Organisation Flashcards
What changes occur when a cell differentiates?
- It may change shape
2. Different sub cellular structures develop to let it carry out a specific function
What are the adaptations and functions of a sperm cell? [4]
- Many Mitochondrion=> provides energy through respiration for their journey
- Tail=> propels sperm to fertilise the egg
- Acrosome=> contains enzymes to allow sperm to penetrate the outer layer of the egg
- Nucleus=> contains only one set of chromosomes
What are the adaptations and functions of a muscle cell? [2]
- Protein fibres=> allows for contraction
2. Many Mitochondrion=> provides energy for contraction
What are the adaptations and functions of a nerve cell? [2]
- Long Axon=> allows electrical impulses to be transmitted around the body
- Dendrites=> increase surface area so can connect to other nerve cells easily to transmit impulses
What are the adaptations and functions of a red blood cell? [2]
- Lack of organelles=> more room for haemoglobin
2. Bi-concave shape=> increased surface area for oxygen absorption
What are the adaptations and functions of Xylem? [2]
- Made up of dead cells forming a long hollow tube
- strengthened by lignin
- to transport water from roots to leaves (one way)
What are the adaptations and functions of Phloem?
- Arranged end to end forming tubes=> allows sugar through
- contains companion tubes
- Transports sugar around the plant
What are the adaptations and functions of Root hair cells? [2]
- Many Mitochondrion=> provides energy for active transport of minerals
- Long projection=>increase the surface area to absorb water and minerals
Muscular tissue
Contracts to allow movement
Glandular tissue
Produces substances such as enzymes and hormones
Epithelial tissue
Covers organs
Muscular tissue (in the stomach)
Churns the food
Glandular tissue (in the stomach)
Produces digestive juices
Epithelial tissue (in the stomach)
Covers the outside and inside of the stomach
Tissue
A group of cells with a similar structure and function which work together to do a job
Organ
A group of tissues which work together to preform a specific job
Organ system
A group of organs working together to do a particular job
Organism
A group of organ systems working together
What is the role of an Enzyme? [2]
- A biological Catalyst
2. Speeds up chemical reactions without taking part
What are the properties of an Enzyme? [3]
- Large protein
- Catalyse specific reactions
- Work best at a optimum pH and Temperature
The ‘Lock and key theory’? [3]
- Enzymes have a specific active site (lock)
- Chemical called a substrate (key) binds to a specific enzyme active site
- The reaction is catalysed and products are released
What is denaturing? [2]
- Extreme pH and/or temperature causes the active site of the enzyme to change shape
- Substrates can no longer fit inside=> reactions cannot be catalysed
What do digestive enzymes do? [3]
- Pass out of cells into digestive system to make contact with food molecules
- Break down large molecules into smaller molecules
- These can now be absorbed into the bloodstream
What are the 3 digestive enzymes?
- Amylase
- Protease
- Lipase
Where is Amylase produced?
- Salivary glands
- Pancreas
- Small intestine
Where and in what conditions is Protease produced?
- Stomach=> hydrochloric acid (acidic condition)
- Pancreas
- Small intestine
Where and in what conditions is Lipase produced?
- Pancreas
2. Small intestine (Bile=>alkaline condition)
What does Amylase do?
Starch=> sugars
What does Protease do?
Protein=> Amino acids
What does Lipase do?
Lipids=> glycerol and fatty acids
In what ways does Bile help enzyme digestion? [2]
- Neutralises hydrochloric acid from stomach=> optimum pH for enzymes
- Emulsifies large fat droplets to smaller fat droplets=> larger surface area for enzymes to work on
Where is Bile produced? [2]
- Produced in the liver
2. Stored in the gall bladder
What is blood? [2]
- A tissue
2. Made of a liquid called plasma
What are the functions and adaptations of Plasma? [2]
- Transports dissolved substances around the body, e.g. Glucose, antibodies, urea
- Liquid => blood cells can float
What are the functions and adaptations of Red blood cells? [3]
- Transports oxygen around the body
- No nucleus, bi-concave shape
- Contains haemoglobin which binds to oxygen
What are the functions and adaptations of White blood cells?
- Changes shape=>Ingests pathogens
- Release antibodies
- Releases antitoxins
Platelets
Fragments of cells=> collect at wounds=> Helps blood clot
What are the adaptations and functions of Arteries?
Thick muscular walls=> withstand high pressure=> carries blood away from the heart
What are the adaptations and functions of Veins?
- Thin walls and wider lumen=> carries blood to heart
2. Valves prevent black flow of blood
What are the adaptations and functions of Capillaries?
- Thin walls one cell thick=> quick diffusion
2. Transports substances from the blood to the cells
Why is the heart called a double pump?
- Left ventricle pumps blood around the rest of the body
2. Right ventricle pumps blood to where gas exchange occurs
What is the job of the left side of the heart?
Pumps oxygenated blood to rest of the body=> glucose+ oxygen to cells
What is the job of the right hand side of the heart?
Pumps deoxygenated blood to the lungs where it collects oxygen
Why is the left hand side thicker than the right hand side
- It has to pump blood around the body
2. At high pressures
What is the job of values in the veins?
Prevents backflow of blood
What is the job of values in the veins?
Prevents backflow of blood
Left side of the heart [4]
- Oxygenated blood enters the pulmonary vein
- Into left atrium and left ventricle
- Out of the aorta
- To the body cells where substances such as oxygen and glucose are delivered to the cells
Right side of the heart [4]
- Deoxygenated blood enters the vena cava
- Into the right atrium and right ventricle
- Out of the pulmonary artery
- To lungs where it collects oxygen and becomes oxygenated blood
How is the resting heart beat controlled?
By a group of cells in the right atrium acting as a pacemaker
What are the adaptations and functions of alveoli? [3]
- Large, moist surface area
- Very rich blood supply=> concentration gradient
- Close to capillaries=> short diffusion distance
- Exchanges oxygen and Co2
Describe the route of oxygen through the lung? [4]
- Air travels through nasal cavity to the trachea
- They travel through one of two bronchi
- These divide to bronchioles
- They then exchange in the alveoli
What are the adaptations of the trachea?
- They have rings of cartilage to prevent collapse
What are the consequences of Coronary Heart Disease? [4]
- Layers of fatty material build up in coronary arteries
- Blood vessels become narrow
- reduce blood flow
- Lack of oxygen for the heart muscle
How do Stents work? [2]
- Keep artery open
2. Blood can pass through
How do Statins work? [2]
- Reduce blood cholesterol level
2. Slow down build up of fatty material
How do Artificial pacemakers work?
- Corrects irregularities in heart rate
What are the advantages of Stents? [4]
- Will remain in place for a long time
2. Rapid recovery time
What are the disadvantages of Stents? [3]
- Risk of infection from procedure
- Risk of surgery, e.g. heart attack
- Risk of blood clot
What are the advantages of Statins?
- No need for invasive procedure
What are the disadvantages of Statins?
- Regular dosage of drugs required
- Side effects of drugs
- Takes awhile for effects of drugs to happen
What are the advantages of Artificial pacemakers?
Improves quality work and length of life
What are the disadvantages of Artificial pacemakers?
Regular medical check-ups required
Describe Inhalation [6]
- Air is drawn into the lungs
- Ribs move upwards and out
- Volume of the chest increases
- Pressure inside the chest decreases
- Intercostal muscles contracts
- Diaphragm flattens
Describe Exhalation [6]
- Air is forced out of the lungs
- Ribs move downwards and in
- Volume of the chest decreases
- Pressure inside the chest increases
- Intercostal muscles relax
- Diaphragm moves upwards
Non communicable disease
Non communicable diseases cannot be spread between organisms
Casual Mechanism
Explains how one factor influences another biological process
What are the effects of exercising? [3]
- More muscle tissue=> increases metabolic rate
- Reduces risk of developing arthritis, high blood pressure and diabetes
- Lowers cholesterol level
Benign tumours
Growth of abnormal cells which stay in one area within a membrane
Malignant tumours [3]
- invade neighbouring tissues
- Spread to different parts in the blood (secondary tumours)
- Cancer cells live longer
What are the causes of cancer? [2]
- Genetic and lifestyle risk
2. Uncontrollable cell growth and mitosis
What are the effects of ionising radiation? [3]
- Ionising radiation is a carcinogen that can cause cancer
- Radiation penetrates the cell
- Causing mutation
What is the function of the Epidermis?
Covers the outer surfaces of the plant for protection
What is the function of the palisade mesophyll?
The main site of photosynthesis in the leaf
What is the function of spongy mesophyll?
Air gaps between cells allow gasses to diffuse
Describe the route of water in a plant [2]
- Water and minerals are transported up xylem
2. At the leaves most of the water evaporates and diffuses through the stomata (Transpiration)
What are the factors affecting rate of transpiration?
- Increase in temperature=> more energy to the water=> evaporation
- Faster air flow (wind)=> blows away water vapour=> allowing more to evaporate
- Increase light intensity=> stomata open
- Increase humidity=> reduces concentration gradient slowing transpiration
Why do stomata close at night?
Carbon dioxide is not needed for photosynthesis so Stomata are closed to prevent water loss
How do Stomata open?
- Guard cells absorb water when plentiful
- This causes them to bend
- Gases are allowed in and out for photosynthesis and water for transpiration
Why are stomata usually found on the bottom of a leaf?
The sun doesn’t directly shine on it, reducing water loss
What is translocation? [2]
- Phloem tissue transports dissolved sugars from the leaves to the rest of the plant
- The movement of food is translocation