topic 2 - organisation

Question 1

what is a tissue? (bio)

Answer 1

a tissue is a group of similar cells that work together to carry out a particular function

Question 2

what is a organ?

Answer 2

an organ is a group of different tissues that work together to perform a certain funtion

Question 3

what is an organ system?

Answer 3

an organ system is a group of organs working to perform a particulate function

heart and lungs pumping oxygenated blood

Question 4

what do glands do?

Answer 4

glands makes and puts out hormones that do a specific job in your body

Question 5

the digestive system

Answer 5

the stomach - where food is digested
the liver - produces bile
the small intestine - where food is digested and soluble food molecules are absorbed
the large intestine - where water is absorbed

Question 6

lungs.

Answer 6

the lungs are in the thorax, that’s the top part of the body. the diaphragm separates the thorax and the abdomen. the lungs are protected by the rib cage.

the air u breathe goes into the trachea then splits into two tubes called bronchi, which splits into smaller tubes called bronchioles which go into alveoli

Question 7

what is alveoli

Answer 7

alveoli is where gas exchange happens. there are millions of these tiny sacs in the lungs

Question 8

the circulatory system

Answer 8

heart to lungs
lungs to heart
heart to body
body to heart

Question 9

blood flow through the heart

Answer 9

vena cava into right atrium 
right atrium into pulmonary artery 
pulmonary artery into lungs
lungs into pulmonary vein
pulmonary vein into left atrium 
left atrium into left ventricle
left ventricle into aorta

Question 10

arteries

Answer 10

blood vessels which carry blood away from heart. Carries blood at high pressure. artery walls are strong and elastic. has a small lumen

Question 11

capillaries

Answer 11

arteries branch into capillaries. they are one cell thick to allow diffusion to happen more easily.

Question 12

veins

Answer 12

capillaries join up to form veins. they carry blood to the heart. low pressure. has a large lumen. also has valves which stop back flow

Question 13

structure of leaf structure

Answer 13

epidermal tissue - covers the whole plant
palisade mesophyll tissue - where most photosynthesis happens
spongy mesophyll tissue - has spaces which allow gases to diffuse in and out of the cells
meristem tissue - found at tips of shoots and roots, is able to differentiate changes in environment

Question 14

phloem

Answer 14

made of elongated living cells with small pores in end walls to allow cell sap to flow through. transport goes in both directions - this is called translocation

Question 15

xylem

Answer 15

made of dead cells joined end to end. strengthened by lignin. carries water and moves in one direction - roots to leaves. this is called the transpiration stream

Question 16

what can transpiration be effected by?

Answer 16

light intensity
temp
air flow
humidity

Question 17

guard cells

Answer 17

they surround stoma. kidney shape. when the plant has water, they go plump and turgid which opens them up for gas exchange.

when the plant doesn’t have enough water the cells go flaccid which allow them to close in order to stop water vapour escaping.

Question 18

health

Answer 18

health is the state of physical and mental well being

Question 19

communicable disease

Answer 19

diseases which spread from person to person. they can be caused by bacteria, viruses, parasites and fungi.

Question 20

non- communicable disease

Answer 20

diseases which cannot spread between people and animals. cancer is an example

Question 21

cardiovascular disease

Answer 21

used to describe diseases to the heart. a common one is coronary heart disease.

Question 22

statins

Answer 22

drugs which reduce cholesterol present in bloodstream, LDL cholesterol - low density. however it’s a long term drug and someone can easily forget to take it and there are side effects such as headaches, kidney failure, liver damage, and memory loss.

Question 23

artificial hearts

Answer 23

used if there are no donors available. not usually a permanent fix.

Question 24

enzymes

Answer 24

a biological catalyst - increases the speed of a reaction, without being changed or used up in the reaction

Question 25

active site

Answer 25

all enzymes have an active site with a unique shape. lock and key. enzyme and substrate.

Question 26

carbohydrases

Answer 26

carbohydrases convert carbohydrates into simple sugars

Question 27

protease

Answer 27

catalyse the conversion of protein into amino acids

Question 28

lipases

Answer 28

catalyse the conversion of lipids into glycerol

Question 29

testing for sugars

Answer 29

prepare food sample in a test tube

prepare a water bath at 75c

add Benedict’s solution to the test tube

place the tube in the water bath for 5 mins

the colour will change from blue to green, yellow or red - depends on how much sugar there is

Question 30

testing for starch

Answer 30

prepare food sample

add iodine solution

if starch is present the solution will change from orange to blue/black

Question 31

testing for proteins

Answer 31

prepare food sample

add biuret solution

gently shake

colour will change from blue to purple of protein is present

Question 32

testing for lipids

Answer 32

prepare food sample

add Sudan III stain solution

shake well

the solution stains lipids so if any are present the top layer will be red