Biology

cells, digestion, Food test RP

animal cell

plant cell

Define nucleus

contains the genetic material (DNA) of the organism controls the cell’s activities

define cytoplasm

the liquid that makes

Define cell membrane

a flexible outer layer that surrounds the cell in which chemical reactions happen. This is mainly water

Define mitochondria

tiny parts of cells floating in the cytoplasm where energy is released rom glucose from food.

Define cell wall

a tough outer layer of the cell, which contains cellulose to provide strength and support to the plant

Define vacuole

A space inside the cytoplasm that contains a watery liquid call cell sap. It keeps the cell firm.

Define chloroplasts

structure found in the cells of green parts of plants only (leaves and stem) which contain a green pigment called chlorophyll in which photosynthesis occurs

Define ribosome

part of a cell where proteins are made

Define plasmid

Only found in bacterial cells. A small loop of DNA

Define genetic material

Long strands of genes not tightly pack in a nucleus

Define Eukaryotic

A complex cell with a nucleus

Define prokaryotic

A smaller cell without a nucleus

Define osmosis

The net movement of water molecules across a partially permeable membrane from a less concentrated solution to a more concentrated solution. It’s a passive process

Define Diffusion

The net movement of a substance from an area of high concentration to an area of low concentration. it’s a passive process

the function of the mouth

mechanical breakdown/chew food

the function of the slivery glands

produce salvia with amylase enzymes to breakdown starch

the function of the oesophagus

(Gullet): push chewed food to stomach. food moved by muscle action

function of the liver

Makes bile Bile: a) provides neutralises stomach acid and b) emulsifies lipids (increases there surface area ) this helps lipids digestion by enzymes

the function of the gall bladder

stores bile

the function of the pancreas

production of digestive enzymes

the function of the small intestine

absorption of small soluble particles

the function of the appendix

useless organ which harbours bacteria (good and bad )

the function of the stomach

Partial digestion of food/ mechanically churns food with HCL and protease enzymes

The function of the large intestine

re-absorption of water

The function of the rectum

Muscular section of the large intestines

The function of the anus

where faeces leaves the body

Define tissue

A group of cells with a similar structure and function

Define organ

A group of tissues preforming specific functions

Define an organ system

A group of organs which work together to form organisms

The apparatus list for the Food tests RP

• Food:potato, carrot, crisps, biscuits, cheese

• Spotting tile

• Pipette

• 10cm3 measuring cylinder or plastic syringe

• Beaker

• Boiling tubes

• tests tubes

• kettle or water bath

• Iodine solution

• Benedict’s reagent

• Biuret reagent

• Ethanol

• Eye protection

What are some safety notes for the Food tests RP ?

• Where eye protection

• If chemicals on skin rinse under cold water

• In case of burns rinse under cold water for 20 minutes

In the food test RP what do we use to test for starch?

We would use Iodine

In the food test RP what would we use to test for glucose ?

We would use Benedict’s solution

In the food tests RP what would we use to test for protein ?

We would use Biuret solution

In the food tests RP what would we use to test for Lipid ?

We would use Ethanol

What are the steps to test for starch ?

1. Put a small piece of the food to test on a spotting tile .

2. Add two drops of the solution you would use onto the food

3. If the solution goes blue-black it contains it

What are the steps to test for glucose ?

1. Mix a small sample of the food with the solution about 3cm³ in a boiling tube

2. Leave it for 2 minutes

3. If the solution goes a brick red it contains it

What are the steps to test for protein ?

1. Mix a small sample of the food with the solution about 3cm³ of the solution

2. leave it for two minutes

3. If the mixture goes play purple it contains it

What are the steps to test for Lipid ?

1. Mix a small sample of the food with about 1cm³ of the solution in a dry test tube

2. Pour the ethanol into a test tube of cold water

3. If the water goes milky white the food contains it