Cells - organelles and transport Flashcards
Where is DNA found
in the nucleus
Why is DNA important
Stores instructions for protein synthesis
What role do ribosomes play
protein synthesis
what role does endoplasmic retinaculum play
tunnel system involved in fat and protein synthesis
What does the Golgi apparatus do?
modifies and packages proteins for export
What do lysosomes do?
Intracellular digestion
What do peroxisomes do?
Detoxify free radicals
What does the cytoskeleton do
Cellular support and motion
What do centrioles do?
Cell division and form the bases of the cilia and flagella
What are flagella
Long projections made of microtubules that propel the cell
Name the three times of cell junctions
Desmosomes - anchor, tight junctions - seal the membrane; gap junction - communication
When a cell is placed in hypotonic solution, it will
swell because water is moving into the cell
When a cell is placed in hypertonic solution, it will
shrink due to the water moving out of the cells into solution
What is a gene
section of DNA on a chromosome that encodes function. Traits are partially determined by our genes. Each cell has 2 copies of each gene (alleles)
What are proteins?
A large molecule composed of one or more chains of amino acids in a specific order
What role does mRNA play
Carries DNA instructions for protein synthesis to ribosome
What role does transfer RNA (tRNA) play?
Transports amino acids to the ribosome
Transcription is where
DNA info into mRNA
What role does ribosomal RNA (rRNA) play
Forms of the ribosomal structure
Translation is
RNA and ribosome build protein
Why is mRNA very important
3 Base pair codons are read by the ribosome - tRNA has anticodons - codons and anticodons temporarily bind to ensure the correct amino acid is added in the correct positioning in growing protein
What is mitosis?
Division of the nucleus
What is cytokinesis
Division of the cytoplasm
In interphase, there is
DNA replication - G1, S, G2
In mitotic phase, there are 4 stages -
Prophase, metaphase, anaphase and telophase, that result in 2 daughter nuclei
What happens in G1?
Cell is being prepared by duplicating organelles + cytoplasmic components in preparation for division
What happens in S phase
DNA in the nucleus is replicated
What happens in the G2 phase
Cells finishes growing - 2 centrosomes appear in the cytoplasm
Explain the mitotic phase
Prophase = DNA condenses, organises, chromosome structure forms
Metaphase = chromosomes align midway
Anaphase = chromosones separate apart
Telophase = nuclear membranes appear
Cytokinesis = 2 cells are formed
