biology

Question 1

what does DNA stand for and what is it’s structure

Answer 1

Deoxyribose nucleic acid

phosphate, deoxyribose sugar, base (thymine, adenine, guanine, cytosine)

Question 2

what are genes

Answer 2

section of dna arranged along the chromosomes
a unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

Question 3

what are autosomes

Answer 3

chromosomes that aren’t gametes or sex cells

Question 4

XY is ? XX is ?

Answer 4

xy= female

xx=male

Question 5

what is the diploid and haploid

Answer 5

Diploid describes a cell that contain two copies of each chromosome
Haploid describes a cell that contains a single set of chromosomes

Question 6

what is the genotype vs phenotype

Answer 6

genotype is the genetic makeup of an organism (Rr, rr) whereas phenotype is the physical characteristics of an organism. (red and white)

Question 7

what is an allele, dominant and recessive

Answer 7

Individuals receive two versions of each gene, known as alleles, from each parent. If the alleles of a gene are different, one allele will be expressed; it is the dominant gene. The effect of the other allele, called recessive, is masked. (Rr) big R= dominant

Question 8

Homozygous vs heterozygous

Answer 8

homo= has 2 of the same gene
heter= has two different

Question 9

number of chromosomes, autosomes, sex chromosomes

Answer 9

on sheet

Question 10

what are mutagens/mutations

Answer 10

mutagens are physical, chemical and biological agents that change the DNA of an organism and thus cause a mutation.
phys-radiation-gamma rays
chem-arsenic
bio-virus-hpv

Question 11

what is point mutation vs chromosome mutation

Answer 11

point mutation occurs when one base is substituted for another
chromosomal mutation occurs when the centromere fails to separate during meiosis causing there to be too many or too few chromosomes

Question 12

what is point mutation vs chromosome mutation

Answer 12

point mutation occurs when one base is substituted for another (substitution)
chromosomal mutation occurs when the centromere fails to separate during meiosis.- causing there to be too few or too many chromosomes.

Question 13

what is frameshift mutation

Answer 13

is a deletion or addition of a base- causing the triplet reading frame to shift along the DNA strand

Question 14

define species

Answer 14

a group of organisms able to produce fertile offspring with one another

Question 15

define evolution

Answer 15

a change in allele frequencies or gene pool over time

Question 16

5 fingers of evolution

Answer 16

1. population can shrink
2. non-random mating
3. mutations
4. gene flow
5. adaption

Question 17

artificial selection

Answer 17

a method whereby humans can alter the characteristics of a population over time, and breed particular organisms with desirable features.

Question 18

natural selection

Answer 18

the process which populations of living organisms adapt and change to their environments.

Question 19

variation
competition
survival
inheritance

Answer 19

natural selection could only act if there’s variation in population.

Question 20

speciation

Answer 20

process where one species splits into two or more separate species.

Question 21

steps to speciation

Answer 21

1. variation- must be variation in population
2. geographical barrier- isolation into separate populations
3. isolation-

Question 22

evidence for evolution

Answer 22

fossils, comparative anatomy, geographical distribution,.

Question 23

analogous structure vs homologous

Answer 23

homo- same structure but have different function (limbs of humans and whales)
anal- different structure same function (wings of bats and birds)