Year 8 B and P Summer term 1 – Week 3 Name: _________________ Class: _______
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Year 8
B and P
Summer term 1 – Week 3
Name: _________________
Class: _______
1
About this booklet
This booklet contains information that you would be learning if school was open. It’s a mix
of old and new knowledge to support your learning of Science as a whole.
Over the term there will be three mini assessments that must be sent to the Science Team
for marking at [email protected]. You will receive feedback on how to improve
your answers and understanding. The date for submission is listed next to the
assessment.
Work can be submitted either as a Word document or a photo of written work.
You will complete 3 weeks of new learning and two weeks consolidating old learning. The
learning will alternate between new and old each week.
Timetable
Week beginning Pages to complete Mini Assessment deadline Educake deadline
20th April 2020 2-10 24th April 2020 27th April 2020 1st May 2020
4th May 2020 8th May 2020
11th May 2020 15th May 2020 18th May 2020 22nd May 2020
The Vocab
Carbohydrate A molecule in food used as fuel for energy, e.g. sugars and starches. Broken down in digestion by carbohydrase enzymes such as amylase.
Protein A biological molecule used for growth and repair. Broken down by proteases in digestion.
Lipid A biological molecule found in fats and oils, used for energy and making cell membranes. Broken down by lipases in digestion.
Digestion The breakdown of large molecules from food into smaller ones for absorption and use in the body.
Egestion The process of getting rid of undigested or waste material from an organism.
Oesophagus The part of the digestive system connecting the throat and the stomach. Muscular tube.
Pancreas A large organ behind stomach that secretes digestive enzymes to help digestion.
Enzyme A biological catalyst which speeds up chemical reactions in the body. Digestive enzymes break down large molecules into smaller ones in digestion.
Catalyst A substance that speeds up the rate of a chemical reaction without itself being used up or changed.
Starch A carbohydrate that function as a storage molecule in plants; found in cereals and potatoes.
Glucose A simple sugar which is an important energy source in living organisms; made in photosynthesis and used in respiration.
Photosynthesis The process by which green plants use sunlight to make glucose (food) from carbon dioxide and water.
Transpiration The process of water movement through plants – absorbing water from the roots and evaporating from the leaves.
Translocation The movement of materials such as carbohydrates from leaves to other tissues throughout the plant.
Stomata Tiny openings in leaves that can open and close, used in gas exchange (carbon dioxide diffuses in, oxygen diffuses out).
Palisade cell Plant cells located in the upper part of leaves that contain lots of chloroplasts for photosynthesis.
Xylem A tissue in plants that carries water and dissolved minerals from roots up to the rest of the plant.
Phloem A tissue in plants that carries sugars made in photosynthesis and other molecules downwards from the leaves.
2
Lesson 9 – The digestive system (NEW learning)
Last lesson Last week Last term
What are the nutrients in food that give us energy?
What happens if we eat too much sugary and fatty foods?
1. Oil is formed from… A - Dead plants and animals. B - Microscopic plants C - Microscopic animals 2. If 20g of oxygen reacts with hydrogen and forms 50g of water how much hydrogen reacted? A - 70g B - 30g C - 25g Comments:
My
answ
er
Rig
ht
answ
er
Useful links for this lesson
https://www.bbc.co.uk/bitesize/guides/z9pv34j/revision/1
https://www.bbc.co.uk/bitesize/topics/zf339j6/articles/zrm48mn (model digestive system activity)
You could also set your own questions on Educake.
3
The Learning
1. What parts of the body does food pass through?
2. What other organs are important in digestion?
3. What is the name of this organ system?
Watch the demonstration of a model digestive system, then answer the questions. https://www.bbc.co.uk/bitesize/topics/zf339j6/articles/zrm48mn
1. Which part of the model represents the stomach? ___________________________________
2. Where in the digestive system is most water absorbed? ______________________________
3. What is the difference between chemical and mechanical digestion?
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
4. What is egestion? (Hint: see stage 4 below)
________________________________________________________________________________
________________________________________________________________________________
Read the following information and make flashcards of the most important facts:
Stage 1 – The mouth Digestion starts in the mouth where the food is broken down mechanically by the teeth and chemically by the enzyme amylase (contained in saliva). Amylase breaks down carbohydrates into sugars. An enzyme is a biological catalyst that speeds up chemical reactions. Stage 2 – The stomach The food then passes down the oesophagus and into the stomach. When it reaches the stomach, the food mixes with the stomach acid and enzymes. The stomach is a muscular bag which churns the food, breaking it down into small pieces. Stage 3 – The intestines The food passes through into the small intestine. Here more enzymes are released, breaking down carbohydrates, proteins and fats into smaller molecules. The smaller molecules are then absorbed in the small intestine by the finger-like structures called villi. Villi are very good at absorption because they have very thin walls, a large surface area and a strong network of capillaries surrounding them. Stage 4 - The rectum The remaining nutrients move through into the large intestine, where the water is absorbed back into the body. The undigested food molecules that remain form our faeces. The faeces is passed into the rectum and is removed (excreted) from the body through the anus. This is called egestion.
4
The Application
1. Label the diagram with the correct organs, then do look/cover/write/check on the second one.
2. Complete the gaps below using these words:
The salivary glands release ……………………….……. to moisten the food before it goes down the
…………………….. where the ………………………… contract to push the food down towards the
stomach. In the stomach there is hydrochloric …………………….. to break down the food further.
The ………….. intestine absorbs the food into the blood. The large intestine removes ...…..……….
Faeces are then stored in the …………………… and are released through the ………………….....
3. Fill in the gaps: ingestion (eating) → ___________ (breaking down) →
absorption (taking into bloodstream) → __________ (removal from the body)
Anus Saliva Acid Rectum Oesophagus Muscles Water Small
5
Lesson 10 – Absorption in digestion
Do Now:
Last lesson Last week Last term
What are the main parts of the human digestive system?
We need protein in our diet for…
1. What is conservation of mass? A - Mass of reactants = mass of products B - What goes in comes out C - Mass of products is less than reactants 2. What salt does hydrochloric acid form? A - Sulphate B - Chloric C – Chloride Comments:
My
answ
er
Rig
ht
answ
er
Useful links for this lesson
https://www.bbc.co.uk/bitesize/guides/z9pv34j/revision/3
You could also set your own questions on Educake.
6
The Learning
ingestion (eating) → digestion (breaking down) → ABSORPTION → egestion (removal from the body)
Digested food molecules are absorbed in the small intestine. This means that they pass through the wall of the small intestine and into our ___________________.
Once in the bloodstream, the digested food molecules are carried around the body to where they are needed. Only small, ___________ substances (those that can dissolve) can pass across the wall of the small intestine. Large insoluble substances cannot pass through.
How are molecules absorbed? Give the definitions for these processes as well.
1. D……………………….. is when molecules move from
an area of ……………… …………………………. to an area of ……………… …………………………, down a
……………………………. gradient
2. A ……………. T…………………. is when molecules move from
…............................................................................................................................ ..................................
................................................................................................................................................................
The inner wall of the small intestine has adaptations so that substances pass across it quickly and efficiently.
it has a ___________ wall, just ______ cell thick
it has many tiny villi to give a really big ___________ area
it has lots of blood ________________ to carry away the absorbed ___________ molecules
Q: Draw and label two villi from the small intestines with their adaptations that make them good at their job of
absorbing small food molecules.
7
The Application
1. The diagram shows part of the human digestive system.
(a) Write the letter which labels the small intestine. ...............
(b) What process happens in the small intestine? …………………………………………………………………………………………….
(c) Where in the digestive system is most excess water absorbed back into the bloodstream? ………………………………………………………………………….
2. There are several thousand villi in every square centimetre of the lining of the small intestine. The cells in the lining of each villus have folds called microvilli on their outer surfaces.
(a) Explain two ways in which the structure of the villus enables the products of digestion to be absorbed efficiently
1.
2.
3. Villi are found in some parts of the digestive system.
Diagram 1 shows two villi.
(a) Draw a ring around the correct answer to complete each sentence.
muscle.
(i) Structure A is a nerve.
capillary.
dialysis.
(ii) The villi absorb the products of digestion by diffusion.
osmosis.
8
Lesson 11 – Enzymes in digestion (NEW learning)
Do Now:
Last lesson Last week Last term
What nutrient do we absorb via osmosis and where does this happen?
What food contain lots of carbohydrates?
1. Sodium needs to be extracted using… A - Mining B - Reduction with carbon C – Electrolysis 2. What are the products of a reaction between a metal and an acid? A – salt and hydrogen B – salt and water C – carbon dioxide and water Comments:
My
answ
er
Rig
ht
answ
er
Useful links for this lesson
https://www.bbc.co.uk/bitesize/guides/z9pv34j/revision/2
Challenge (if you’re interested!): https://www.bbc.co.uk/bitesize/guides/zcttv9q/revision/5
You could also set your own questions on Educake.
9
The Learning:
What three nutrients must be digested (broken down) before they can be absorbed?
……………………………………., …………………………………….., ……………………………………….
What nutrients are small enough molecules to be absorbed without needing to digest them first?
……………………………………., …………………………………….., ……………………………………….
Enzymes are biological catalysts (they …………………. chemical reactions). They are special proteins that can
break ……………… molecules into ……….…… molecules. There are different enzymes for different nutrients.
carbohydrase enzymes break down starch into ……………………….. An example of this enzyme is …………………..
protease enzymes break down ……………………………… into ………………… acids
lipase enzymes break down …………………………….. (fats and oils) into …………………… acids and ………………….
10
The Application
Watch the video and complete the table - https://www.bbc.co.uk/bitesize/clips/zwksb9q
Large and complex
food molecule
Broken down
into… Enzyme
Where is enzyme
produced?
C Sugars, such as
………………………….
Salivary glands,
Protein Amino …………… P
L
Lipase
(a) Enzymes are used in body cells.
(i) What is an enzyme?
Draw a ring around the correct answer.
an antibody a catalyst a hormone
(ii) All enzymes are made of the same type of substance.
What is this substance?
Draw a ring around the correct answer.
Carbohydrate fat protein
(iii) Where is the enzyme amylase produced in the human body?
Draw a ring around the correct answer.
liver salivary glands stomach
11
The Learning and The Application 2 – Investigating enzyme action
Watch this video and answer the questions below: https://www.youtube.com/watch?v=zsOs3v8Z-P4
To check for the presence of starch, we can use iodine.
This changes colour from ……………………… to …………………………….
when starch is present.
Remember: starch can be broken down into sugars by a carbohydrase enzyme. We can investigate enzyme action
using a carbohydrase to break down starch.
1. What are polymers and monomers? (You can draw them if you’d like.)
______________________________________________________________________________________
______________________________________________________________________________________
______________________________________________________________________________________
2. Why do the solutions need to start at the same temperature?
______________________________________________________________________________________
______________________________________________________________________________________
______________________________________________________________________________________
3. Describe what we observe (see) as time goes on after mixing the starch and amylase together (see
around 5 minutes in the video). Write about the colour changes.
______________________________________________________________________________________
______________________________________________________________________________________
______________________________________________________________________________________
______________________________________________________________________________________
4. When was the digestion of starch by amylase complete?
_____________________________________________________________________________________
5. List some of the control variables used in the experiment (things they kept the same to make the
experiment reliable and fair)
Keeping the solutions at the same ……………………………….
Using the same volume of ………………………………
12
Lesson 12 – Mini Assessment 2- SUBMISSION DEADLINE 8th May 2020
Do Now:
Last lesson Last week Last term
What is a carbohydrase? What does it break down?
Which nutrients do not need to be digested?
1. What gas is released when metal carbonates react with an acid? A – sulphate B – hydrogen C – carbon dioxide 2. What is the formula for hydrochloric acid? A – HCl B – HCh C – HCL
My
answ
er
Rig
ht
answ
er
Related Documents
