Variation and classification Flashcards
A gene is the basic unit of ……………….
Chromosomes
Genetic variation comes from……….
Genes
Genes are responsible for our characteristics such as eye colour, hair colour etc. we inherit our genes from our parents in the ……………. and ……………..
Sperm
Egg
Our genes are found on structures called ……………… inside the nucleus of every cell.
Chromosomes
What is a gene?
A segment of DNA
An example of environmental variation
If you don’t get enough food you won’t be as tall. If a plant doesn’t get enough light, it can’t grow well.
Odd one out and why?
Height. Weight. Can roll tongue
Can roll tongue
It is only affected by genetic factors- the others are influenced by environmental and genetic factors too.
Odd one out and why?
Hair colour. Gender. Skin colour
Gender
It is only affected by genetic factors. The others are affected by environmental and genetic factors.
Odd one out and why?
Aggressive Horns Resistant to diesese
Horns
It is only affected by genetic factors. The others are affected by environmental and genetic factors.
Odd one out and why?
Accent. Blood group Suntan
Blood group
It is affected by only genetic factors. The others are affected by only environmental factors.
What is the plant kingdom? (4 key things)
Organisms that make their own food from air, water sunlight and minerals in the soil
Body contains cellulose for support
Green (contains chlorophyll)
Stays in one place
Does
What is the animal kingdom (4 key things)
Cannot make their own food (eat plants and animals)
Body does not contain cellulose
Not green (does not have chlorophyll)
Move about
Vertebrates
Name the five groups
Birds Fish Mammals Reptiles Amphibians
Fish (4)
Have gills
Scales
Fins
Cold blooded
Birds (5)
Have wings Beak Feathers Lay eggs with brittle shells Warm blooded
Amphibians (4)
Have moist skin
Live on water and land
Breathe in through their skin in water
Cold blooded
Mammals (3)
Have hair
Give brith to live young
Warm blooded
Reptiles (3)
Have dry scaly skin
Lay eggs with tough shells
Cold blooded
What is a link between genetic variables called and what does it mean
A correlation
When the value of one variable changes the other changes in an expected (predictable) way ie in magnitude (how much) and direction (increase or decrease).
What is ‘variation’?
The differences between members of the same species.
Where are genes located?
On chromosomes in the nucleus of the cell.
What is a vertebrate?
An animal with a backbone (cartilage or bone).
What are Arthropods(3)
An invertebrate animal
with segmented bodies and
hollow jointed legs
=Insect, spider or crustacean
Odd one out and why?
Hair length, arm length, eye colour
Eye colour. It is only affected by genetic factors. The other two are affected by genetic and environmental factors.
What is a species?
A group of organisms with similar features that are capable of interbreeding and producing fertile offspring.
What is variation caused by?
Genetic and environmental factors
What are the 7 invertebrate groups?
Annelids Molluscs Echinodermata Crustaceans Insects Arachnida Myriapods
What are the features of annelids (2)
and give an example
Long body divided into segments,
bristles called chaetae
Eg earth worm
What are the features of molluscs (2) and give an example
Soft body with shell,
live in water and on land
Eg snail, cockles, (and octopus and squid are cephalopod molluscs)
What are Echinoderms? (3)
Star-shaped body,
tough, spiny skin,
live in water
Eg star fish and sea urchins
What are insects (5) and examples?
Body divided into 3 sections:head, thorax and abdomen
3 pairs of jointed legs
Antennae
Body covered by a hard case-like outer skeleton
Eg ladybird, butterfly, fly, wasp, praying mantis, cockroach, beetle, locust
What are the features of arachnids (4) and give an example
Body divided into 2 sections
4 pairs of jointed legs
Antennae
Body covered by a hard outer skeleton
Eg spiders and scorpions
What are Myriapods (4) and an example?
Body divided into lots of sections
Very many pairs of jointed legs
Antennae
Body covered by a hard outer skeleton
Eg centipedes and millipedes
Why do scientists classify plants and animals
There are millions of different species so it’s difficult to name and describe them individually so they are classified into groups similar features
