Cells Flashcards
What is a cell?
The basic unit of life
Each cell has a defined role
What is an organelle ?
Structure that fulfil important task s
What are some examples of the vital functions of cells ?
Use oxygen vi
A cellular respiration to get energy needed to function
Growth and repair functions of the body
Cel
Selectively per,eagle to ions and organic molecules and controls the movement of substances in and out of cells
What is the basic function of the cytoplasm?
To protect the cell from its surroundings
What is the role of the cytoplasm ?
To make a boundary between th e the inner environment of th excellent Th
Where is the nucleus located ?
The heart of the majority of eukaryotic cells (animal or plant)
What is the nucleus mission ?
To direct and control all activities that occur in the cell
What does the nucleus house?
Dana and the chromosomes which carry the genes. The nucleus directs cell division
What is a eukaryotic cell?
They contain membrane bound organelles, including a nucleus
They can be single felled or multi celles
Ex: humans or plants
What is a prokaryotic cell?
Cells that do not contain a nucleus or any other membrane - bound organelles
What does the cytoplasm comprise of?
Cytosol [gel like substance enclosed within th cell memebrane) and the organelles (the cells internal sub-structures)
What happens in the cytoplasm ?
All of the contents of the cells of prokaryotic organism are contained within the cytoplasm
What are ribosomes responsible for ?
They are responsible for protein synthesis
What are ribosomes
Organelles that are found in the cytoplasm
There can be up to 10 million ribosomes in a cell
They are the cells protein factories
What does the smooth endoplasmes retilicum do?
Synthesizes lipids and metabolizes carbs
What is the rough endoplasmic reticulum?
It is linked to the nucleus’s enveloppe by the ribosomes, it’s membrane is continuous with the outer membrane of the nuclear envelope.
What is the smooth endoplasmic reticulum responsable for?
The synthesis of membranes and certain proteins
What happens in the mitochondria ?
Combustion reactions occur
They convert the energy that comes from the environment to make it usable by the cell (like a power plant)
What is the mitochondria similar to and why?
It generates chemical energy like a battery
What is the energy made by the mitochondria?
A form of chemical called adenosine triphosphate (ATP)
What is ATP?
Adenosine triphosphate
An energy currency that every cell in our body can use and it keeps us alive
What is the lysosome?
a small membranous sac filled with enzymes. It is created by the rough endoplasmic reticulum
What does the lysosome do?
Helps to digest certain nutrients and to break down and recycle certain constituents of the cell
What is DNA, what does it contain?
Deoxyribonucleic acid
It contains the genetic code that contains all the hereditary information of an individual. It is the basic unit of genes
What structural units are DNA composed of?
Nucleotides
What is each type of nucleotide composed of
A nitrogenous base
A sugar
A phosphate group
What are the four types of DNA forming nitrogenous bases ?
Adenine (A)
Guanine (G)
Thymine (T)
Cytosine (C)
What are the complementary pairs?
Adenine with thymine (A-T or T-A)
Guanine with cytosine (G-C or C-G)
What is DNA?
A very long molecule containing thousands of genes
Information center for the construction, repair, function and duplication of the cell
Which go together
A <
T >
C (
G )
What is a genome ?
all genetic information of an individual or a species
What is a gene ?
A segment of DNA in which we find genetic info that allows the production of a particular molecule or that determines a specific characteristic. This gene occupies a precise position in a chromosome
What is the role of genes?
Determine physical appearance
Functioning of cells ex: we find the “recipes” for the production of protein
Can genes be defective ? What happens if so ?
Greens can be defective, in this type of situation an individual is often sick.
Ex: cystic fibrosis
Epilepsy
Certain cancers
How many chromosomes do humans have?
Two pairs of 23
46
