Science Unit 1 Flashcards
What does ‘species’ mean?
- Capable of breeding together to produce fertile offspring
- Offspring of two different species are called hybrids & infertile
( •not all hybrids are sterile- many plant hybrids are fertile
•Some organisms produce asexually )
How are organisms classified into groups according to the characteristics they have in common?
Kingdoms:
•Animalia (multicellular, no cell wall or chlorophyll, find food from environment)
- Plantae (multicellular, have chlorophyll & cell wall, make food through photosynthesis)
- Fungi (multicellular, no chlorophyll, cell wall, feed on dead organic matter)
- Protoctista (uni cellular EXCEPT SEAWEED, distinct nucleus)
- Prokaryotes (unicellular, no distinct nucleus)
How to use a key to identify species?
- Descriptions in a key come as opposite statements
* Choosing one statement that fits the species will lead you to the next
Who was the first to explain natural selection?
Charles Darwin and Alfred Wallace
Verification can be caused by..?
Genes
Environment
Genetic disorders can be caused by..?
Changes in genes (mutations)
The cells nucleus contains __________ on which _______ are located, and I understand how forms of genes called _____ lead to differences in inherited _________
- Chromosomes
- Genes
- Alleles
- Characteristics
What does homeostasis mean?
Maintenance of a stable internal environment.
Eg, keeping the right body temperature and amount of water in the body.
What does the central nervous system consist of?
Brain, spinal cord.
Nervous responses can be voluntary or involuntary.
Where are hormones produced?
Endocrine glands and transported to the blood to their target organs.
What does lack of insulin cause?
Diabetes Type 1
What does resistance to insulin cause?
Diabetes Type 2
Plants use hormones to…?
Respond to stimuli such as light and gravity
What is a drug?
A drug is a substance from outside the body that affects the central nervous system and brings about changes in the body that can lead to addiction
How do stimulants affect the brain?
Including caffeine increase the speed of our reactions
How do depressants affects the brain?
Depressants, such as alcohol slow the activity of the brain and reaction times
How do painkillers affect the brain?
Painkillers, such as morphine, Deaden pain or affect the way we think about it
How do hallucinogens affect the brain ?
Hallucinogens, like cannabis, LSD and solvents, produce sensations of false reality called hallucinations.
What are the effects of some chemicals in cigarettes?
Positive correlation was found between the number of cigarettes someone smoked and the risk of dying from bronchiolitis and lung cancer
Harmful effects of alcohol abuse?
Can cause liver disease and brain damage heart disease cancer and raised BP
What are infectious diseases caused by?
Pathogens, Including those in animal vectors
What can help to prevent the spread of infection?
Antiseptics
How is energy transferred ?
Along food chains and between trophic levels
Sources of pollution?
Sulphur dioxide, nitrates and phosphates
What do decomposes do?
Recycle dead organic matter
