Midterm 2 Flashcards
Homologous chromosomes
The two chromosomes make up math pair in diploid cell. Homologous chromosomes of the same length, centromere position, and staining pattern, possess genes for the same characters at corresponding loci. One homologous chromosome is inherited from the organism’s father, the other from the mother.
They are at the locus, usually can be;
Different Alleles
- Dominant B
- Recessive b
Homozygous
An organism that has two identical alleles for a gene is said to be homozygous for that gene.
Heterozygous
An organism that has two different alleles for a gene is said to be heterozygous for that gene.
Genotypes
Genetic make up (eg. PP,Pp,pp)
Who or what was Mandel?
Was the first to link patterns of inheritance to the combination of discrete units (later known as genes)
Why does genes exist and has to be with alleles and genotypes?
Genes exist as pairs and type of allele pairing having as a result the genotype.
Inheritance is involve in what?
Involves in the segregation and recombination of alleles.
Phenotype
Observable traits (eg. purple or white flowers)
How is a heritable feature called?
It’s called Character
How is it called each variant of a character?
It’s called Trait.
When does segregation occurs?
Occurs during Meiosis
When does recombination occurs?
Occurs during Fertilization
What does Cell Division results?
Results in daughter cells identical to the parent.
division = reproduction
In single celled organisms
When does division = growth / replacement?
In multicellular organisms
What should happen before division?
the chromosome/s must be replicated
Main distinctions between Binary fission and Mitosis
Binary fission primarily occurs in Prokaryotes (bacteria), while on Mitosis occurs in Eukaryotes (plant and animal cells).
Mitotic Spindle Structure
Ensures that all chromosomes are correctly divided.
During Interphase
The cell grows and makes a copy of its DNA.
During Mitotic Phase
The cell separates its DNA into two sets and divides its cytoplasm, forming two new cells.
During Mitosis
A Eukaryotic cell nucleus splits in two, followed by division of the parent cell into two daughter cells.
Stages of the cell cycle
G1 - Growth (increase in size)
S - DNA Synthesis (copies its DNA)
G2 - Growth and preparation (prepares to divide)
M - Mitosis (and divides)
Diploidy
The presence of two complete sets of chromosomes in an organism’s cells, with each parent contributing a chromosome to each pair.
23 haploid
Chromosomes are known as the sex chromosomes. Male and female have 23 chromosomes.
46 diploid
Is the total chromosomes, half come from the mother, the other half from the father.
44+2
humans would deviate from the current state of human DNA which contains 44 = autosomes, and 2 = sex chromosomes.
What happens during cancer?
the cell cycle is dysregulated, due to mutations.
What is a Generic disease?
occur when a mutation (a harmful change to a gene, also known as a pathogenic variant) affects your genes or when you have the wrong amount of genetic material. (E.g Down Syndrome).
What is a Inherited disease?
Conditions in which the genetic changes are almost exclusively responsible for causing the condition. (E.g. spinal muscular atrophy).
What are the basic function of meiosis?
The basic function is to produce two identical daughter cells with exactly the same complement of chromosomes.
What does Sexual reproduction do?
generates and maintains genetic variability in the population.
Contrasts of mitosis and meiosis
Mitosis produces two genetically identical “daughter” cells from a single “parent” cell, whereas meiosis produces cells that are genetically unique from the parent and contain only half as much DNA. (See your Notebook)
Why are you a combination of your parents?
Because each of my parents give half of their genes to me
Why are you not identical to your siblings (if you have them)?
We only share 50% of DNA and not because we have the same parents that means we are identical, we have different genomes. Different egg cell and sperm>
Why might you be more genetically similar to one grandparent than another?
Because they can affect genes and that can be pass down into our genes.
Why are your chromosomes probably not identical to your parent’s chromosomes?
I only have chromosomes from both of them but that doesn’t mean they would be identical, my chromosomes come or genes are only half that come from my parents .
meiosis and the patterns of inheritance described by Mendel are linked
genes are inherited as pairs of alleles that behave in a dominant and recessive pattern.
What happens to Cells during cell division?
Cells live and grow between rounds of cell division..
- the outer membrane increasingly pinches inward until the new cells that are forming separate from each other. This process typically produces two new (daughter) cells from one (parent) cell. During cell division, the contents of the parent cell are copied and divided between the two daughter cells
Dysregulated mitosis is what?
is the common feature of all cancers.
What is replications and what happens?
Is the synthesis of an identical copy of the chromosome or chromosomes. It occurs during the life of the cell prior to cell division.
Homologous chromosomes are the same as replicated chromosomes?
There not the same.
What are the differences between homologous chromosomes and replicated chromosomes?
There may be variation between them, resulting in different alleles in combinations.
Different versions of the same gene:
Are said to be different alleles.
may or may not carry different alleles at the same gene locus.
Homologous chromosomes
Genetic variability
created by sexual reproduction is key to populations and evolution.
Composition of Nucleic acids
A sugar or derivative of a sugar (ribose or 2-deoxyribose), a nucleobase (cytosine, guanine, adenine, thymine, or uracil), and phosphoric aci
What is the composition of the Nucleic acids of DNA and RNA?
Both DNA and RNA are made from nucleotides, each containing a five-carbon sugar backbone, a phosphate group, and a nitrogen base
the structure of the DNA molecule (double helix)
f two linked strands that wind around each other to resemble a twisted ladder in a helix-like shape. Each strand has a backbone made of alternating sugar (deoxyribose) and phosphate groups. Attached to each sugar is one of four bases: adenine (A), cytosine (C), guanine (G) or thymine (T).
complementary base pairing, and which nucleotides basepair:
thymine being paired with adenine and cytosine paired with guanine.
How does the structure of DNA facilitate the passing down of information from one generation of cells to the next?
The ability of each strand of a DNA molecule to act as a template for producing a complementary strand enables a cell to copy, or replicate, its genes before passing them on to its descendants.
the flow of genetic information from DNA to RNA to protein
The flow of information from DNA to RNA to proteins is one of the fundamental principles of molecular biology. It is so important that it is sometimes called the “central dogma.” Through the processes of transcription and translation, information from genes is used to make proteins.
Replication
Occurs in the nucleus and duplicates a full strand of DNA.
Transcription
Happens in the nucleus and use a strand of DNA to build a molecule of MRNA.
Translation
Happens in the cytoplasm and uses mRNA to build an amino acid chain. (it is ribosomes that translate the RNA transcript into a protein)
difference between replication, transcription and translation:
Replication creates identical DNA strands, while transcription converts DNA into messenger RNA (mRNA). Translation then decodes mRNA into amino acids, forming proteins essential for life functions.
Genes
are special regions within the DNA molecule.
What can be transcribed and translated.?
Only gene regions::
What a codon is?
A codon is a DNA or RNA sequence of three nucleotides (a trinucleotide) that forms a unit of genomic information encoding a particular amino acid or signaling the termination of protein synthesis (stop signals). There are 64 different codons: 61 specify amino acids and 3 are used as stop signals.
Mutations
changes in the DNA structure.
What is mutation?
a change in the DNA sequence of an organism.
Mutations may or may not led to:
Changes in protein structure or expression.
Different forms of energy
- kinetic
- chemical
- potential
- heat
kinetic energy
the energy an object has because of its motion
Chemical energy
the energy which is stored in the bonds of chemical compounds (molecules and atoms).
Potential energy
energy that is stored in an object due to its position or condition.
Heat energy
The transfer or flow due to the difference in temperature between the two objects is called heat.(an ice cube has heat energy and so does a glass of lemonade)
Theory of energy
energy can change form but cannot be created or destroyed, and some energy is lost as heat, which is the least useful form of energy for cells.
What are exergonic reactions?
is a chemical reaction where the change in the free energy is negative (there is a net release of free energy).
What are endergonic reactions?
is a chemical reaction in which the standard change in free energy is positive, and an additional driving force is needed to perform this reaction.
How ATP couple exergonic and endergonic reactions?
provides the energy for both energy-consuming endergonic reactions and energy-releasing exergonic reactions,
How photosynthesis and respiration are linked?
Photosynthesis makes glucose which is used in cellular respiration for making ATP.
What occurs during glycolysis?
glucose is broken down into two pyruvate molecules.
What occurs during the citric acid cycle?
metabolizes acetate derived from carbohydrates, proteins, and fats to form adenosine triphosphate (ATP)
What occurs during oxidative phosphorylation?
electrons derived from NADH and FADH2 combine with O2, and the energy released from these oxidation/ reduction reactions is used to drive the synthesis of ATP from ADP.
How glycolysis, the citric acid cycle and oxidative phosphorylation are involved in the making of ATP?
cellular respiration: glycolysis, the citric acid cycle, and oxidative phosphorylation. Glycolysis takes place in the cytosol, the citric acid cycle occurs in the mitochondrial matrix, and oxidative phosphorylation occurs on the inner mitochondrial membrane.
