1.1 + 2.1 +2.2 Flashcards
What does MRS C GREN stand for?
Movement
Reproduction
Sensitivity
Control
Growth
Respiration
Excretion
Nutrition
What are all living organisms composed of?
All living organisms are composed of cells
What do we call single cell organisms?
Unicellular organisms
What types of cells are animal and plant cells?
they are both multicellular organisms
What are specialized cells?
They are cells that are specialized to carry out a specific function.
What are the small structures inside cells?
organelles
Examples of single-celled organisms
bacteria, yeast
Functions and definition of a cell membrane
- forms a boundary between the cytoplasm and the outside of the cell.
- it controls what enters and exits the cell
- it is partially permeable
What does partially permeable mean?
allows the passage of some but not others
Functions and definition of ribosomes
- they are very small particles found in the cytoplasm
- make protein
- determined by genes in the nucleus
Functions and definition of a cell wall
- non-living
- freely permeable
- protects and keeps the shape of the cell
what does freely permeable mean?
allows all substances in
Functions and definition of the nucleus
- contains the genetic information of the cell (in the form of chromosomes)
- determines what the cell makes
- controls the cell’s activities
what are chromosomes?
a thread-like structure of DNA
what are genes?
the basic physical and functional unit of heredity
Functions and definition of the cytoplasm
- watery, jelly-like liquid
- contains the organelles and enzymes
- chemical reactions take place here
what are enzymes
proteins that speed up metabolism
Functions and definition of mitochondria
- carry out the reactions of aerobic respiration
- release energy for the cell
Functions and definition of chloroplasts
- absorbs light and energy to make food during photosynthesis
-contains chlorophyll
what is chlorophyll?
- a green pigment found in plant cells
Functions and definition of a vacuole
-filled with cell sap
- stores dissolved sugars, minerals, ions, and water
- helps keep the cell’s shape
differences of plant and animal cells
animal cells have 5 structures and plant cells have 8
what are red blood cells?
- transport oxygen around the body
- no nucleus
what are guard cells?
- controls opening and closing of stomata (in plants)
what are nerve cells?
- carries electrical impulses around the body
- carrie messages which is why they are long
what are root hair cells?
- absorbs minerals and water from soil
- has large surface area and a thin cell wall
- has no chloroplast (unlike other plant cells)
what is cell differentiation?
the process by which a cell changes to become specialized
what are stem cells?
they are undifferentiated cells that have the ability to become specialized
how can someone get lots of stem cells?
from early human embryos
Can stem cells be used in medicine or research?
Yes. Stem cells can be cloned in a lab and
made to differentiate into specialised
cells to be used in medicine or research.
what happens to stem cells in stem cell therapy?
In stem cell therapy, stem cells have been
injected into damaged tissues to repair
them such as the retina in the eye or
heart muscle.
specialized cells are made through a process called?
differentiation
most multicellular organisms have ?
specialized cells
definition of magnification
the process of enlarging the physical appearance / image of something
What is the formula for magnification?
Magnification = image size / actual size
Formula for total magnification?
multiply magnification of the two lenses together
units are changed by either?
multiply or dividing by 1000
what are scale bars used for?
to show the real length of the magnified images
what do cells need?
oxygen, water, hormones, urea, carbon dioxide, amino acids, glucose
when does diffusion happen?
when a substance is more concentrated in one place than another
difference in concentration is called?
a concentration gradient
what are factors that affect the rate of diffusion?
temperature, distance, concentration gradient, surface area to volume ratio
what else can effect the rate of diffusion? (distance)
-Rate of diffusion is also
dependent on the distance
the particles have to travel.
-The shorter the distance the
faster the rate of diffusion.
when will diffusion happen faster? high concentration gradient or low?
high concentration
diffusion and surface area to volume ratio
the larger the surface area to volume ratio is, the faster the diffusion
what is osmosis?
when water moves from a dilute solution to a. more concentrated one across a partially permeable cell membrane
how to calculate the percentage change in mass?
percentage change in mass = change mass/original mass times 100
what is active transport?
when a cell needs to take in a substance against a concentration gradient.
