Unit 2 Flashcards
Give the term applied to a group of similar cells that carry out the same function.
Tissue.
Give one example of a tissue from each of the following organisms a plant and human.
Plant: Mesophyll, epidermis, xylem, phloem
Human: blood, muscle, nervous
State the meaning of the term organ.
Group of tissues working together
Give one example of an organ from the following organisms. Plant and human.
Plant:leaf stem, root, flour, fruit
Human: Brain, heart, kidney
Give the meaning of the term system
Group of organs working together
Name three different human body systems.
Nervous, circulatory, respiratory, digestive, excretory, reproductive, skeletal
What are the main functions of the nervous system
The nervous system senses the environment, processes information, responds to the environment.
What is the role of the human reproductive system
Produces gametes, allows development of offspring
Give the main functions of the human circulatory system
Transports food, transport oxygen, transport wastes, assists in defence
Explain what is meant by the term specialisation as applied to the development of cells
Cells change structure; to allow them to carry out a particular function
Describe the organisation in the human body with reference to tissues, organs and systems
Cells of the body are organised into tissues; tissues have particular functions; tissues are organised into organ is; organs work together in systems; systems are coordinated to allow survival of the organism
State what is meant by the term specialised, as applied to cells
Structure suited to function
Give the general function of all stem cells
Divide to produce a supply of cells that can then specialise
Name a type of cell that can be formed when an adult human stem cell specialises
Bone cell, muscle cell, skin cell, blood cells
Name the regions of plants where mitosis occurs
Meristems
Give the location of a region of mitosis in a plant
Shoot tip, root tip, vascular tissues in stem or root
Name to plant tissues that can be formed when plant cells specialise
Epidermal, mesophyll
Describe what happens to a stem cell that results in the production of red blood cell in humans
Cell division; loses nucleus; develops haemoglobin; becomes dimpled
Describe the similarities and differences between embryonic and adult stem cells
Similarity – each can divide, both non-specialised; difference – embryonic can become any cell, adult more limited
Describe the ethical issues surrounding research into human embryonic stem cells
Moral principle to improve medicine; moral principle to respect human life; the two principles cannot both be respected in embryonic stem cell research
Name the two parts of the human central nervous system (CNS).
Brain and spinal cord
State how information is passed along neurons
As electrical impulses
State how neurons are linked in the nervous system
Linked at synapses
State the general function of receptors as part of the nervous system
Convert stimuli to electrical impulses
Give the importance of the rapid reflex action in humans
Protection
Describe the role of the central nervous system in humans
Accept information; processes information; response to information
Describe the functions of each of the following parts of the brain Cerebrum, cerebellum, medulla
Cerebrum - reasoning, memory, emotions
Cerebellum - balance, co-ordination of movement
Medulla - control of heart rate, breathing rate and peristalsis
Describe the role of each of the following cell types in the nervous system. Sensory neurons, relay neurons, motor neurone
Sensory neurons carry electrical impulses to the central nervous system.
Relay neurons transmit electrical impulses from sensory neurons to motor neurone.
Motor neurones transmit electrical impulses to the effectors
Describe what happens when an electrical signal arrives at a synapse.
Transmitter molecules are released into gap at synapse; receptors of the next neuron are affected; electrical impulse moves on
Describe the flow of information along a reflex arc
Stimuli affect receptors; electrical impulses pass through sensory neurons; processed by relay neurons in spinal-cord; electrical impulses sent to effectors; effectors make response
State the function of the endocrine glands
To produce and secrete hormones into the bloodstream
Give two examples of endocrine glands in humans
Pancreas, adrenal, Pituitary
State how hormones carry their messages around the body
Dissolved into the bloodstream
Give the term applied to cells contain receptors sensitive to a specific hormone
Target cells
Name to hormones involved in the control of blood glucose concentration
Insulin, glucagon, adrenaline
Give a reason for the increase in individuals with type two diabetes
Increased life expectancy: increased consumption of sugar; increase in sedentary lifestyles; increased obesity
Explain how the action of hormones is specific
Each foreman has a function not carried out by any others; affects only the receptors on its target organ
Describe the role of the pancreas in the regulation of blood glucose
Produces insulin, which causes excess blood glucose to be stored; produces glucagon which causes release of glucose from store
Describe the role of the liver in the regulation of blood glucose
Stores excess glucose as glycogen; releases glucose from glycogen
Describe the control of blood glucose concentration in humans
Raised glucose triggers insulin release by pancreas; insulin causes liver to convert glucose to glycogen and store it; when glucose levels fall Glucagon released by pancreas; glucagon converts glycogen to glucose
Describe the two types of diabetes
Type one appears in childhood; cause by lack of insulin; Type II often appears in overweight individuals; caused by liver receptors not responding to insulin
Give the term used to describe the differences that exist between organisms of the same species
Variation
Give the meaning of the following terms haploid, diploid
Haploid is one set of chromosomes in the nucleus diploid is two sets of chromosomes in the nucleus.
Name the sites of gamete production and plants
Mail – anthers, female – ovaries
Name the male and female gametes in plants
Male – pollen, female – ovules
Name the sites of gamete production in animals
Male – testes, female – ovaries
Name of the male and female gametes and animal
Male – sperm, female – ova
Describe the process of fertilisation
Fusion of male and female gamete nuclei
Explain why body cells are diploid and gametes are haploid
Gametes haploid so the fertilisation restores the diploid state
Give the term used for a fertilised egg
Zygote
Now in the process by which diploid cells are maintained as an organism grows
Mitosis
Describe the differences between a sperm cell and ovum.
Sperm cells are tiny and have a tail for swimming; ova are large and have a food supply to feed the early embryo
Describe how fertilisation is achieved in a flowering plant
Male pollen carried from anthers by wind or insects; pollen arrives on female parts of flower; pollen grows through female tissue to reach the ovary; pollen nucleus fuses with female ovule nucleus
Give the term used to describe the differences that exist between organisms of the same species
Variation
State what is meant by the following terms: continuous variation, discrete variation
Continuous variation is variation that shows a range of differences. Discrete variation it’s variation in which the values are clear-cut
Give an example of a characteristic in humans that shows continuous variation
Height, weight
Give an example of a characteristic in humans that shows discrete variation
Blood-group, eye colour
State what is meant by the term polygenic
Controlled by the activity of a group of genes
In the human cystic fibrosis examplewhat is the chance that a child of two heterozygous parents would inherit the condition
One chance and four or 25% chance
Describe the difference between the terms gene and allele
Gene codes for a characteristic; allele is a form of a gene
Describe the difference between the terms genotype and Phenotype
Genotype - statement of alleles of individual; phenotype- outward appearance of individual
Describe the difference between the terms homozygous and heterozygous
Homozygous, having two alleles the same; heterozygous, having two different alleles
Describe the difference between the two dominant and recessive
Dominant alleles always show in the phenotype; recessive alleles only show in the phenotype type when homozygous
Describe the importance of variation to a species
Variation is differences between members of the species; variation is messaging attic and can be inherited; natural selection axon variation; result of natural selection is evolution
Give two reasons why plants need a transport system
To transport water to leaves for photosynthesis; transport food around the plant
Give two examples of substances that need to be transported around a plant
Sugar, water, minerals
Give the structure of the xylem vessel
Narrow, hollow, tube shaped; walls of lignin
State the part played by xylem vessels in plant transport
Conduct water up from roots towards stems and leaves
Name the process by which water vapour evaporates through the stomata of leaves
Transpiration
State the role of the guard cells in the epidermis of a leaf
Can change shape to open and close the stomata, so controlling gas exchange
State the role of the phloem tubes in the transport system of a plant
Transport sugars around the plants
Give three reasons why plants require water
Photosynthesis; transport of substances; support for plant; cooling affect of transpiration
Describe the uptake of water by plant roots and the role of the root hair cells in the root epidermis in this process
Water uptake by osmosis; root hair cells increase the surface area of root epidermis
Describe the role of the spongy mesophyll and pulling water through the xylem vessels
Do uses water by evaporation to leave airspaces; lowers water concentration in Mesophyll cells; allows water to be drawn into Mesophyll from xylem by osmosis
Describe the uptake and movement of water through a plant
What are taken into groups by osmosis water passes up the silence any: what are drawn into leaf by osmosis; water evaporates into airspaces in leave; water moves out of leaf to air through stomata
State the function of the heart
Pumps blood around the body
Name the four chambers of the heart
Right and left atria, right and left ventricles
Name the following blood vessels: vein that pretends deoxygenated blood from the body to the heart. Artery that transports deoxygenated blood from the heart to the lungs. Vein that transports oxygenated blood from the lungs to the heart. Artery that transports oxygenated blood from the heart to the body
Vena cava, pulmonary artery, pulmonary vein, aorta
State the general role of valves
Prevent back flow of blood
Name the artery supplies the cardiac muscle of the heart with blood
Coronary artery
Name the following blood vessels: supplies the liver with blood from the heart, artery that supplies the kidney with blood from the heart, vein that transports blood from the small intestines to the liver
Hepatic artery, renal artery, hepatic portal vein
Name the red coloured substance in blood and state its function
Haemoglobin and it carries oxygen
Explain the differences between the muscular wall of the left ventricle and the wall of the right ventricle
Left ventricle has a thicker muscular walls on the right; left has to pump blood around the whole body and right ventricle only pumps blood to the lungs
Describe the general functions of the following blood vessel types: arteries, veins, capillaries
Arteries carry blood from the heart to the organs, veins return blood to the heart from the organs, capillaries exchange substances with tissues
Explain how the structure of red blood cells helps them carry out their function
Red blood cells have no nucleus which gives extra space inside; they are very small with dimples on each side, which increases the surface area for gas exchange; they contain haemoglobin, which carries oxygen
State the function of the rings of cartilage around the main airways
Keep airways open
Give three features of alveoli that allow efficient gas exchange
Large surface area good blood supply thin walls
Name the fingerlike projections that line the inside of the small intestines
Villi
State how glucose and amino acid’s are absorbed by the villi
Taken directly into blood in capillaries
State how the products of fat digestions are absorbed by the villi
Taken directly in to the lacteal
State how glucose and amino acid’s are transported around the body
Carried in the blood stream
State how The products of fat digestion are transported around the body
Carried in the lymphatic system
Describe the role of the mucus and cilia in the main airways
Mucus traps particles; cilia beat and sweep mucus up and out of the breathing system
Describe the action of peristalsis
Circular muscles relax in front of food; circular muscles contract behind the food and push it along
Describe the similarities in the structure and function of the alveoli and the villi
Both have a large surface areas; thin walls; moist walls; good blood supply
Give three examples of lifestyle choices that can result in health problems
High-fat/salt/sugar diet, insufficient exercise, smoking, excessive alcohol intake
State what is meant by the term obesity
Hi levels of body fat relate to excessive food intake
State what is meant by the phrase high blood pressure
Blood forced excessively against walls of blood vessels
Give two examples of how stress can lead indirectly to health problems
Can lead to over eating or eating unhealthy food/smoking/drinking alcohol; can lead to heart-attack///high blood pressure/diabetes
Describe health problems that can be linked with any three of the following lifestyle choices: high saturated fat and diet, high salt in the diet, lack of exercise, use of tobacco, abuse of alcohol
Obesity,high cholesterol levels Raised blood pressure Obesity,artery blockage diabetes Heart disease cancers Liver disease
