Cells Flashcards
What is a prokaryotic cell?
A cell without a nucleus
e.g. Bacterium
What is a eukaryotic cell?
A cell with a nucleus
e.g. Plant and animal cells
What organelles are in an animal cell?
- Cell membrane
- Cytoplasm
- Mitochondria
- Nucleus
- Ribosomes
What organelles are in a plant cell?
- Cell membrane
- Cell wall
- Chloroplast
- Cytoplasm
- Mitochondria
- Nucleus
- Ribosomes
- Vacuole
What is the Function of the Nucleus?
To control the functions of the cell
What is the Function of ribosomes?
To synthesise proteins
What is the Function of the cell membrane?
To control movement of substances into and out of the cell
What is the Function of the cytoplasm?
To act as the site where most chemical reactions occur
What is the Function of mitochondria?
The location where respiration occurs
powerhouse
What is the Function of the Cell wall?
To strengthen a cell and help it hold its shape
What is the Function of chloropast?
To Act as the site where photosynthesis occurs
What is the Function of the Vacuole?
To keep a cell turgid
to keep its shape
What is the Function of a sperm cell?
To fertilise the female gamete
ovum
What is the Function of a nerve cell?
To pass nervous information to the brain and spinal cord
What is the Function of a root hair cell?
To absorb water and nutrients for the plant
What is the Function of a xylem cell?
To pass water and nutrients one way through a plant.
What is the Function of a phloem cell?
To pass nutrients both ways throughout a plant.
What are the adaptations of a sperm cell?
- Digestive enzymes; to inseminate the ovum
- Flagellum; for movement
- Half the number of chromosomes; to fuse with the ovum.
What are the adaptations of a nerve cell?
- Long; to quickly pass information throughout the body
- Dendrites; to reach different tissues
What are the adaptations of a root hair cell?
-High surface area; improves absorption of minerals and nutrients
What are the adaptations of a xylem cell?
- No end cell walls; creates an unobstructed path for water and nutrients
- Thick cell walls; to keep the structure of the cell
What are the adaptations of a phloem cell?
- Perforated end cell walls; allows for two way movement of nutrients
- Thick cell walls; to keep the structure of the cell
What is the Function of a muscle cell?
To contract
What are the adaptations of a muscle cell?
-Rubbery strands; allows the cell to contract
What is diffusion?
The movement of particles with the concentration gradient through a semipermeable membrane
What is osmosis?
The movement of Water with the concentration gradient through a semipermeable membrane. (diffusion with water)
What is Active Transport?
The active movement of particles against the concentration gradient using carrier proteins
What is an adaption in cells where active transport occurs?
Greater number of mitochondria to provide energy in the form of ATP
What are stem cells?
Undifferentiated cells
In animals what stem cells do we have?
- Adult stem cells
- Embryonic stem cells
What is the function of adult stem cells?
To replace dead differentiated cells
What is the function of embryonic stem cells?
To divide to form all other cells whilst the animal is a blastocyst
In plants what stem cells do they have?
-Meristem cell
What is the function of a meristem cell?
To allow for plant growth throughout its life; found near new growth
What is mitosis?
The process in which a cell divides to produce two genetically identical daughter cells
What happens during mitosis?
The number of chromosomes doubles, the cell divides and two diploid daughter cells are produced
What is meiosis?
The process in which a cell divides to produce four genetically identical daughter cells
What happens during meiosis?
The number of chromosomes doubles, the cell divides twice and four haploid daughter cells are produced
How has the electron microscope better our understanding of cells?
It is used to
study cells in much finer detail. This has enabled biologists to see and
understand many more sub-cellular structures. (high magnification and resolving power)
What is the equation for magnification?
magnification= size of image/ size of real object
How regularly can bacteria divide (binary fission)?
Every 20 minutes
When culturing organisms why should equipment be sterile?
To avoid contamination
When culturing organisms why should the temperature be below 25 degrees and container not sealed (in school)?
To avoid much more harmful bacteria from growing
