Eukaryotes, Prokaryotes & Evolution (2) + (4) Flashcards

Question

*Say yes or no for each of the following characteristics for:* **ANIMALIA** 1. DNA in the cytoplasm 2. No organelles 3. Unicellular 4. Multicellular 5. No cell wall 6. Cell wall made from... 7. Photosynthetic 8. Chloroplasts 9. Heterotrophic 10. Saprotrophic 11. Chemoautotrophic 12. Nervous system 13. Hyphae

Answer 1

1. No 2. No 3. No 4. Yes 5. Yes 6. NO 7. No 8. No 9. Yes 10. No 11. No 12. Yes 13. No

Answer 2

*Charles Darwin* travelled to the Galapagos in 1831-36. He studied finches on different islands- they had different size + shapes of beaks. These were *selected for* by the *food sources available* on each island. **ADAPTIVE RADIATION/ DIVERGENT EVOLUTION**. from one common ancestor species. **Homologies: same structure** in **different species** modified for different uses. Unfit species are constantly replaced by fitter ones, explaining extinction and unknown animals in the fossil record. *Alfred Wallace* studied invertebrates in Papua New Guinea. He found that related species inhabit neighbouring areas. Isolating barriers prevent hybridisation of species and further drive evolution.

Answer 3

EUKARYOTIC cells contain membrane-bound organelles PROKARYOTIC cells do not contain membrane-bound organelles or a nucleus. EUKARYOTIC cells' genetic information is contained in the membrane-bound nucleus. EUKARYOTIC cells have linear DNA. PROKARYOTIC cells have a smaller, circular genome, not contained in a nucleus but in the cytoplasm. The nucleoid is where the DNA exists, there is a smaller quantity of DNA.

Answer 4

1. cytoplasm (contains DNA) 2. cell membrane 3. mesosome 4. cell wall 5. capsule 6. small ribosomes (compared to eu cells) 7. plasmid 8. *(flagella)* 9. *(pili)*

Answer 5

* the site of PROTEIN SYNTHESIS; it is rough due to the ribosomes on its surface* * it is a network of folded membranes from the outer membrane of the nucleus, forming LAMELLAE/CISTERNAE*

Answer 6

1. Yes 2. Yes 3. Yes 4. No 5. No 6. PEPTIDOGLYCANS 7. Yes 8. No 9. Yes 10. Yes 11. Yes 12. No 13. No

Answer 7

1st stage: **LIGHT DEPENDENT reactions,** **occur on the THYLAKOID MEMBRANES** light energy is converted to chemical energy 2nd stage: **LIGHT INDEPENDENT reactions, occur in STROMA** carbon dioxide is fixed into organic compounds

Answer 8

1. chloroplast 2. large central vacuole 3. starch granules 4. cell wall

Answer 9

An organism that can live at **extremes** of **temperature, pH and salinity.** *A classificatory group.*

Answer 10

ACTIN (protein) gives the cell **strength**, **support** and keep the cell's **shape** allow cell movement eg. changing the shape of the cell; endo/exo-cytosis

Answer 11

*A population has some naturally-occurring genetic variation.* A **change in the** **habitat** causes a **change in the selection** acting on the population ; an **allele** that was of no particular advantage before now becomes **advantageous**. Organisms with the allele are **more likely to survive**, **reproduce** and so **produce offspring** ; their offspring have the advantageous allele, so it becomes **more frequent** in the population.

Answer 12

1. It is EXTERIOR to the cell. 2. made of CELLULOSE, secreted by the GOLGI APPARATUS of cell.

Answer 13

An organism that obtains its **energy and nutrition** from **organic matter.** A SAPROTROPH is a type of heterotroph: *an organism that obtains its **energy and nutrition** from **dead and decaying matter** which has **been digested** **extra-cellularly**, by **secreting** extra-cellular **enzymes** which break down the matter outside the organism into **soluble** material which is then **absorbed**.*

Answer 14

**Cell wall is not made of peptidoglycan** (Bacteria cell wall is) **Histone proteins in combination with DNA** (Bacteria DNA not coiled, free-floating in cytoplasm) **Several types of RNA polymerase** (bacteria= one type) **Insensitive to streptomycin antibiotic** (Bacteria are sensitive)

Answer 15

*Respiratory pigment present in the animal kingdom.* Species **more closely related** have more **similar primary structure/sequence of amino acids in haemoglobin**. **Phylogeny** based on this evidence shows that species in the same same genus have a more recent common ancestor that species in the same phylum.

Answer 16

*the site of aerobic respiration* frequent in metabolically active cells eg. liver, muscle, neurones, spermatozoa

Answer 17

* To see the similarities between sequences of proteins and/or genes found widely in different species eg. **cytochrome C** (from ETC)* * and **haemoglobin***

Answer 18

C₆H₁₂O₆ + 6O₂ ----------\> 6CO₂ + 6H₂O * glycolysis* * Krebs cycle and Link reaction* * electron transport chain (ox. phos.)*

Answer 19

**EU usually larger cells 10-100um diameter** *PRO usually v small 0.5-10um diameter* **EU cell division preceded by mitosis, meiosis** *PRO cell division preceded by DNA replication* **EU nucleus present, nuclear envelope double membrane perforated by pores, DNA in linear chromosomes and combined with histone proteins** **EU reproduction; gametes/sex cells with equal contribution from both nuclei** **EU cell walls present in plants, fungi, photosynthetic protoctista, do not contain peptidoglycans + mucopeptides** **EU many organelles, some bound by double membranes - mitochondria, chloroplast, nucleus** **some bound by single membranes** **EU protein synthesised in 80S ribosomes** **EU some have cilia, flagella, which is larger 200nm diameter** *PRO some have flagella, pili, which are*

Answer 20

**nuclear envelope** *DOUBLE MEMBRANE surrounding nucleus* **nuclear pores** site of steroid hormone, nucleotide REGULATES PROTEIN ENTRY, mRNA EXIT **nucleolus** site of TRANSCRIPTION RIBOSOME FORMATION (rRNA synthesis) **chromatin** 2 types: euchromatin and heterochromatin

Answer 21

Using different **types of molecules** to see the **extent** of the **similarities** between them in **different species**, to study their **evolutionary relationship/history**. ***Antibodies, Protein & DNA sequencing, DNA hybridisation***

Answer 22

It is made of **intercellular proteins**: microfilaments, intermediate filaments and microtubules. It provides **strength, shape, support and movement** within the cell.

Answer 23

a boundary between the cell and its environment/extracellular fluid SELECTIVELY PERMEABLE: only certain material is capable of passing through/permeating it; IT CONTROLS AND REGULATES EVERYTHING THAT ENTERS OR LEAVES THE CELL * is a functional structure* * its surface area is increased by microvilli* * in unicellular organisms eg. amoeba, it allows movement and nutrition*

Answer 24

*Mainly multicellular, but some are also multicellular* 2 Subkingdoms: ALGAE PROTOZOA there is a third group between the two that have chloroplasts but no cell wall eg. EUGLENA

Answer 25

* Pesticide bountifully applied by humans to crops * Most insects die, but a couple have **random mutation**s that lead to an **allele conferring resistance to pesticide**. * The survivors have **no competition for resources** because those without the advantageous allele are killed by the pesticide. Therefore the **survivors grow in number more rapidly**. * Additional applications will be **less effective** + the **frequency** of resistant insects in the population **increases**.

Answer 26

**cytosol/cytoplasm** **cell surface membrane** **nucleus** **endoplasmic reticulum** **golgi apparatus** **lysosomes** **mitochondria** **cytoskeleton**

Answer 27

**Mutations are random & already exist in the population.** This leads to variation in the susceptibility of bacteria in the population to antibiotics. Widespread use of antibiotics is the selection pressure for bacteria. The non-resistant bacteria will die. If the course of antibiotics is not finished or the amount of antibiotic is too low, the more resistant individuals will survive. For the survivors there is very little competition for food etc., therefore they divide quickly and produce a highly resistant population. It can exchange genetic material with other bacteria (horizontal gene transmission). The antibiotic is now ineffective.

Answer 28

* **DNA** is cut into **small sections** * **Heating** the DNA molecules to **break the H-bonds** and **separate** the two strands of the double helix * **Mixing the single-stranded DNA between species** to see the **extent of hybridisation**; the more similar the base sequences are, the better the strands bond and form a double helix, the closer the species are.

Answer 29

A **group of organisms** that can interbreed to produce **fertile offspring.** Binomial nomenclature: scientific name of 2 parts eg. *_Homo sapiens_*

Answer 30

The original classification of taxonomical groups KPCOFGS used **anatomical** and **physiological** (visible) similarities and differences. In the late 20th century, the domains were introduced to give greater significance to similarities and differences in **molecular biology, i.e. cellular and biochemical**. *3 domains: _EUKARYOTAE_* all kingdoms except prokaryotae *_ARCHAEBACTERIA_* extremophile bacteria *_EUBACTERIA_* all other bacteria

Answer 31

**INTRAspecific variation** *variation between individuals of the same species* the greater the **genetic diversity** of a species, the greater the **intraspecific** variation. Genetic diversity in species is due to meiosis and sexual reproduction ( and random mutation leading to new alleles).

Answer 32

1. Needs an **environmental condition** which causes a **pressure** ( called a *selection pressure*/natural selection eg. disease) 2. Needs the **offspring to look like them** i.e. because the alleles are inherited) 3. These offspring must **survive and reproduce** 4. There must be an **increase** in the **proportion** of the population **possessing the advantageous characteristic** (+ decrease in the proportion of the population that has the disadvantageous allele)

Answer 33

* Only **20 amino acids** are used to make **proteins**- the **same** 20 in all organisms. **Genetic code** specifying amino acids is the **same** in all organisms and **universal**. * Molecule of inheritance in all cellular organisms - **eu and pro**- is **DNA**. * **ATP** is the **universal currency** for **energy** in the cells of all organisms. *Analysis of **AAs of proteins** from closely related species are very similar eg. cytochrome C, haemoglobin.*

Answer 34

Making **evolutionary links** eg. *physiological or anatomical similarities*. Similarities are *shared features* that are *inherited* from a *common ancestor.* These lead to the natural classification system, which is based on similarities.

Answer 35

**Placing living organisms** into groups (**taxons**) according to **similarities + differences**. ## Footnote *(each successive group contains more and more different kinds of organisms- (D)KPCOFGS)*

Answer 36

**small gaps in cell wall** and the **middle lamellae** (made of pectin, point of contact between 2 cell walls) where the **cytoplasm of adjacent cells meet**

Answer 37

* site of photosynthesis* * found in the palisade mesophyll layer of the leaf*

Answer 38

a vesicle containing hydrolytic enzymes **lysozymes** which degrade waste/unwanted substances in the cell created by the golgi apparatus

Answer 39

* (Domain: Eukaryotae)* * Kingdom:* **Animalia** * Phylum:* **Chordata** * Class:* **Mammalia** * Order:* **Primates** * Family:* **Hominidae** * Genus:* **Homo** * Species:* **sapiens**

Answer 40

**N₂→ NH₃ → amino acids → protein → cytoplasm/membranes/enzymes** N₂ is fixed by the **nitrogenase** enzyme, energy from **ATP** + reducing power of H⁺ from resp. of glucose from _host plant_ NITROGENASE is inactivated by *oxygen* Ammonia is combined with _keto acids_ to form amino acids

Answer 41

thylakoid membranes, arranged into grana (granum, a stack of t. m.), connected by integranal lamellae, surrounded by stroma DNA, ribosomes, starch granules all surrounded by chloroplast envelope

Answer 42

capsule; **slimy layer surrounding cell wall** **IT ALLOWS CELL-CELL ADHESION + COLONY FORMATION** mesosome; **invaginations of the plasma membrane, INCREASED SURFACE AREA FOR REACTIONS eg. electron transport chain, site of enzymes and pigments** cell wall; **made of peptidoglycans and mucopeptides to avoid osmotic swell** plasmid DNA; **confers antibiotic resistance**

Answer 43

**_THE ANCESTRAL SPECIES NEEDS:_** 1. **Geological time**- evidence provided by *fossils*, supported by *DNA and molecular evidence* 2. **Variation** in the species- occurs by *random mutations*, most are detrimental but a few are *advantageous*- these give the individual a better chance of *survival.* TYPES: **continous + discontinuous.** CAUSES of VARIATION: **genetic + environmental** 1. **Large numbers** in the population/**overproduction** and **competition** for resources 2. Some individuals must be **better adapted** because of their **mutation**; these individuals must **survive and REPRODUCE**

Answer 44

cytosol + all organelles (except nucleus) site of many **chemical/metabolic** reactions surrounded by the cell surface m/plasma m

Answer 45

***Mineralised** or other **preserved remains** of **once living** organisms.* Fossils are formed from faeces, footprints, burrows etc. **Layers of sedimentary rock** can reveal the **age** of **fossils** i.e. the age of the **rock**. (**Radiocarbon dating** can be used on remains of 50,000 years ago or less). Fossils can be used to show where there are **links between extinct + extant organisms** eg. archaeopleryx, the link between birds and reptiles.

Answer 46

the **site of post-translational protein and lipid modification** (from RER and SER, respectively). they are **transported in vesicles** to intra or extracellular destinations ## Footnote some vesicles remain in the cell eg. lysosomes, peroxisomes. others exocytose eg. digestive enzymes, hormones *appearance- many vesicles at ends of lamellae, more curved than SER*

Answer 47

* **all multicellular** * **photosynthetic** * contain **chloroplasts**/chlorophyll * contain **cellulose cell wall** * **starch** is the storage carboydrate *Examples of PHYLA: Liverworts + mosses, Ferns, Conifers, Angiosperms*

Answer 48

CENTRIOLES for mitosis and cell division ## Footnote *make up the centrosomes (only in animal cell division) which duplicate and move to opposite poles of the cell before division*

Answer 49

an UNICELLULAR organism; ancestor of all living organisms (the origins of mitochondria + chloroplasts) NO NUCLEUS, NO MEMBRANE-BOUND ORGANELLES the DNA is contained in CYTOPLASM

Answer 50

1. No 2. No 3. Yes 4. Yes 5. No 6. CHITIN 7. No 8. No 9. Yes 10. Yes 11. No 12. No 13. Yes

Answer 51

* the organelle in which post-translational modifications are made to proteins* 1. ADDITION TO PROTEINS the addition of a carbohydrate chain to the protein, creating **glycoproteins**, or the addition of lipids to the protein, creating **glycolipids** 2. ADDITION OF PROSTHETIC GROUPS to proteins, such as haem (blood)

Answer 52

* to **overcome different common names** being used in different countries * to overcome names in **different parts of a country** * **translation** of languages or dialects may vary * the *same common name* may be used for **different** species

Answer 53

*MONERA - PROTISTA - PLANTAE - FUNGI - ANIMALIA* Bacteria, Archaea, Protista, Plantae, Fungi, Animalia

Answer 54

large structure, approx. 20nm, seen by an electron microscope, not LM made of PROTEINS and RIBOSOMAL RNA (rRNA) 80S in eukaryotic cells, 2 subunits 70S in prokaryotic cells, mitochondria of eus, chloroplast of eus *not surrounded by a membrane*

Answer 55

6H₂O + 6CO₂---------\> 2(C₃H₆O₃) + 6O₂

Answer 56

1. centrioles 2. flagella/cilia

Answer 57

1. No 2. No 3. No 4. Yes 5. No 6. CELLULOSE 7. Yes 8. Yes 9. No 10. No 11. No 12. No 13. No

Answer 58

the site of **lipid synthesis and carbohydrate synthesis** no ribosomes. - smooth appearance

Answer 59

1. No 2. No 3. Yes 4. Yes 5. No 6. CELLULOSE 7. Yes 8. Yes 9. Yes 10. No 11. No 12. No 13. No

Answer 60

They contain a **cell wall** made of **chitin** **Not photosynthetic** **Heterotrophic**, and mostly **saprotrophic** **Glycogen** is the main **storage** carbohydrate Mainly **multicellular** but may be **unicellular** eg. yeast Contain **thread-like projections ; hyphae.** They criss-cross into their food source to form **mycelium.**

Answer 61

- allow **movement of organelles** within the cells - form the **spindle in mitosis**, allowing movement of chromosomes to opposite poles of the dividing cell - make up **cilia, flagella, centrioles, undulipodia**

Eukaryotes, Prokaryotes & Evolution (2) + (4) Flashcards

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