Biology Module 4 Flashcards

Question

What is the order of classification?

Answer 1

Dumb King Phillip Came Over For Group Sex Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Answer 2

The study of evolutionary relationships between organisms, eg, putting animals in an evolutionary/phylogenic tree.

Answer 3

They are prokaryotic organisms that evolved from Eukarya after bacteria did. They are different from both for a number of reasons: 1. They have 3 RNA polymerase's to code for the 3 different types of RNA, whereas bacteria only has 1 2. Their cell walls do not contain peptidoglycan, unlike bacterial cell walls 3. They have cell membrane that contain lipids with hydrocarbon chains rather than fatty acids

Answer 4

It is needed to have a universal and internationally recognised naming system for species, stopping any confusion about species between languages. The way to write the name is to write the genus in a capital letter, the species in a lower-case letter, and in italics or under-lined.

Answer 5

A group of organisms that are very similar in appearance, anatomy, biochemistry, physiology and genetics, and can reproduce sexually to produce fertile offspring.

Answer 6

Convergent evolution is evolution that occurs in organisms that are not related, but are anatomically similar due to being subject to similar evolutionary pressures. Divergent evolution is evolution that results in organisms becoming more anatomically different, represented by a branch from the phylogenetic tree.

Answer 7

-Using a protein called Cytochrome C -This is useful as it a protein used in respiration -This means all eukaryotes have it -Therefore, the primary structure of cytochrome c can be compared across species, using a matrix, to place them on a phylogenetic tree relative to others

Answer 8

1. Artificial classification 2. Natural classification

Answer 9

Grouping organisms based upon like characteristics, eg, organisms that are orange. Advantages: -Does not changed based upon further knowledge, ie, both organisms will still be orange -Convenient Disadvantages: -Not useful to find the species evolutionary history -Provides limited information, ie, organisms are orange

Answer 10

A detailed study on an organisms many characteristics, eg, genetic, anatomical and molecular evidence. Advantages: -Many different characteristics used -Reflects phylogenetic relationships between species -Provides information on evolutionary history Disadvantages: -May change with further knowledge

Answer 11

Inter-specific: -The variation found between species Intra-specific: -The variation found between organisms in a species Discontinuous: -Variation caused by solely genetic factors Continuous: -Variation caused by both environmental and genetic factors

Answer 12

Discontinuous: Data that can be separated into distinct groups, with no middle values, like nominal data, eg, shoe size being 7, 7.5 and 8, not 7.3 Continuous: Data that could be any data value in a range, so there is no distinct separation, like ordinal or interval data, eg, height in cm

Answer 13

Independent sample t-test is a test used to investigate the differences between 2 samples (independent measures design) Paired sample t-test is a test used to investigate differences over time, using the same sample (repeated measures design)

Answer 14

A large number of genes that work as a group to control or have an effect on one continuous characteristic.

Answer 15

-An adaptation is any variation that helps an organism to survive in its habitat -The 3 types are behavioural, physical and physiological -Behavioural - a variation in how an animal behaves, and certain reflexes -Physical - a change in the physical structure of an organism or cell, eg, bipedalism -Physiological - a variation in the chemical processes of an organism, eg, the ability to anaerobically respire

Answer 16

A disorder of the mind or body that causes poor health.

Answer 17

Pathogen: -An infectious microorganism that causes disease -4 main types: viruses, bacteria, fungi and protists Parasite: -An organism that survives in or on another species, usually surviving at their hosts expense

Answer 18

-Prokaryotic organisms -They reproduce rapidly via binary fission, bursting out of cells, causing damage, and releasing toxins/waste into the bloodstream, inhibiting enzymes or processes -Some bacteria are non-pathogenic

Answer 19

TB /Tuberculosis (animal): -When infected organisms with the active form of the bacterium cough or sneeze, the bacteria enter the air via tiny droplets of liquid -Transmitted to uninfected individuals inhale these droplets, so TB spread much faster in overcrowded and unhygienic conditions -TB can occur in cows and spread to humans via unpasteurised milk and contaminated meat -Symptoms include a chronic cough and bloody mucus Ring Rot/Rot (plant): -Bacterial disease in potato plants -Bacteria infect vascular tissue and prevent transpiration, even in tubers, where vascular tissue is in a ring, causing typical black ring of rot, and eventual wilting and death

Answer 20

-Eukaryotic organisms that are usually spread via vectors -Divide via mitotic division/reproduce sexually -They can cause damage as they inhabit cells, ingesting the cell inside, use the cytoplasm as a reproductive medium and burst out of the cell, causing pain Malaria: -A protist disease transmitted when a protoctista passes from a vector to a human -Symptoms include fever, chills, fatigue and eventual death Potato/Tomato Blight: -Protist disease with fungal characteristics, as transmitted via spores -First signs are an increasing number and size of brown marks on leaves -Destroys crops leaving them inedible

Answer 21

-Female mosquito's fed on human blood to obtain the proteins to develop eggs -If the mosquito bites an infected individual and then an uninfected individual, the plasmodium will pass from one to the other 1.Infected mosquito feeds on an uninfected human 2.Ineffective parasites enter the bloodstream and then the liver 3.Leave the liver and enter erythrocytes 4.Parasites gametes mature and are produced 5.Mosquito takes blood meal and gametes fuse in mosquito's stomach 6.Division occurs and produces many inactive plasmodium's which enter mosquito salivary glands 7.Process occurs again -Due to global warming, more area are becoming habitable to mosquito's, so more cases are occurring -Increased migration and globalisation will also mean more mosquito's will become vectors around the world

Answer 22

-Not alive, a strand of mRNA surrounded by a protein shell -Reproduce by taking over cell's metabolism and producing more viruses via translation -This reproduction can cause cells to burst, spreading the virus

Answer 23

HIV/Human Retro-Virus (animal): -A retrovirus, a virus that can form DNA from RNA, transmitted via a vector -The virus is not able to survive outside the hosts body, and is spread through intimate human contact and the direct exchange of bodily fluids -The viral enzyme reverse transcriptase produces DNA from RNA -DNA is inserted into the hosts DNA and remains inactive for years until it is activated and the DNA provirus produces more viruses Influenza (animal): -3 different types, A, B and C -Infect the cells lining airways causing high temps, aches and fatigue -A is most common, consisting of a proteins shell (capsid) with 8 RNA strands inside it TMV/Tobacco Mosaic Virus (plants): -1st virus ever discovered -Occurs in a number of species, causing distinct mottled discolouring of leaves

Answer 24

-Eukaryotic organisms -Reproduce via spores -Can cause the area infected to become uncomfortable, swell or become painful -They feed on living matter, ingesting nutrients and carbs from the host organism Athletes: -Fungal disease existing on the surface of animals skin -Less serious infection than fungal infections in plants Black Sigatoka: -Fungal disease in bananas, spreading through plant leaves, inhibiting photosynthesis -Produces black streaks and causes plant leaves to die

Answer 25

Transmission is the process of passing a pathogen from an infected organism to a healthy one. 1.Direct Transmission - transmission of a pathogen via direct contact between a healthy and an infected individual, eg, bodily fluids 2.Indirect Transmission - transmission of a pathogen via other mediums such as the air, water, or other objects in the direct environment 3.Vectors - an organism or intermediary that carries a pathogen from one host to another

Answer 26

1.Direct contact refers to transmission via direct physical contact between individuals 2.Faecal-oral refers to transmission via direct contact between the mouth and faecal matter, through a number of mediums, eg, water 3.Droplet refers to transmission via tiny water droplets in the air, from the mouth of an infected organism 4.Spores refers to transmission via small reproductive structures in an environment, which, when in a host, grow and cause infection, eg, potato blight spores and wind

Answer 27

-Overcrowding -Poor nutrition -Compromised immune system -Culture -Socioeconomic status -Waste disposal -Vector distribution

Answer 28

Cellulose cell wall: -Acts as first barrier to invasion, and though not completely impregnable, has a high density stopping many pathogens Waxy cuticle: -Acts as a physical barrier, limiting direct contact between pathogens and the epidermis, and preventing H20 collection on leaves and so spore germination Bark: -Tough physical barrier blocking pathogens and containing anti-microbial chemicals, inhibiting micro-organism growth Lignin thickening: -Located in secondary cell walls, eg, xylem -Makes cell walls rigid and impregnable and hydrophobic nature stops the transmission of water-borne pathogens

Answer 29

Stomatal closure: -Stomata can close when pathogen-associated molecular patterns (pamps) are detected -Reduced chance of infection via stomata Tylose formation: -Causes swelling of parenchyma around xylem -Blocks xylem, preventing transpiration and places anti-microbial compounds into xylem Callose Deposition: -A polysaccharide, made of β-glucose, deposited between the plasma membrane and the cell wall -Forms barriers around plasmodesmata and sieve tubes, blocking movement between cells and deposited very quickly when a pathogen is detected 1.Callose deposited when a pathogen is detected, preventing further spread 2.Lignin added to callose to strengthen the barrier 3.Blocks sieve plates, preventing spread via the phloem 4.Blocks plasmodesmata between infected and healthy cells

Answer 30

Phytoalexin: -A chemical that is released when the breakdown of cellulose is detected, stopping pathogenic invasion from the surface of the plant -Can disrupt the metabolism, reproduction, cell surface membrane of bacteria, or release chitinase enzymes Alkaloids: -A group of nitrogen containing compounds that have physiological effects on pathogens -Often poisonous to pathogens and herbivores, often aa derivatives, eg, caffeine, cocaine and morphine Tannins: -Phenolic (containing benzene) compounds found in root cell vacuoles and cell walls -It is toxic to pathogens and herbivores, preventing infection Saponins: -Chemicals that kill pathogens via destroying cell membranes -This halts the growth and reproduction of pathogens Defensins: -Cysteine kills pathogens via channel protein inhibition, stopping many metabolic reactions within the pathogens, stopping the infection from spreading Hydrolytic Enzymes: -Enzymes that breakdown the cell wall of pathogens, and inhibits pathogenic reproduction VOC (Volatile Organic Compounds) : -Organic compounds that emit chemical signals that either directly repel or attract organisms to help with the defence against pathogens, eg, causing other plants to activate their defences

Answer 31

Skin: -Passive defence, with its outer layer consisting of a layer of dead cells impregnated with keratin -This means it is impenetrable to pathogens -Also secretes sebum, an anti-microbial compound that kills pathogens before it can cause infections Nose and Gaseous Exchange system: -Both lined with cilia, bathed in mucus, which is then swept towards the throat to be destroyed in the stomach -Pathogens and dust get caught in viscous mucus -Alveoli covered in mucus membrane containing lysozymes Stomach and Vagina: -Stomach produces HCl with pH ~2-2.5 -Vagina not as acidic at ~4-4.5 -Kills pathogens before they can reproduce Clotting: -Forms a barrier to the wound, acting as a physical barrier and stopping pathogen invasion through the bloodstream

Answer 32

-Platelets, when exposed to the outer protein layer of the blood vessels release a clotting factor, eg, thromboplastin -Thromboplastin causes prothrombin and Ca^2+ to combine to form thrombin -Thrombin then causes fibrinogen to form fibrin -Fibrin forms a mesh with erythrocytes to create a protective layer above the wound, that dries to form a scab

Answer 33

-They are very small fragments of short-lived cells -They are produced continuously in the bone marrow

Answer 34

-Mast cells activated during skin rupture and so release histamines and cytokines Histamines: -They cause vasodilation (vessel dilation), promoting more blood flow to the area and causing heat and redness -This stops pathogens from reproducing due to high *C -Also increases permeability of vessels causing more plasma to leak out to form tissue fluid, leading to swelling and pain -Allows more phagocytes to access the infected area Cytokines: -Attracts phagocytes and leucocytes to the area to kill pathogens -Phagocytes travel to hypothalamus to cause it to reset and increase internal body temp and stop pathogenic reproduction

Answer 35

-Opsonins are proteins that attach to foreign antigens on the surface of pathogens, allowing phagocytic cells to denote a pathogen as foreign and destroy it -Opsonisation is an immune process that uses opsonins to tag foreign pathogens for elimination by phagocytes

Answer 36

Antigens are proteins extrinsic to the cell-surface membrane that identify a cell as native or foreign to an organism. The 2 different types are self-antigens and non-self-antigens: Self-antigens: Antigens from a native cell Non-self-antigens: Antigens from a foreign cell or toxin

Answer 37

-The 2 main types of phagocytes are neutrophils and macrophages Neutrophils: -They are white blood cells that have a multi-lobed nucleus -They are manufactured in the bone marrow, and they travel via the blood, and can be found in the tissue fluid and on epithelial surfaces -They are released in large numbers during infection as they are short-lived as they die after digesting a couple of pathogens Macrophages: -They are manufactured in the bone marrow, and are larger than neutrophils -They travel in the blood via monocytes, before settling in organs, eg, lymph-nodes, before developing into macrophages -Don't fully digest pathogens, becoming antigen-presenting cells

Answer 38

1.The phagocyte recognises the pathogen via the opsonins on the antigens 2.Receptors on the phagocyte bind to the pathogen antigens 3.The cell-surface membrane invaginates, trapping the pathogen in a phagosome (a vesicle surrounding a pathogen) 4.Lysosomes fuse with the phagosome inside the phagocytes cytoplasm to form a phagolysosome (a cytoplasmic body formed when lysosomes fuse with a phagosome) 5.The lysosomes release enzymes that digest the pathogen, eg, lysin and lysozymes 6.The harmless waster products are either reused by the cell, or ejected from the cell via exocytosis OR 7.The macrophage presents the pathogenic antigens on their cell-surface membrane from the partially digested pathogen

Answer 39

-Antigen presenting cells are cells that present foreign antigens to produce a specific immune response -These can be macrophages, invaded body cells or cancerous cells as a sign of cellular distress

Answer 40

-T-lymphocytes are white blood cells that cause a immune response by dividing and differentiating, and have a complementary receptor for a specific pathogenic antigen -They are produced in the bone marrow and travel via the blood to the thymus gland where they mature 1.The antigen-presenting cell displays the foreign antigen and presents it to a T-lymphocyte 2.If the T-lymphocyte has a complementary receptor, it will bind to the cells, causing it to become activated 3.It then divides by mitotic division with the clones differentiating into 4 different types of T-cells

Answer 41

T-memory cells: -Remain in the blood for a long time so they can respond to future pathogenic invasion, from the same pathogen -Retain a memory as they have a specific pathogenic antigen receptor -Can enable a rapid response to a repeated infection, so is a secondary response T-helper cells: -Secrete cytokines to stimulate: -T-killer cells to destroy pathogens -Phagocytes to undergo phagocytosis faster -Stimulate B-lymphocytes to divide and differentiate to become antibody producing plasma cells T-killer cells: -Kills cells that present specific non-self antigens -Kills via a chemical is produces called perforin, making holes in the plasma membrane of the pathogen T-Suppressor cells: -Close down immune system activity when pathogen destroyed

Answer 42

They are disorders where the immune system can no longer recognise self antigens, and so starts attacking native cells and tissues.

Answer 43

SD = √[∑(x-x̄)^2/(n-1) SD=Standard deviation ∑=Sum off x=The data value x̄=The mean of the data n=The number of data values (When calculating x-x̄, do it for every data value before adding them together)

Answer 44

-Antibodies are specialised glycoproteins called immunoglobulins -They are specific and bind to only 1 type of antigen, like the lock and key theory for enzymes -When they bind to an antigen, an antigen-antibody complex forms, stimulating digestion via phagocytosis, like opsonins -They consist of 2 heavy chains, in the middle of the proteins, that are arranged in a y shape, joined together via disulphide bridges -2 light chains are then attached to the upper lengths of the heavy chains via more disulphide bridges -The bottom portion is called the constant region, and the area with the light chains changes between antibody molecules and so is called the variable region -The antigen-binding area is found at the end of the variable region and is specific a type of non-self antigen -The centre of the antibody is called the hinge area, and has many disulphide bridges that allow the 2 variable regions to move

Answer 45

-Agglutination and Neutralisation Agglutination: -1 antibody binds to 2 pathogenic non-self antigens, causing them to clump together, and allowing pathogens to be more easily engulfed and digested Neutralisation: -The antibodies can act as an anti-toxin, binding to pathogens and toxins, making them harmless to the organism

Answer 46

-B-lymphocyte cells are white blood cells that are made and mature in the bone marrow, before spreading mainly through the lymph-nodes and spleen -As they mature they develop BCR's (B-cell receptors), antibodies that develop extrinsic to the B-cells plasma-membrane, with each being specific to 1 non-self antigen B-effector cells: -These cells divide to form plasma cell clones B-memory cells: -These act like T-memory cells and remain in the blood for a long time, providing a long immunological memory -It actions a more rapid secondary response to repeat infection Plasma cells: -These cells produce antibodies specific to an invading pathogen, living only for a few days, but producing ~2000 antibodies when it is active

Answer 47

-The humoral immune response is a response to pathogens found in the blood, mainly fungi and bacteria 1.When a B- effector cell binds to a pathogen that has a complimentary antigen to its antibody, it digests it, presenting the non-self antigens 2.The presenting B-effector binds to a T-helper cell with a complimentary receptor, which is called clonal selection 3.The interleukins produced by the T-helper cell activate the B cells to rapidly undergo mitotic division to differentiate into the 2 other B-cells, called clonal expansion 4.Clonal plasma cells produce complimentary antibodies to bind to pathogenic antigens, and causing agglutination or neutralisation, disabling them

Biology Module 4 Flashcards

Biodiversity and disease (71 cards)