Cells Flashcards
Unicellular organism
An organism made up of only one cell.
Multicellular organism
An organism made up of many cells.
Name a piece of equipment used to see cells:
A microscope.
What is the function of a microscope?
To magnify an image.
What part of a microscope magnifies the image?
The objective lens and the eyepiece lens.
Why does the specimen need to be very thin?
So that light is able to travel through it.
Why might a coloured dye be added to the specimen?
To stain it to make it easier to see.
On what part of a microscope is the slide placed?
The stage.
How is the total magnification of the image calculated?
Total magnification = eyepiece lens magnification x objective lens magnification
What are the components of a plant cell?
Cell membrane, cell wall, cytoplasm, nucleus, mitochondria, chloroplast, vacuole.
What are the components of an animal cell?
Cell membrane, cytoplasm, nucleus, mitochondria.
What three components of a plant cell are not present in an animal cell?
Cell wall, chloroplast, vacuole.
Cell membrane
Controls what comes into and out of the cell.
Nucleus
Controls the cell and contains genetic material.
Mitochondria
This is where respiration happens – release energy for the cell.
Cytoplasm
Where most of the chemical reactions take place.
Cell wall
Is rigid so it strengthens the cell.
Chloroplast
This is where food is made for the plant by photosynthesis.
Vacuole
Contains a watery liquid called cell sap that keeps the cell firm.
What is the function of a nerve cell?
To carry electrical messages around the body.
Describe how the nerve cell is specialised to perform its function:
It is long, thin and has connections at each end.
Explain how a nerve cell is specialised to perform its function:
Long – to allow messages to travel to different parts of the body
Connections – to connect with other nerve cells to pass messages on.
What is the function of a red blood cell?
To transport oxygen around the body to all cells.
Describe how the red blood cell is specialised to perform its function:
It contains haemoglobin, has no nucleus and has a disk-like shape.
Explain how a red blood cell is specialised to perform its function:
Haemoglobin – oxygen joins to this chemical inside the cell
No nucleus – more space for haemoglobin
Disk-like shape – Increases surface area for carrying oxygen.
What is the function of a sperm cell?
To carry male genetic material to the egg cell.
Describe how the sperm cell is specialised to perform its function:
Has a long tail
Has a streamlined head
Contains lots of mitochondria
Explain how a sperm cell is specialised to perform its function:
Tail – allows it to swim towards the egg
Streamlined head – allows it to move faster
Lots of mitochondria – to release lots of energy for moving.
What is the function of a leaf cell?
To make food for the plant by photosynthesis.
Describe how the leaf cell is specialised to perform its function:
Contain lots of chloroplasts.
Explain how a leaf cell is specialised to perform its function:
Lots of chloroplasts – to absorb more energy to carry out photosynthesis.
What is the function of a root hair cell?
To absorb water and nutrients from the soil.
Describe how the root hair cell is specialised to perform its function:
Has a long, thin root hair
Do not contain chloroplasts
Explain how a root hair cell is specialised to perform its function:
Root hair – Creates a larger surface area to allow more water to enter the cell.
No chloroplasts – There is no light underground so photosynthesis will not happen in the cell.
Name two unicellular organisms:
Amoeba and euglena
Name the components of an amoeba:
Cell membrane, cytoplasm, nucleus.
How does an amoeba move?
By changing the shape of its body.
Name the components of an euglena:
Cell membrane, cytoplasm, nucleus, chloroplasts, eyespot and flagellum.
How does an euglena move?
The flagellum spins allowing it to move.
How does an amoeba and euglena reproduce?
By binary fission: it splits itself into two cells.
