Adaption and inheritance Flashcards
Competition and inheritance
Animals and plants both compete for a limited supply of resources, these resources are needed to enable them to survive and thrive. Look at the selection below and decide which of these animals and/or plants compete for.
Animals and plants who compete for resources need adaptations to help them gain the required resources.
Adaptations are characteristics that enable an organism to be successful and to survive.
This is especially important in inhospitable environments such as the desert or arctic.
Adaptations in the desert
The Oryx is very well adapted to the harsh conditions of the desert.
Wide feet that don’t sink in the sand
Cools down by standing on the top of dunes to catch a breeze
Does not sweat
Eats at night
Concentrated urine and dry faeces
Can survive 10 months without drinking (gets all water from its food)
The cactus is well adapted for survival in the desert.
They have stems that can store water.
Widespread or very deep root systems can collect water from a large area or from very deep underground.
The leaves of the plant are reduced to needle-like structures referred to as spines that limit water loss.
The needle-like leaves act as a self-defence mechanism that protects the plant from predators.
The stem can perform photosynthesis.
The plant is covered with a thick waxy cuticle that helps to conserve water and protect it from desiccation in the scorching heat.
Further adaptations in organisms
https: //sites.google.com/d/1j3nHTilUOmqjynmtjzARVeIEXYiUCIlW/p/1pK_lTJ3gbJB6SX01wbg-o66Ab9L7emP3/edit
https: //sites.google.com/d/1r07btdAOfrlGBBItjtfwaIqUe6zAYaNa/p/1cHNf78cvFihr6PSNZNWO06bcvqHygBZ0/edit
Adaptations to change
Most adaptations are very slow to appear and are not an instant process. A number of adaptations are a result of climate change, an adaptation that may be useful in cold weather may be a hindrance in hot weather.
Trees adaption to change:
We can clearly see trees adapting to change, most deciduous trees lose their leaves in the winter when there is less sunlight and the season becomes cold. By losing their leaves they are saving energy, the fallen leaves at the base of the tree provide a small layer of insulation around the roots and once decomposed the tree can re-use
some of the nutrients.
Evergreen trees are adapted to lose less water, this enables them to keep their leaves all year round.
How do animals cope with colder seasons?
Hibernation: sleeping throughout winter and conserving energy
Migration: move somewhere warmer with more food or potential mates
Thicker fur: sheep grow a thick coat over winter to keep them warm
Adaptations- polar bear
https://docs.google.com/document/d/1GiXIa4rE6tPGySnPO-X45hMpIFeZxMXLw_HBTXR9aWA/edit
Predator prey relationship
Some predators feed off just one type of prey, this is known as interdependence. This is where the change in one population for one organism directly affects
the population of the other
organism.
When the prey (hare) population increases, the predators (lynx) have more to eat. The lynx survives longer and reproduces more
This increases the number of predators
The growing predator population eats more prey. The prey numbers decrease
Soon there is not enough food for the predator population so their numbers decrease
There are fewer predators feeding on the prey, the prey population increases
The cycle starts again
What is a species?
A group of similar organisms which can reproduce and produce fertile offspring is called a species.
Different species have obvious differences, but, animals within a species have less obvious differences.
The differences within a species are called variation
There are many different types of variation including…
- Mass/Weight
- Height
- Skin colour
- Eye colour
- Typical health conditions
- etc
What causes variation?
Variation can be inherited from parents (genes, passed down) or can be caused by environmental factors (comes from external forces).
Inherited variations in humans include sex, eye colour, blood group, the ability to roll your tongue, a beard etc
Environmental variations include things like injuries, hair colour if dyed, viral illness and many more.
However, things like weight, strength, intelligence and height can be an inherited variation, an environmental variation or both.
More variation examples
The Alaskan malamute is considered to be a dog breed closely related to wolves. The Shiba Inu is a different breed of dog and also related to wolves but not as closely. What is the difference between breed and species?
A species is a group of similar organisms that can breed to produce fertile offspring. A breed is a noticeable variation in a species this means that two different breeds of the same species could still reproduce.
Blood types
Humans have 8 different blood types- A+, A-, B+, B-, AB+, AB-, O+ & O-….
O- is a compatible with all blood types
Different letters mean the red blood cells have different antigens but as O has no antigens it is compatible with all other blood types. This is because the body doesn’t recognise the antigens as a threat as it has none.
O- is compatible with all blood types while O+ is compatible with all positive blood types.
O used to be called C however, the name was changed to indicate the uniqueness of this blood type.
Continuous variation
Human height is an example of continuous variation because it ranges from that of the shortest person in the world to the tallest person. Any height is possible between these values. So it is a continuous variation.
Other examples include…
- Weight
- Arm span
- Finger length
- Head circumfrence
- Heart rate
- Earlobe shape
Discontinuous
Discontinuous data is a characteristic with a limited number of possible values examples are…
- Sex
- Blood group
- Eye colour
Inheritance
Parts of the human body…
smallest- - DNA - Nucleus - Cell - Tissue - Organ - Organ system - Body biggest
- A Chromosome is bigger than a gene
Definitions:
Gene- a gene is a section of DNA that holds the information to produce a characteristic.
Chromosome- A chromosome is a long strand of DNA that contains many genes.
Nucleus- A nucleus is a part of the cell when DNA is stored.
DNA- DNA is a chemical that contains all the information needed tto make an organism.
DNA & Chromosomes
DNA (deoxyrionuclecic acid) contains all of the information to make an organism and is shaped like a double helix.
DNA is arranged in long strands called chromosomes, on each chromosome there are thousands of genes.
Each gene will fully or partially code for a characteristic.
Nearly all human cells contain a set of chromosomes = 23 pairs of chromosomes or 46 chromosomes.
The number of chromosomes can differ depending on the species, cats have 19 pairs and a type of fern has 610 pairs.
The world record holder for most chromosomes is the fern ophioglossum reticulatum with 1260 chromosomes.
People with down syndrome have one extra chromosome.
Half of your chromosomes will come from your mother from an egg cell and the other half from your father’s sperm cell.
Both an egg cell and a sperm cell contain 23 chromosomes and when fused during fertilisation they will form an embryo with 23 pairs or 46 chromosomes.
