Cells Flashcards
Which is bigger - prokaryotic or eukaryotic?
Eucaryotic
What are Eukaryotes?
Organisms that are made up of Eukaryotic cells
What is a Prokaryote?
A single celled organism
Name all of the animal subcellular structures
Nucleus, cytoplasm, cell membranes, mitochondria and ribosomes
What subcellular structures do plants have that animals don’t?
Cell wall, permanent vacuole and chloroplasts
What are the two types of microscopes?
Light microscopes and electron microscopes
How do light microscopes work?
They use light and lenses to form an image of a specimen and magnify it
Why are electron microscopes better than light microscopes?
They have a higher magnification and a higher resolution so that we can see smaller things in better detail
How do you find magnification?
Image size / real size
How are sperm cells specialised?
Long tail, streamlined head, lots of mitochondria and special enzymes
How are nerve cells specialised?
Long and branched connection at ends (so they can forma network)
How are muscle cells specialised?
Long to give space to contract and lots of mitochondria
How are root hair cells specialised?
Big surface area and large vacuole
How are phloem and xylem cells specialised?
Long, joined end to end, xylem are hollow in the centre and phloem have few subcellular structures (so things can flow through)
How many pairs are there of chromosomes in the nucleus?
23
What are chromosomes?
Coiled up lengths of DNA molecules
What mitosis?
The stage of the cell cycle where cells divide
What is the cell cycle?
A series of stages where body cells in multicellular organisms divide to produce new cells
What does the cell have to do before it divides?
grow and increase the amount of subcellular structures, then duplicate the DNA to form X shaped chromosomes
What is diffusion?
The spreading out of particles from an area of high concentration to an area of lower concentration
Finish this sentence: the bigger the concentration gradient
The faster the diffusion rate
How does temperature effect the diffusion rate and why?
A higher temperature will increase the diffusion rate as the particles will be moving faster as they have more energy
Finish this sentence: the larger the surface area
The higher the rate of diffusion
What is osmosis?
The movement of water molecules across a partially permeable membrane from a region of higher water concentration to a region of lower water concentration
Give three examples of where active transport is used
Root hair cells taking in minerals, taking glucose from the kidney tubes and in the gut when there’s a higher concentration of nutrients in the gut than in the blood
