Topic 1- Key Concepts In Biology Flashcards
What’s a prokaryotic cell? Example…
A small simple cell
Bacterium
What’s a eukaryotic cell? Example
Complex cell.
Plant or animal
In which cubcellular structure do most reactions for respiration take place? ( plant)
Mitochondria
Which sub cellular structure maintains the internal pressure of a plant cell?
Vacuole
Similarities and differences between a plant and bacteria cell…
Similarities - both have a cell membrane, cell wall, cytoplasm and ribosomes
Differences- plant cells have chloroplasts and mitochondria but bacteria cells don’t.
Chromosomes of plant cells are contained within the nucleus, however a bacteria’s dna floats freely in the cytoplasm. Bacteria cells have small loops of dna called plasmids.
A- cell membrane, holds cell together and controls what enters or leaves
B- nucleus, contains genetic material that controls activities of the cell
C- ribosome, involved in translation of genetic material and protein synthesis
What’s a ciliated epithelial cells main function?
To move bacteria in one direction
Where are ciliated epithical cells found ?
On the surface of organs
Two functions of an egg cell….
To carry female dna
Provide nutrients to the embryo in its early stages
Why do sperm cells contain a large number of mitochondria?
To provide energy ( from respiration) that the egg needs to swim
Why is it important egg and sperm cells are haploid ?
So when the nucleuses combine at fertilisation the resulting cell with have the right number of chromosomes.
How are ciliated epithecal cells adapted for moving substances?
They have cilia, which beat to move substances in one direction across the surface
Why does the structure of an eggs cell membrane change after fertilisation?
To stop any more sperm getting in and making sure the offspring has the correct amount of dna.
A - the tail, this allows the sperm to swim towards an egg cell
B- acrosome, stores enzymes the sperm needs to digest its way through the membrane off an egg cell
What’s the purpose of the fine adjustment knob on a light microscope?
Focus the lens untill a clear image of what’s on the slide appears
What has a higher resolution and magnification, electron microscopes or light microscopes?
Electron microscopes have both a higher resolution and magnification
How would you put a cover slip onto a specimen on a slide so it’s ready to be viewed under a light microscope ?
Cover slip should be placed at one end of the specimen and put on a mountain needle before being pressed down, ensuring theirs no trapped air left under.
How has electron microscopy increased our knowledge of cells?
Higher resolution and magnification has allowed biologists to see very small structures in cells.for example, internal structures of mitochondria and chloroplasts
Labels of important features
Magnification and scale used
How to calculate magnification of a microscope?
Magnification of microscope = Magnification of eyepiece X magnification of objective
