Flashcards in B1 Deck (25):
Complex and include all animal and plant cells.
Smaller and simpler cells.
Contains genetic material that controls the activities of the cell.
Gel-like substance where most of the chemical reactions happen. It contains enzymes that control these chemical reaction.
Holds the cell together and controls what goes in and out.
These are where most of the reactions for aerobic respiration to take place. Respiration transfers energy that the cell needs to work.
These are where proteins are made in the cell.
Rigid cell wall...
Made of cellulose. It supports the cell and strengthens it.
Contains cell sap, a weak solution of sugar and salts.
Where photosynthesis occurs, which makes food for the plant. They contain a green substance called chlorophyll, which absorbs the light needed for photosynthesis.
Bacterial cell, prokaryotic or eukaryotic?
Magnification= image size/ real size
How to prepare a slide to view an onion cell. PRACTICAL.
1. Add a drop of water to the middle of a clean side.
2.Cut up an onion and separate it out into layers. Use tweezers to peel off some epidermal tissue from the bottom of one of the layers.
3. Use tweezers and place epidermal tissue into the water on the slide.
4. Add a drop of iodine solution. Iodine solution is a stain. Stains are used to highlight objects in a cell by adding colour to them.
5. Place a cover slip on top. To do this, stand the cover slip upright on the slide, next to the water droplet. Then carefully tilt and lower it so it covers the specimen. Try not to get any air bubbles under there. They’ll obstruct your view of the specimen.
Cells differentiate to become specialised...
1. Differentiation is the process by which a cell changes to become specialised for its job.
2. As cells change, they develop different subcellular structures and turn into different types of cells.
3. Most differentiation occurs as an organism develops. In most animal cells, the ability to differentiate is then lost at an early stage, after they become specialised. However, lots of plant cells dont ever lose this ability.
4. The cells that differentiate in mature animals are mainly used for repairing and replacing cells, such as skin or blood cells.
5. Some cells are undifferentiated cells- they’re called stem cells.
Specialised sperm cell...
Function to get the male DNA to the female DNA. It has a long tail and a streamlined head to help it swim to the egg. There are a lot of mitochondria in the cell to provide the energy needed. It also carries enzymes in its head to digest through the egg cell membrane.
Specialised nerve cell...
Specialised for rapid signalling. The function of nerve cells is to carry electrical signals from one part of the body to another. These cells are long and have branched connections at their ends to connect to other nerve cells and from a network throughout the body.
Specialised muscle cells...
Specialised for contraction. The function is to contract quickly. These cells are long and contain lots of mitochondria to generate the energy needed for contraction .
Specialised root hair cells...
Specialised for absorbing water and minerals. Root hair cells are cells on the surface of plant roots, which grow into long “hairs” that stick out into the soil. This gives the plant a big surface area for absorbing water and mineral ions from soil.
Phloem and xylem cells...
Specialised for transporting substances. Phloem and xylem form tubes, which transport substances such as food and water around plants. To form the tubes, the cells are long and joined end to end. Xylem cells are hollow in the centre and phloem cells have very few subcellular structures, so that stuff can flow through them.
A thread-like structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.
Embryonic stem cells can turn into any type of cell. Can cure many diseases. Can produce identical plants.
Its the gradual movement of particles from places wheres there are lots of them to places where there are fewer of them. DIFFUSION IS THE SPREADING OUT OF PARTICLES FROM AN AREA OF HIGHER CONCENTRATION TO AN AREA OR LOWER CONCENTRATION.
Osmosis is the movement of water molecules across a partially permeable membrane from a region of higher water concentration to a region of lower water concentration.
The movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy.