Cell structure Flashcards
What is the difference between a prokaryotic and eukaryotic cell?
A eukaryotic cell contains membrane bound organelles whereas a prokaryotic cell contains no membrane bound organelles
What are common cell components in all living things?
DNA, cytoplasm, cell membrane and ribosome
Why are virus’ not classified as living things?
Virus’ do not contain common cell components, they are acellular and cannot perform MRSGREN without a host
What is an animal cell made up of?
cell membrane nucleus mitochondria Golgi apparatus lysosome rough endoplasmic reticulum smooth endoplasmic reticulum ribosomes
Structure and function of cell membrane?
The cell membrane is made up of mainly lipids and proteins.
It regulates movement of substances in and out of the cell.
It contains receptors on its surface which respond to specific hormones.
(cell signalling)
Structure and function of the nucleus?
The nucleus is a large organelle surrounded by the nuclear envelope (double membrane) which contains pores.
Inside the nucleus is the nucleoplasm, nucleolus and chromatin.
Chromatin is DNA surrounded by proteins called histones.
The nucleus controls cell activity by controlling the transcription of DNA and it contains the (DNA) genes which code for specific proteins
In the nucleolus, mRNA and ribosomes are produced
Structure and function of the mitochondria?
The mitochondria is the site of aerobic respiration, it produces ATP releasing energy.
The mitochondria contains outer membrane, inner membrane ( cristae) and the matrix.
Cristae are folds in the inner membrane which allow for a large surface area for enzymes of respiration
Structure and function of the chloroplast?
The site of photosynthesis, small flattened structure surrounded by a double membrane, contain thylakoid membrane within.
Stack of thylakoid membrane are called grana.
Grana linked together by lamellae.
Structure and function of the golgi apparatus?
A group of fluid filled membrane bound flattened sacs.
It processes and packages new lipids and proteins
Also make lysosomes
Structure and function of the golgi vesicle?
A small fluid filled sac in the cytoplasm surrounded by a membrane and produced by the golgi apparatus.
Stores lipids and proteins produced by the golgi apparatus and transports them out the cell.
Structure and function of the lysosome?
A round organelle surrounded by a membrane.
Contains digestive enzymes called lysozymes. Can be used to digest invading cells or to break down worn out components of a cell.
Structure and function of the ribosome?
Small organelle made up of RNA and proteins, not surrounded by a membrane.
The site where proteins are made
Structure and function of the rough endoplasmic reticulum?
Surface is covered with ribosomes
Folds and processes proteins which have been made at the ribosome
Smooth endoplasmic reticulum?
No ribosomes
Synthesises and processes lipids
Structure and function of the cell wall?
A rigid structure that surrounds cells in plants, fungi and algae.
Supports cell, prevents it from changing shape/shrinking/bursting.
Structure and function of the cell vacuole?
Surrounded by a membrane called a tonoplast, contains Cell Sap (water, sugar, minerals)
Helps to maintain pressure inside the cell and keep it rigid (stops plant from wilting)
(involved in the isolation of unwanted chemicals in the cell)
Difference between plant, algal and fungal cells?
Plant cells = multicellular
Fungal/algal cells = multicellular/unicellular
Plant cell wall = cellulose
Fungal cell wall = chitin
Adaption of the epithelial cells?
Walls of epithelial cells contain finger like projection called villi which increase SA for absorption
The epithelial cells on the surface of the villi contains folds called microvilli which increase the SA for absorption.
Contain lots of mitochondria which provide energy for the transport of digested food molecules into the cell
Cell organisation?
tissue = a group of specialised cells working together to perform a particular function
organ = made of different tissues
organ system = different organs working together
Components of a bacterial (prokaryotic) cell?
cytoplasm (which lacks membrane bound organelles)
smaller ribosomes
single circular DNA molecule that is free in the cell and not associated with proteins
murein cell wall (murein = glycoprotein)
What additional components do some prokaryotic cells have?
one or more plasmids
a capsule surrounding the cell (reduce water loss + protect from phagocytosis)
one or more flagella
Structure of viruses
genetic material (DNA/RNA)
capsid
attachment proteins
