Cells Biology Yr 7

These are just some cards to help you revise nothng much to them but should help!!!

?
  • Created by: lauren
  • Created on: 23-05-09 12:10

Green Plants Photsynthesis

Animals eat to get food, but green plants make their own food. The process plants use is called photosynthesis. We say that plants can photosynthesise.

These are the things that plants need for photosynthesis:

  • carbon dioxide
  • water
  • light


These are the things that plants make because of photosynthesis:

  • glucose
  • oxygen


We can show photosynthesis as this word equation:

1 of 14

Animal and Plant Cells

carbon dioxide (http://tbn2.google.com/images?q=tbn:XKKCQ18y-ct5GM:http://doozer27.files.wordpress.com/2008/09/plus_sign.jpg)water (+ light energy) (http://z.about.com/d/webclipart/1/0/w/M/1/ap14r.gif)glucose(http://tbn2.google.com/images?q=tbn:XKKCQ18y-ct5GM:http://doozer27.files.wordpress.com/2008/09/plus_sign.jpg) oxygen

(Light energy is shown in brackets because it is not a substance.)

This is the symbol equation for photosynthesis:

(http://www.bbc.co.uk/schools/ks3bitesize/science/images/green_plants_aq.gif)

Where does this process take place in the plant?

2 of 14

Cells and their Functions

Photosynthesis takes place in the chloroplasts in plant cells. Chloroplasts contain a green substance called chlorophyll. This absorbs the light energy needed to make photosynthesis happen. Plants can only photosynthesise in the light.

(http://www.bbc.co.uk/schools/ks3bitesize/science/images/sci_dia_140.gif)

3 of 14

Palisade cells in leaves have lots of chloroplasts


Plants get carbon dioxide from the air through their leaves, and water from the ground through their roots.

Light energy comes from the sun.

The glucose produced can be turned into other substances, such as starch, which is used for storage. The oxygen produced is released into the air from the leaves.

4 of 14

Animal and Plant Cells

(http://getrevising.co.uk/f/t.gif)

Animal cells and plant cells

The basic building block of animals and plants is the cell. Cells are very small and we need a microscope to see them. The photographs show animal cells and plant cells, as seen through a microscope.

(http://faculty.kutztown.edu/friehauf/science_outreach/cheek_cells_005.jpg)

5 of 14

Cells and their Functions

These are cheek cells, seen through a microscope

(http://www.ndpteachers.org/perit/OnionEpidermis.JPG)

These are onion cells, seen through a microscope

Cells are made up of different parts. It is easier to explain what these parts are by using diagrams like the ones below.

6 of 14

(http://www.bbc.co.uk/schools/ks3bitesize/science/images/sci_dia_126.gif)

Animal cells usually have an irregular shape, and plant cells usually have a regular shape

Animal cells and plant cells both contain:

7 of 14

  • cell membrane
  • cytoplasm
  • nucleus


Plant cells only also contain:

  • chloroplasts
  • vacuole
  • cell wall


The table summarises the functions or jobs of these parts.

8 of 14

Part Function Cell membrane Controls what substances can get into and out of the cell. Cytoplasm Jelly-like substance, where chemical reactions happen. In plant cells there's a thin lining, whereas in animal cells most of the cell is cytoplasm. Nucleus Controls what happens inside the cell - it is not a 'brain'. Chloroplast Where photosynthesis happens – chloroplasts contain a green substance called chlorophyll. Vacuole Contains a liquid called cell sap, which keeps the cell firm. Cell wall Made of a tough substance called cellulose, which supports the cell.

9 of 14

Cells and their Functions

Type of animal cell Function Special features Red blood cells
(http://singularityhub.com/wp-content/uploads/2008/08/red-blood-cells.bmp)
To carry oxygen

  • Large surface area, for oxygen to pass through
  • Contains haemoglobin, which joins with oxygen
10 of 14

Nerve cell
(http://www.ngfn.de/englisch/images2/Nervenzelle_is_glossar.jpg) To carry nerve impulses to different parts of the body

  • Long
  • Connections at each end
  • Can carry electrical signals

Female reproductive cell (egg cell)

(http://www.bbc.co.uk/schools/ks3bitesize/science/images/bio_egg.gif) To join with male cell, and then to provide food for the new cell that's been formed

11 of 14

  • Large
  • Contains lots of cytoplasm

Male reproductive cell (sperm cell)

(http://spermomax.net/sperm.jpg) To reach female cell, and join with it

  • Long tail for swimming
  • Head for getting into the female cell

Type of plant cell Function Special features Root hair cell

12 of 14

(http://www.nelsonthornes.com/secondary/science/scinet/scinet/plants/cells/images/hair.gif) To absorb water and minerals

  • Large surface area

Leaf cell

13 of 14

(http://www.dr-sanderson.org/images/palisade%20cell.jpg) To absorb sunlight for photosynthesis

  • Large surface area
  • Lots of chloroplasts
14 of 14

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »