Cell Functions Flashcards
What are cells?
Cells are the basic building units of all living things
What does the cell theory state?
1) All living things are made of cells or cell products
2) A cell is the basic unit of life.
3) A cell is the smallest thing capable of independent reproduction.
What microscopes make the study of cells possible?
Light and electron microscopes
What are eucaryotic cells? Give examples of organisms that contain this cell.
Cells that contain organelles such as a nucleus, mitochondria, etc, e.g. plants, animals, fungi.
What are procaryotic cells? Give examples of organisms that contain this cell.
Cells that have no organelles, e.g. bacteria
What are multicellular organisms?
Organisms that consist of more than one cell.
Name some different types of cells/ cell jobs in the human body.
- Bone cells
- muscle cells
- Blood cells
- Nerve cells
What are tissues?
Cells of the same type working together.
What are organs?
Tissues of the same type working together.
What are organelles?
Organs of a cell/ part of a cell that does a certain job.
What does the nucleus contain and do and who has them?
Contains DNA and controls all the cell functions.
Plants and animals
What does the cell/ plasma membrane do and who has them?
Semi- permeable, controls what enters and leaves the cell.
Plants and animals
What does the mitochondria do and who has them?
Powerhouse of cell, it releases energy from sugar via aerobic respiration. It has its own DNA and is able to reproduce.
Plants and animals.
What do the ribosomes do and who has them?
Makes protein
Plants and animals
What do the chloroplasts do and who has them?
Holds chlorophyl, carries out photosynthesis.
Plants only
What does the vacuole do and who has them?
Stores food/ water
Plants and animals
What does the nucleolus do and who has them?
Produce ribosomes
Plants and animals
What does the Golgi apparatus do and who has them?
Makes secretory products
Plants and animals
What do the centrioles do and who has them?
Forms spindle fibre which pulls chromosomes to opposite ends of the cell during cell division.
Animals only
What does the lysosome do and who has them?
Suicide sacs, they produce powerful enzymes to digest themselves.
Animals only
Who has cell walls?
Plants
What surrounds a cell?
Cell membrane
How do most substances enter cells?
Diffusion (the spreading of something more widely)
How do body cells reproduce?
By mitosis
How does mitosis work?
The DNA is copied exactly and each cell receives a copy of the DNA.
What are the three things mitosis allow organisms to do?
1) Grow- increase the number of cells
2) Repair- damaged tissues, e.g. broken bones
3) Maintenance- replace cells that die, e.g. blood cells, skin cells
What are the four bases that make up DNA and which bases go with which.
Adenine Guanine Cytosine Thymine A-T C-G
Who discovered the structure of DNA?
Watson and Crick
What shape is DNA?
Double helix form
DNA exists as strands called……?
chromosomes
How many chromosomes do human body cells contain?
46 chromosomes (23 pairs)
What is a gene?
Small part of a chromosome that controls a single inherited feature.
What do genes control?
The protein we make.
How are proteins made?
By linking amino acids together.
What does each group of three bases (e.g. AAT) on the DNA control?
1 amino acid in the protein
What are the set of chromosomes of an organism called?
Karyotype
What is mRNA
Messeenger RNA. It is a copy of a gene message.
What does mRNA control?
The building of a protein in the ribosomes.
What is tRNA?
Transfer RNA
What does tRNA do?
Brings amino acids to the ribosomes to make the protein.
What are mutations?
Permanent changes in the DNA of an organism.
What does mutation change?
A protein an organism makes.
Where must a mutation occur in order to be inherited?
Sperm or egg
What is biotechnology?
Using a living organism to produce a substance useful to humans.
What is recombinant DNA?
When a gene is taken from one species DNA and added to a different species.
What is the altered species called/ said to be?
transgenic
Give an example of biotechnology.
The bacterium E. coli. is used to make the protein insulin to treat human diabetics.
What are transgenic species also called?
GMO’s- Genetically modified organism
Where are GMO’s commonly used?
agriculture
What is cloning?
The process of producing genetically identical organisms.
Give some examples of cloning.
1) Growing plants from cuttings
2) Tissue culture in plants
3) Combined body cells with egg (nucleus removed) to grow clones animals, e.g. Dolly the sheep.
What is genetic engineering?
Any process which alters the genes in an organism.
