SCIENCE CELLS Flashcards
What is a cell wall
a cell wall is a touch covering around plant cells, bacteria cells, fungi cells and some Protista cells is the cell wall. It gives plant cells the strength to hold them in shape. Plant cells are made from a substance called cellulose. Water and dissolved substances can pass through cell walls. animal cells do not have a cell wall.
What is chloroplast
chloroplast is found in plant cells and some unicellular organisms. Chloroplast are oval shaped organelles that are mostly found in plant cells. They have a green substance called chlorophyll. Chloroplast use energy from the sun to make food this is also called photosynthesis. Chloroplast is not found in all plant cells only ones in stem and leaf cells.
What are ribosomes
ribosomes is what proteins are made up of.They make up hair and nails, they are found in blood to help transport oxygen. found in plant and animal cells.
What is golgi apparatus
golgi apparatus functions as a factory that protiens received from ER are further processed and sorted for transport. found in plant and animal cells.
What is the role of Mitosis
a cell that duplicates all of its contents including its chromosomes and splits to form two identical daughter cells.
What is the surface of a cell
the surface of a cell is called a cell membrane and a cell membrane acts as a barrier to allow substances in and out like oxygen and waste.
if the cell is to large the substances would not be able to reach all parts of the cell due to large volume to surface area.
Organisation of levels of multicellular organisms(most complex to less)
system
organs
tissue
cell
organelle
What is mitochondria
mitochondria makes energy for the cell through a process known as cellular respiration. found in plant and animal cells
What is a Vacuole
a vacuole stores water, waste and nutrients. Usually a plant cell has a larger vacuole. A vacuole helps mantain their shape.
What is the difference and similarities between a eukaryotic cell and a prokaryotic
a eukaryotic cell contains a nucleus and is multicellular has a cell membrane and other membrane bound organelles.
a prokaryotic cell doesnt contain a nucleus is unicellular and does not contain other membrane bound organelles.
they both contain ribosomes and a cell wall.
Nerve cells
A long thin fibre that quickly carry’s messages from one cell to another
Sperm cell
A long tail that helps it to swim towards the egg cell
Muscle cell
contains fibers that contract and relax
Skin cell
A flat cell that lines the outside surface of your body
Red Blood Cell
A very tiny cell that loses their nucleus when mature then more room is allowed to carry more oxygen throughout the body
Guard cell
kidney shaped cell that can change shape to either close or open a small hole between them which allows gas exchange between the plant and its environment.
Phloem cells
Sieve like cells that form tubes that carry food made in leaves to other parts of the plant
Xylem cell
thick walled cells that carry water up the plant to the leaves
Root Hair cells
cells with small hair that can increase their surface area so they can absorb more water
Leaf cell
function is to photosynthesis so is packed with chloroplast
Epidermal cell
found on the outside of the plant to protect cells underneath and is a flat cell and transparent to allow light in.
cellular respiration
A chemical process that converts glucose and oxygen to energy, water and carbon dioxide. all living things carry out this process.
Electron microscope
was built in 1931 by Ernest ruska and max knoll
some disadvantages were the vacuum and the heat
TEM- transmission electron microscope shows the internal structure of cells
SEM- scanning electron microscope shows images of surface features.
Difference and similarities between fungal cells and plant cells
They both contain a nucleus and both eukaryotic. however plant cells have chloroplast. and plant cells have a cell wall made out of cellulose and fungal cells have one made out of chitin.
Why are cells so small
cells need to be small because they need to be able to quickly take in substances needed and remove waste.
the bigger the cell the longer this process would take.
History of cells
in 1665 robert hooke was using magnifying lenses to look at thin slices of cork, when doing this he saw box-like shapes and decided to call them cells
Field of view
the field of view gets larger when the magnification decreases
the field of view gets smaller when the magnification increases
What are cells
cells are the basic building blocks of all living things
Cell theory
- cells make up all living things
- Cells are the basic building blocks of all living things.
- all new cells are produced by pre existing cells
What is resolution
resolution is what we can see, separate and distinguish between to separate structures that are positioned together
higher resolution=more image detail.
Millimeters, Micrometers, Nanometers
millimeters is 1 thousandth of a metre, micrometers are 1 millionth of a metre, and nanometers are 1 billionth of a metre.
How do you calculate magnification
The eyepiece lens times the objective lens to give the total magnification
Endoplasmic Reticulum
Rough ER
- Contains ribosomes
- used to make and transport proteins
Smooth ER
- No ribosomes
- used to produce fat for the cell
- transports substances
found in plant and animal cells
Light microscope
Binocular- uses 2 eyes
Monocular- uses 1 eye
stereo microscope- a type of microscope that allows us to see detail of much larger specimen
What is the difference between a light microscope and an electron
a light microscope uses light rays while an electron uses small particles of electron to illuminate the specimen being viewed
Organisms
Organisms can be one cell unicellular or different types of cells multicellular. these cells have organelles that perform a specific function to keep the organism alive
Multicellular
Many different types of cells that have different jobs. Each cell will be structured differently to suit its role. this could change in the number of a particular organelle
Rules when drawing
- Draw only few cells
- Use pencil
- Label diagram
- Record magnification
- Do not shade
Unicellular
Unicellular organisms need to be able to carry out all process themselves. They also need to reproduce by themselves by dividing into two ( a half) a process called Binary Fission
Nucleus
Contains DNA and controls the cell growth and instructs to replicate in plant and animals
How to tell if a cell is a plant or an animal
A plant cell has a larger vacuole, has a cell membrane and a cell wall and chloroplast.
An animal cell has a smaller vacuole and just a cell membrane.
Stage
A platform where the slide is positioned with clips to hold it in place.
Light source
A bulb that projects light up through the slide to the eyepiece.
Eyepiece
The lens that the operator looks through.
Body tube
A tube that the eyepiece and nosepiece are attached to.
Adjustment knob
Move the stage up or down and assists in focusing; can be coarse or fine.
Objective lens
Lenses used to see the detail of the specimen; can be low power or high power.
Base
Supports and stabilises the microscope.
Arm
Holds the body tube and can be used as a handle for holding the microscope when carrying.
