bio midterm

who is mendel? what did he discover?

the father of genetics. discovered genetics and punnet squares

what is a gene

genetic material that codes for a trait

how many chromosomes do humans have

46

what is heredity

passing of traits from parent to offspring

genotype

genetic makeup/genes

phenotype

physical appearance

homozygous

same alleles

heterozygous

different alleles

dominant

stronger gene, one that appears when the allele is present

recessive

weaker gene. one that is hidden by the dominant allele

allele

different versions of the same gene

codominant

occurs when both alleles for a gene are expressed in a heterozygous offspring

incomplete dominance

appearance that somewhat is in between the phenotypes of the 2 parental varieties

what is a dominant gene and what kind of letter would you use to represent it

the stronger gene. a capital letter represents it

what is a recessive gene and what kind of letter would you use to represent it

the weaker gene. a lowercase letter represents it

this trait is masked when the dominant allele is present

recessive

different forms of genes are called

alleles

he is considered the father of modern day genetics

mendel

passing if traits from parents to offspring is called

heredity

this trait will always show up if the allele for this trait is present

dominant

if two different alleles for a trait are present the item is considered

heterozygous

incomplete

color is mixed

codominant

2 colors show up

if an organism has 2 identical alleles for a trait it is said to be

homozygous

if an organism has 2 different alleles for a trait it is said to be

heterozygous

a chart that shows all the possible genetic outcomes of a cross is a

punnet square

when alleles are not dominant or recessive. both alleles are expressed in the subject

codominant

when one allele only partially dominated over the other, this is called

incomplete

genes found on the x and y chromosomes are

sex genes

a person who has an allele for a disease but does not show symptoms of the disease

carrier

hemophilia, sickle cell and cystic fibrosis are considered

genetic disorders/mutations

what is composed mostly of dna

chromosomes

what’s made up of four different nitrogen bases and is shaped like a twisted ladder

double helix

what are the physical traits displayed in an organism

phenotypes

what are the genes found in an organism

genotype

DD

homozygous dominant

Dd

heterozygous

dd

homozygous recessive

characteristics of life (rrrgents)

r-respiration- produces energy, r- regulation, r-reproduction g-growth and repair, e-excretion- remove metabolic waste, n-nutrition, t- transport, s- synthesis- to build from small to large

adhesion

waters natural ability to stick to other surfaces

cohesion

waters natural ability to stick to itself

3 biological molecules (food)

fats, oils, and lipids

what are enzymes and what do they do

biological catalysts that speed up reactions in the body

important organelles

mitochondria- power house, nucleus- store cells dna, ribosomes- assemble proteins, lysosomes- rid cells of waste product

mitosis

replicated chromosomes are separated into 2 new nuclei

stages of mitosis (pmatc)

prophase-the first stage of division, metaphase- chromosomes go to middle, anaphase- chromosomes go away from middle, telophase- the effects of prophase in metaphase are reversed, cytokines- forms 2 daughter cells

basic formula for photosynthesis

6co2+6h20+ light energy= c6h1206+602