what are the main features found in all living cel
All plants and Algal cells have:
- a cell wall- made of cellulose (strengthens the cell, gives it suport)
- chloroplasts- contain chlorophyll
- permanent vacuole-space in cytoplasm filled with cell sap
how do plant cells differ from animal cells?
plant cells contain a cell wall and chlorolast where as animal cell doesnt
what is a specialist cell?
a cell that has a specific job.a few examples are;
red blood cell
white blood cell
what is an Enzyme? what does it do?
a biological catalyst
it breaks down large molecules into smaller molecules in the human gut
what is the word equation for photosynthesis?
carbon dioxide+water (arrow) glucose+oxygen
what is the mitochondria?
found in cytoplasm
this is where oxygen is used and most of the energy is released during respiration
what is the ribosome?
this is where proteinsynthesis occurs.
All protein needed to the cells are made here
what is the cell membrane?
controls the passage of substance in and out of the cell
what is the nucleus?
controls the activity of the cell
contains the genetic information
what is the cytoplasm?
a liquid cell where most of the chemical actions needed for life takes place
in a bacteria/yeast cell, what features does it co
what can increase the rate of diffusion? and examp
an area of high concentration and an area of low concentration.
carbon dioxide in the cell- if the concentration gets to high it moves out of the cell and back into the lungs
glucose- if there is a high concetration of glucose outsdie the cell it passes through into the cell
why do some cells contain microvilli?
to increase the surface area of the cell so they can diffuse easily
what are organs? examples of organs?
organs are made up of tissues. one organ can contain several tissues
what are the limiting factors for photosynthesis?
- Light intensity
- carbon dioxide levels
what are proteins? what are they used for?
long chains of amino acids
- structual components such as muscles and tendens
- hormones such as insulin
- antibodies- destroy pathogens
- cataylsts- in forms of enzymes
how are carbohydrates digested?
broken down by enzymes called carbohydrases (Amylases)
how is protein digested?
broken down into amino acids by a cataylst called protease- happens in your stomach, pancreas and small intestines
how are fats digested?
lipids (fats/oils) broken down into fatty acids and glycerol. this reaction is cataylsed by lipase enzymes
what is mitosis?
original cell divide into 2 cells- both exactly the same as the original cell.
- has the same number of chomosomes as original cell
- the cells produced are identical
- used in asexual reproduction or the production of new body cells
what is meiosis?
produces a copy of orginal cell- new cell then separate again- only half of genetic information each.
- half the chromosomes of the orginal cells
- used in sexual reproduction- the new production of gametes
- four cells are produced.cells produced are all equal
what is Heterozygous?
genes are different
what is homozygous?
genes are the same
how did dinosaurs go extinct?
metorite hit mexico and sent shockwaves +sand around the earth in the air, sand blocked the sun causing quick climate change. particles of rock came back to earth as moltern.
what ways can organisms go extinct?
what is natural selection?
"survival of the fittest"
the strongest animals survive while the weaker animals get eaten/killed by predators. the strongest survive and produce- passing on the the strong characteristics.
what is geographical isolation? how are new specie
when a specy is split into 2(or more) different habitats and become isolated from each other. The doffernt groups under go natural selectionto help them evolve to their new habitat.
geographical- when the specie is physically separated. could be due to mountains, rivers and islands
what is a tissue?
a collection of speciallised cells that form to make tissues with a simular function
name 1 type of a plant tissue and its function
mesophyll tissues carries out photosynthesis
what is the active site?
special shape of an enzyme molecule
whats the difference between greenhouse and hydrop
greenhouse- plants are grown in soil and atmosphere is controlled to produce best plants.
hydroponics- plants are grown in water with a perfect balance of mineral ions instead of soil
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