✅Biology PAPER1 cell biology Flashcards
What is a eukaryotic cell?
Cells with a nucleus example e.g plant and animal cells
What are prokaryotic cells?
Cells without a nucleus e.g bacteria
What is the function of cytoplasm
Chemical reactions take place
What does the cell membrane do
It controls what goes in and out of the cell
What happens in the chloroplasts
Photosynthesis happens and this makes glucose and oxygen for the plant
What happens in mitochondria
Aerobic respiration happens and it transfers energy to cells in order to work
What is the function of the nucleus
Contains genetic material and controls what we sell those
What happens in ribosomes
Proteins are made
What three things are not found in animal cells that are in plant cells
A cell wall, vacuole, chloroplasts
What are light microscopes used for?
To look at large subcellular structures
How do you electron microscopes helped our understanding of subcellular structures
They allow us to see smaller things e.g mitochondria
What is a specialised cell
Cells that carry out a specific function E.G sperm
Name three specialised cells
Sperm cells, nerve cells, muscle cells
How was the sperm cell adapted for its function
It has a tail to swim to the egg, it has mitochondria to provide energy to swim, it has a flat head for efficient movement through the female reproductive tract
What is a Chromosome
Coiled up length of DNA molecules and each of them carry genes
What is the cell cycle
When a cell divides
What are the stages of the cell cycle
Growth, DNA replication, mitosis, cell division
What happens at the growth stage of the cell cycle
The cell grows and increases the amount of subcellular structures
What happened to the DNA replication stage of the cell cycle
The DNA replicates and forms chromosomes that are an exact copy of each other
What happens at the mitosis stage of the cell cycle
Chromosome arms are pulled apart and the nucleus then divides
What happens at the cell division stage of the cell cycle
The cytoplasm and cell membrane divide it then produces two new identical cells
What are stem cells
The cells that are in differentiated but can turn into any type of cell and become specialised
Define diffusion
Diffusion is the movement of particles from a high concentration to a low concentration, down the concentration gradient
Define active transport
Active transport is the movement of particles from a high concentration to a low concentration, against the concentration gradient
Define osmosis
Osmosis is the movement of water molecules across a partially permeable membrane from a less concentrated solution to a high concentrated solution
What is the practical for microscopes
One, had a drop of water into the middle of a clean slide. Two, cut up an onion and take off one Leah. Three, use tweezers to peel off some epidermal tissue from the bottom layer. Four, using the tweezers please the skin into the water on the slide. Five, at the drop of iodine solution, are you doing is a stain and stain can make different parts of cells easier to see. Six police of coverslip on top and try not to get any air bubbles hundred. Seven record what you see
How is a nerve cell adapted to the function
They are long to cover more distance in the body, they have branches at the end to connect to other nerve cells
How does a muscle cell adapt to its function
They are long so they have space to contract, they have mitochondria which provide energy for them to contract
How is a root hair cell adapted to its function
They grow into long hair is that stick out into the soil, this gives the plant a big surface area for absorption of water and mineral ions from the soil
How many copies of chromosomes are there in a human cell
23 pairs
What are the risks involved with therapeutic cloning
You could be infected with a virus and the virus could be passed on to a patient and make them sicker
What are some reasons why people would be against stem cell research
People feel the embryos shouldn’t be used for research because each one can be human life, but I think you’re in patients who are suffering on more important than the rights of embryos, some people think that scientist should be finding other sources of stem cells
How constant cells be used to preserve rare plant species
Copies of the plan can be made by taking stem cells from the meristem of a plant and growing them into new genetically identical plants
Where does diffusion happen
In solutions and gases
What will make the diffusion rate faster
When there is a big difference in concentration, when there is high temperature
What small molecules can fit through cell membranes
Oxygen, glucose, amino acids, and water
What is the practical to observe the effect of sugar solutions
First cut of a potat into cylinders with the same length and width, get two beakers one with pure water and one with A very concentrated sugar solution, measure the mass of each potato cylinder and then put one in each beaker, leave the potatoes cylinders for 24 hours , Then take them out and dry them with a paper towel, measure that matters again, if the mass is increased water has moved into the potato cells, if the mass has decreased water has moved out the potato all cells
How do you hair cells take in minerals using active transport
The concentration of minerals is higher in root cells so the root cells can’t fuse to take minerals they use active transport instead it allows the plant to absorb minerals from a very dilute solution in the soil it moves minerals against the concentration gradient
What is the purpose of active transport in the gut
To allow nutrients such as glucose to move from a lower concentration in the gut to a higher concentration in the blood
give one way in which alveoli are adapted for gas exchange
They have a large surface area, thin walls, good blood supply
