Grade 12 Bio Exam Flashcards
1
Q
What is pollination?
A
Transfer of pollen (male gametes) from a male reproductive organ to a female reproductive organ in a plant
2
Q
What is fertilization?
A
The male and female gamete unite to form a zygote
3
Q
Define : homozygous
A
2 alleles for a trait are the same
4
Q
Define: heterozygous
A
2 alleles for a trait that are not the same
5
Q
What kind of plants did Mendel use in his experiments ?
A
Pea plants
6
Q
What was the process called that Mendel used when he wanted to breed one plant with another?
A
Cross pollination
7
Q
DNA is composed of small units called _______?
A
Nucleotides
8
Q
Define: double helix
A
Two spirals wound around each other
9
Q
Define: genes
A
Stretch of DNA that codes for a trait
10
Q
What is complementary DNA ?
A
Bases on one strand match up with the bases on the other strand ( A-T and C-G)
11
Q
What is DNA replication?
A
Process by which DNA copies itself
12
Q
DNA never leaves the ____?
A
Nucleus
13
Q
What is RNA?
A
A copy of DNA that goes out into the cytoplasm to tell the cell what to do in order to stay alive
14
Q
How does mRNA tell the cell what to do?
A
- mRNA is a message that codes for protein
- proteins are made in the cytoplasm and then work to keep the cell alive
15
Q
What is a mutation?
A
A change in the DNA sequence
16
Q
What is frame shift mutations?
A
Bases are inserted or deleted
17
Q
What are chromosomal mutations?
A
Chromosomes break or are lost during mitosis or meiosis
18
Q
Describe the nucleus:
A
- command centre
- most cells have a nucleus
- contain thins fibres called chromatin and coil to become compact chromosomes
- covered in a double nuclear layers with pores that allow passage of certain materials
19
Q
What is nucleolus?
A
- found inside the nucleus
- cells may have one or two nucleoli
- contains RNA granules that assemble ribosomes to make proteins
20
Q
What are chromosomes?
A
Long strands of DNA found in the nucleus
21
Q
What is a chromatid?
A
Single strand of DNA
22
Q
What is an anticodon?
A
A sequence of nucleotides on the opposite side of the tRNA molecules from the amino acid attachment site, that is the complement of the nucleotides in the codon
23
Q
How are amino acids joined together?
A
Peptide bonds
24
Q
What is the function of the stop codon?
A
It stops transcription
25
Where does translation occur?
In the ribosome in the cytoplasm
26
What is the role of ribosomes in protein production?
They travel along strands of mRNA and provide sites for tRNA to attach according to the codon sequence
27
Transcription :
- where is the process located?
- is DNA directly involved in this process?
- which types of RNA are involved ?
- nucleus
- yes, because it occurs in the nucleus
- mRNA only
28
Translation:
- where is this process located?
- is DNA directly involved in this process?
- what types of RNA are involved?
- end result
- in a ribosome outside of the nucleus
- No, because DNA is located in the nucleus
- tRNA
- chain of amino acids
29
What is a difference between RNA and DNA?
RNA contains uracil and DNA contains thymine
30
How many bases code for the amino acids ?
3 wash
31
Where are codons found?
mRNA
32
What is a plasmid?
A small ring of DNA found in a bacterial cell
33
What is a vector?
Carrier used to transfer a foreign DNA fragment into a host cell
34
What are restriction enzymes?
Bacterial proteins that have the ability to cut both strands of the DNA molecule at certain points
35
What happens is the result of gene splicing?
Allowed foreign protein to be expressed
36
What is the role of bacterial proteins in DNA cleavage?
To attach their partner (a-t and c-g)
37
How are restriction enzymes important in genetic engineering?
The enzymes are used by bacteria to shred invading viruses
38
What is a linkage map?
Shows the location of genes on a chromosome
39
How do scientists use relative dating to determine the ages of rock or fossils?
Utilizing the radio active decay in rocks
40
Describe the characteristics of the first organisms on earth:
- prokaryotic
- anaerobic
- heterotrophs
41
Who developed the theory of natural selection?
Charles Darwin
42
What is adaptive radiation ?
When an ancestral species evolves it can array of species to fit a number of diverse habitats
43
What is artificial selection?
A technique in which the breeder elects particular traits
44
What is the role of mimicry?
Protects an organism by copying the appearance of another species
45
Define: gene pool
Total number of genes present in a population
46
What is adaptive radiation?
The evolution of an ancestral species into an array of species that occupy different niches
47
What is a pedigree chart?
Diagram that shows how one trait is passed on
48
What is a multiple allele?
More that two alleles exist for a trait
49
What are some genetic disorders?
Sickle anemia
50
Describe the structure of a virus:
- a nucleic acid core
| - a protein over coat called a capsid
51
What are monerans?
Smallest living things
52
Describe a moneran:
Unicellular, microscopic, no nucleus, prokaryotic
53
Define: saprophytic
Feed on dead substances
54
Define: parasitic
Obtain nutrients from living organisms
55
What is a receptor site?
Where a virus attaches to a host cell
56
Define : host
A cell in which A virus replicates
57
Where is the genetic material of a bacterium found?
Flagellum
58
What is a bacteriophage?
A virus that infects a bacterium
59
Define : bacterium
Genes located in a single circular chromosome
60
Describe two ways that bacteria reproduce:
Binary fission- reproduce asexually, produces exact replica of itself
Conjunction- sexual reproduction, produces a bacterium with a new genetic composition
61
Define: provirus
Viral DNA inter grated into the host cell's chromosome
62
Define: retrovirus
Virus makes DNS from host cell's RNA
63
What are some advantages of using scientific names for organisms ?
- they are Latin names so they will never change
- names according to characteristics
- can distinguish between the first word and second word
64
What are some characteristics of fungi?
- do not photosynthesize
- do not have roots or stems
- do not contain cellulose on their cell walls
- obtain nutrients by absorbing nutrients from organic material
65
What are basidia and where are they found?
They are basidiomycetes which produce spores. They are found on gills of mushrooms under the mushroom cap
66
Define : deuteromycetes
Make up a division of fungi that have no known sexual stage
67
What is hypha?
Basic structure of multi cellular fungi
68
Compare and contrast basidium and basidiospores:
Basidiospores are produced in the basidium during reproduction
69
Through what structure is waste removed from a paramecium?
Anal pore
70
Compare and contrast microncleus and macro nucleus :
Macro- metabolic functions and rest of cell
| Micro- reproductive/ heredity functions
71
How does water leave and enter the paramecium?
Contractile vacuole pumps it out
72
What is the primary food of paramecium and how is it ingested?
Other smaller protozoans , through the mouth bacteria
73
Describe the digestion of food in a paramecium:
Digested with enzymes in the food vacuole into oral groove and gullet, makes food vacuole, enzymes digest it and nutrients diffuse into the cytoplasm
74
Define fragmentation:
A kind of reproduction that occurs when an individual breaks up into pieces, each of which grows into another individual
75
Define: pseudopodia
Extension of an amoebas plasma membrane, which function in locomotion
76
Why do euglenoids have characteristics of both autotrophs and heterotrophs ?
Because they are able to photosynthesize but when sunlight isn't available, they are able to absorb nutrients across their cell membrane
77
What are gametes?
Make and female sex cells
78
What are some characteristics of sponges?
- multicellular
- all aquatic
- body with pores, canals and chambers
- filter feeders
78
What are the 2 ways of reproduction ?
Asexual by budding and sexual by fusion of games
78
Characteristics of roundworms?
- tube within a tube body plan
- 2 openings , mouth and anus
- free living in soil
79
What are 3 ways in which roundworms differ from flatworms ?
- have a mouth and an anus
– well developed sense organs
- tube like digestive system
80
What are tunicates?
Marine animals
81
What is meant by animal behaviour?
Anything an animal does in response to a stimulus
82
What is learned behaviour?
When behaviour changes through practice or experience
83
What are some characteristics on monocots?
Parallel Venetian in leaves
- flower parts in multiples of 3
- vascular system scattered in cross section of stems
84
Characteristics of dicots:
- net venation in leaves
- flower parts in multiples of 4 or 5
- vascular tissues in rings in cross section of plants
85
What are gymnosperms? And some examples
Diverse group in which the seeds are exposed
| - conifers, cycads, ginkgoes
86
What are angiosperms? And some examples
Flowering plants and their seeds are enclosed within fruits
| - dicots and monocots
87
What are vascular tissues?
Made up of tubelike, elongated cells that food and other materials are transported through
88
What are some examples that influence population growth?
- Natality
- mortality
- immigration
- emigration
89
Describe the feeding process of a sea star:
Pushes stomach out and spreads it over the food, powerful enzymes secrete and turn food into liquid that can be absorbed the IT pulls its stomach back inside
90
What is translation?
Process of mRNA moving from the nucleus into the cytoplasm that goes to the ribosomes where the mRNA get decoded by tRNA
91
2 main groups of amphibians:
Anura- frogs and Todd ( legs no tail)
| Caudata- salamanders ( have a tail and legs )
92
What is the theory of natural selection ?
Individuals variations are likely to survive and reproduce because they can adapt
93
What are some spore dispersing plants?
Whisk ferns, club mosses , horse tails and ferns
94
What are some types of fungus?
Ascomycetes
Basidiomycetes
Zygomycetes
Deuteromycetes
