Biology Flashcards
Give 3 relationships Between Organisms.
Organisms are dependent on one another for these reasons
1) provide a food source (any organism that is consumed).
2) They help with pollination (insects such as bees).
3) They help provide shelter (some species of tree).
Some organisms can affect their environment and often impact other species negatively.
Give an example
When a species over hunts a particular population causing them to die out - this can have implications for other organisms.
Give 4 examples of impacts that humans have on the environment
1) If pollutants from humans make it into the environment, this can cause an accumulation of toxins in certain apex predators.
2) This can kill the predators.
3) Pollution can also affect habitats such as acid rain killing forests.
4) Large-scale destruction of habitats (e.g. cutting down a rainforest) can have a huge effect on the organisms who live in that environment.
Name 5 organelles in an animal cell and explain their function.
1) The cell membrane controls what can go into or out of the cell.
2) The nucleus controls the cell and holds all your genetic material. Your genetic material is called your DNA.
3) The cytoplasm is a jelly-like substance, where the chemical reactions happen inside cells.
4) Mitochondria use up oxygen and nutrients, such as sugar, in order to release energy in respiration.
5) Ribosomes are tiny structures where protein synthesis occurs.
Name 8 organelles in a plant cell and describe their function
1) The cell wall gives the plant cell structure and protection, made from cellulose.
2) Vacuoles contain cell sap and can store sugar that has been made from photosynthesis.
3) The chloroplasts contain chlorophyll, which absorbs light energy for photosynthesis, and contains enzymes for photosynthesis.
4) The cell membrane controls what can go into or out of the cell.
5) The nucleus controls the cell and holds all your genetic material. Your genetic material is called your DNA.
6) The cytoplasm is a jelly-like substance, where the chemical reactions happen inside cells.
7) Mitochondria use up oxygen and nutrients, such as sugar, in order to release energy in respiration.
8) Ribosomes are tiny structures where protein synthesis occurs.
What is diffusion?
Substances can enter and leave cells in a process called diffusion. They move from areas of high concentration to areas of low concentration.
What are cells adaptations?
Cells are adapted to do a particular role for a certain purpose.
This is why life on earth has evolved.
What is a flagellum and what type of cells have them?
A flagellum is another word for a tail.
Flagella help some single-celled organisms move around the habitat, lets them find food, move to more favourable conditions, or avoid being eaten.
what is a cell?
The basic building block of all organisms.
what is an organelle?
A specialised unit within a cell which performs a specific function.
What is a tissue?
A group of cells working together to perform shared function, often with similar structure. e.g muscle
What is an organ?
A structure made up of groups different tissues, working together to perform specific functions
What is an organ system?
A group of organs with related functions, working together to perform certain functions within the body.
What is an organism?
When more than one organ system work together to perform a job.
How do muscles work?
Muscles work by contracting and relaxing.
What are antagonistic muscles?
In an antagonistic muscle pair, one muscle contracts and the other relaxes or lengthens.
the muscle that contracts is called the agonist.
the muscle that relaxes or lengthens is called the antagonist.
Name the 5 Functions of the skeleton
1) Movement- bones act as levers and form joints.
2) Protection and support - hard bone protects soft tissues underneath
3) blood cell production in the bone marrow.
4) storage of minerals - bones are made up of and store calcium and phosphorus, which can be used in other parts if the body if required.
5) attachment of muscles. bones provide surfaces for the attachment of muscles.
What are connective tissues?
Ligaments connect bone to bone L B B
tendons connect muscle to bone.
cartilage prevents bones from scratching. found on the end of bones.
Tendons connect bone to muscle T B M
Identify the 6 Components of a balanced diet.
1) Carbohydrates- starches and sugar
2) Lipids (Fats)- oils and fats
3) Protein- made of amino acids
4) Water
5) Fibre- indigestible plant material
6) Vitamins- organic
Minerals- inorganic
Explain the role of the Components of food
Carbohydrates - a slow release energy source.
Lipids (fats) - a fast release energy source.
Proteins - for growth and repair of tissues.
Vitamins - help prevent deficiency diseases.
Minerals - are needed for key chemical processes in your body.
Fibre - helps keep you regular and avoid constipation.
Water - so that you can stay hydrated.
Deficiency diseases
Scurvy comes from not eating enough vitamin C. It causes issues in your connective tissues.
Rickets comes from not eating enough vitamin D which is vital for bone development so not consuming enough leads to a softening of your bones. Rickets gives you bowed legs.
Goitre comes from not eating enough iodine. The thyroid gland in your neck swells up.
Anaemia comes from not eating enough iron. It is where you don’t have enough red blood cells. Iron is a key component of haemoglobin, the chemical that transports oxygen around your body. This is why blood has a metallic taste.
Factors which affect the amount of food you need
Gender
Age
Energy levels - amount of exercise
Average calorie requirement for adults
Men 2500 kcals
women 2000 cals
Women 2000 kcals
Define digestion
Breaking down the food you have taken in into small and soluble molecules that can be taken in and processed by the body.
What substances enable digestion
Enzymes, which are biological catalysts, help chemically break down the food on its journey through the digestive system.
What are the roles of the mouth and oesophagus in digestion.
The mouth is responsible for mechanically breaking down the food (chewing) as well as releasing some enzymes stored in your saliva - amylase
The oesophagus or gullet transports food from the mouth to the stomach.
what was the role of the stomach in digestion?
The stomach’s muscular walls contract to mechanically digest the food.
An enzyme is produced to break down proteins - pepsin.
Hydrochloric acid is secreted that kills pathogens and provide correct environment for pepsin.
What are the parts of the intestine and what so they do?
The small intestine contains more enzymes.
this is where digested food is absorbed into the blood stream.
The large intestine is where water absorption happens.
The rectum is where waste material (faeces) is stored.
The anus is muscular tissue that acts as the opening to the outside, when faeces leave the body.
what is the role of the pancreas?
produces pancreatic juices, which contain lots of digestive enzymes which are released into the small intestine.
what is the role of the gall bladder?
stores and releases bile (alkaline) - made in the liver.
bile neutralises stomach acid and emulsifies fats.
What is gaseous exchange in animals?
Oxygen passing into the blood and carbon dioxide passing out of the blood.
To exchange gases with the environment, animals have lungs.
The lungs exchange waste carbon dioxide for oxyen from the air.
The oxygen and carbon dioxide are transported to the body in the blood.
Gaseous exchange also happens in the muscles and organs which use the oxygen and diffuse carbon dioxide back into the blood to return to the lungs to be exhaled
What are the parts of the respiratory system
The nose/ mouth
The trachea.
The bronchus.
The bronchioles.
The lungs.
The alveoli.
The diaphragm
What is ventilation?
Process of breathing in and out in mammals.
Breathing out- exhalation
Describe inhalation
Air is inhaled through the mouth or nose.
The diaphragm contracts and moves downwards.
The ribs move up and out as intercostal muscles contract.
The volume of the chest increases.
The increased size of the chest decrease the air pressure inside which sucks air into the lungs.
Describe exhalation
The diaphragm relaxes and moves upwards.
The intercostal muscles relax so the ribs move down and in.
The volume of the chest decreases, which increases air pressure in the lungs -
forcing the air out.
What is gaseous exchange in plants
Carbon dioxide in oxygen out
Plants need to take in carbon dioxide so that they can photosynthesise. They also produce excess (too much) oxygen in the same process that must be released.
Describe how gaseous exchange occurs in plants?
Carbon dioxide moves from the air into the leaf diffusing through small pores called stomata.
At the same time oxygen moves out of the leaf through the stomata.
what is the role of guard cells?
Guard cells use osmotic pressure to open and close stomata, regulating the amount of water and solutes within them.
What is sexual reproduction
The fusing of different cells to form a new life.
What are gametes?
The cells that are given from each partner.
In humans, the male will supply a sperm cell and the female will supply an egg cell.
In plants the male gamete is pollen the female is the egg
