BB1720 cells, hereditary, genes Flashcards
What is a cell?
cells are the smallest unit of a living organism
How do cells work?
each cell takes matter from its surroundings to perform different chemical reactions, to survive and divide.
How do parts of a cell differentiate?
different parts of each cell have different chemical environments.
What’s the difference between individual cells in an organism?
cells differ in size, shape and response depending on their age, location and external stimuli.
What is genetics?
the study of genes, the genome and inheritance
What are genes?
the segment of a DNA sequence that codes for one specific, functional protein.
What is asexual reproduction?
the process by which the division of the cell forms two identical daughter cells
What is sexual reproduction?
the fusion of two gametes to form a zygote
What are the advantages of sexual reproduction?
greater diversity and a higher chance of survival
What are the advantages of asexual reproduction?
- has the ability to rapidly increase a population
- only requires one parent
more time and energy efficient
What are the disadvantages of sexual reproduction?
- takes more time
- favourable genetics may not be passed onto offspring
- fewer offspring produced
What are the disadvantages of asexual reproduction?
- no variation in a population
- disease could affect whole population
Which organisms produce sexually?
multicellular organisms
How do human cells reproduce?
asexually
Who is Gregor Mendel?
a scientist that studied inheritance through breeding pea plants by breeding true and cross breeding
his first discovery was published in 1866
What was Gregor Mendel’s discovery?
- Gametes are haploid and the zygote inherits equal alleles from each parent.
- Each organism carries two alleles for each gene which are either heterozygous or homozygous
What is homozygous?
a diploid contains two identical alleles of a gene.
What is heterozygous?
a diploid contains two different allels of a gene.
Why is it important to distinguish which genes are heterozygous and which are homozygous?
several genetic diseases occur due to a dominant or recessive allele.
What is codominance?
no allele can block the expression of the other allele, therefore both alleles are expressed.
What is incomplete dominance?
a dominant allele doesnt completely mask the effects of a recessive allele, therefore a mixture of the alleles in the genotype is expressed.
What is a common feature of cells?
All cells are hereditary
How can cells replicate their hereditary DNA
through template polymerisation
What does it mean for a cell to be hereditary?
their physical and mental characteristics are passed down generationally through DNA during cell division
Why is protein synthesis important?
DNA is made into functioning proteins for specific chemical reactions.
What are the 2 steps of protein synthesis?
transcription
translation
What is the importance of transcription?
segments of DNA are used as templates to synthesise RNA - to make different types of RNA. mRNA (makes proteins), catalytic RNA (break and forms covalent bonds in RNA) and structural RNA.
What is the importance of translation?
mRNA directs the synthesis of polypeptides to form proteins
Where are proteins modified in a cell?
cytoplasm, Golgi, mitochondria, rough endoplasmic reticulum and trans-Golgi network.
Where are proteins made in a cell?
cytoplasm, the mitochondria and the rough endoplasmic reticulum.
which organelles in a cell have a double membrane?
mitochondria
nucleus
Which organelle(s) in a cell contains DNA?
mitochondria
nucelus
Where are proteins made in the cell?
cytoplasm
mitochondria
rough endoplasmic reticulum
Where are proteins modified in a cell?
cytoplasm
golgi
mitochondria
rough endoplasmic reticulum
trans golgi network
features of mitochondria?
power plant of the cell
produce atp
were once bacteria
