PH - called the OPTIMUM
What theory is used to describe how enzymes work?
LOCK & KEY THEORY is used to explain how enzymes work
What can make enzymes change shape?
HIGH TEMPERATURES & EXTREMES PH can make enzymes change shape.
What is the process called when enzymes change shape?
DENATURING is when enzymes change shape.
The enzyme no longer works because the LOCK & KEY no longer fits together
What do digestive enzymes do?
The digestive enzymes - PROTEASE LIPASE & CARBOHYDRASE digest PROTEINS - LIPIDS & CARBOHYDRATES to produce SMALLER MOLECULES.
The benefit is that these smaller molecules can be EASILY ABSORBED INTO THE BLOODSTREAM.
What can denature (make it stop working & shape shape) an enzyme?
H E A T can denature an enzyme and make it change shape and stop working
How many systems does the human circulation system have?
The human circulation systems is a DOUBLE system
How many times does the blood passes through the heart on each circuit?
The blood passes through the heart TWICE on each circuit.
Where is BILE produced?
Bile is produced in the LIVER
Where is bile STORED?
Bile is stored in the GALL BLADDER
What is the test for sugar/glucose?
Test for glucose?
. Add BENEDICT’S Re-Agent
. Heat in a water bath x 2 mins
. If SUGAR present - it will turn RED
. Don’t heat for too LONG
What is the test for STARCH?
Test for Starch?
. Add IODINE SOLUTION
. If starch present - it will turn BLUE/BLACK
What is the test for protein?
Test for Protein?
. Add biuret re-agent
. If protein present it will turn PURPLE
. Purple might be difficult to see - solve problem - hold tube in front of a WHITE SHEET of Paper
Where is AMYLASE produced?
AMYLASE is A DIGESTIVE ENZYME & is produced in:
. SALIVARY GLANDS & the PANCREAS
. It is a CARBOHYDRATE that breaks down STARCH into SUGAR
What is PROTEASE?
Protease is a DIGESTIVE ENZYME. It:
. is produced in the STOMACH, PANCREAS & SMALL INTESTINE
. It breaks down PROTEINS into AMINO ACIDS
What is LIPASE?
LIPASE is a DIGESTIVE ENZYME. It:
. is produced in the PANCREAS & SMALL INTESTINE
. breaks down LIPIDS (FATS) into fatty ACIDS & GLYCEROL
What does BILE do?
Bile is:
. a liquid made in the LIVER
. STORED in the GALL BLADDER
. It is ALKALINE to neutralise HYDROCHLORIC ACID from the STOMACH
. Bile BREAKS up FAT droplets into SMALLER ones
REQUIRED PRACTICAL - the effects of pH on the reaction of AMYLASE ENZYME
pH in the rate of reaction of AMYLASE ENZYME
- TWO test tubes - one with amylase & another test tube with starch solution into a water bath at 37 degrees
- After 5 mins add the amylase solution to the STARCH
- Every 30 SECONDS take a drop from the mixture & test for STARCH using IODINE SOLUTION
- Records how long it take for the STARCH to be completely DIGESTED
- Possible errors - after mixing the TUBE must be kept in the water bath
- The DEPENDENT VARIABLE is TIME - ie the time taken for STARCH to be digested
- Care if a bunsen burner is used. Do not spill IODINE SOLUTION on the skin
- CONTROL VARIABLES - kept the same eg temperature, volume of amlase
What type of molecule is an ENZYME?
An enzyme is a PROTEIN molecule
What type of enzyme is use to predigest proteins?
PROTEASE enzyme is used to pre-digest proteins.
