Nervous System and Genetics Flashcards

Practice flashcards covering the Nervous System, DNA replication, Mutations, Biotechnology, and Evolutionary Genetics as described in the lecture notes.

The _________ nervous system consists of the brain and the spinal chord.

central

The _________ nervous system controls skeletal muscles and functions for voluntary movements.

Somatic

The _________ nervous system controls internal organs and glands involuntarily to maintain homeostasis.

autonomic

The _________ system prepares the body for 'fight or flight' by increasing heart rate and dilating bronchioles.

sympathetic

The _________ system promotes 'rest and digest' and has an antagonistic effect to the sympathetic system.

parasympathetic

In the regulation of $CO_2$ concentration, signals are sent to the respiratory centre in the _________ to change breathing rates.

medulla

The _________ provides a large surface area for receiving information from other neurons through synaptic transmission.

Dendrites

The _________ is the part of the cell body where post-synaptic potentials are summated to determine if an action potential is triggered.

axon hillock

Electrical impulses jump from node to node in a process called _________ conduction to speed up transmission down the axon.

Salutatory

The _________ _________ supports the electrical impulse, provides nutrients, and insulates the axon.

myelin sheath

During synaptic transmission, the entry of _________ into the presynaptic neuron causes vesicles to fuse with the membrane.

$$Ca^{2+}$$

In the _________ phase of an action potential, the inside of the axon becomes more positive compared to the outside due to $Na^+$ movement.

Depolarization

A _________ mutation changes the DNA sequence so that the mRNA codon codes for a premature 'stop' codon.

non-sense

Insertion and deletion mutations cause a _________ mutation, which changes every amino acid positioned after the mutation.

frame shift

The CRISPR tool uses _________ as molecular scissors to cut DNA at a specific location.

cas9

In DNA replication, the enzyme _________ unzips the double helix by breaking hydrogen bonds.

helicase

The enzyme _________ _________ builds the new DNA strand by moving $3'$ to $5'$ along the template strand.

DNA Polymerase

_________ dominance occurs when the phenotype of a heterozygous individual is exactly in between the two homozygous phenotypes.

Incomplete

In _________, both alleles are expressed equally, such as a white flower having red spots.

codominance

A _________ individual carries a recessive trait but does not express the physical phenotype of that trait.

carrier

In gel electrophoresis, DNA molecules move toward the _________ electrode because DNA is negatively charged.

positive

In the _________ step of PCR, the DNA sample is heated at $98\,^{\circ}\text{C}$ to separate the strands.

Denaturing

The second step of PCR, called _________, involves cooling the sample to $60\,^{\circ}\text{C}$ so primers can bond to the strands.

Annealing

A standard dihybrid cross between two heterozygous individuals results in a phenotypic ratio of _________.

$$9:3:3:1$$

_________ is an interaction where one gene affects the expression of another gene, such as coat color in Labradors.

Epistasis

Phenotypes like skin color and height that display a smooth spectrum of variation are examples of _________ inheritance.

polygenic

_________ is the condition where the chromosome number is not an exact multiple of the normal haploid set, such as in Down Syndrome.

Aneuploidy

The failure of homologous chromosomes or chromatids to separate correctly during cell division is called _________.

nondisjunction

_________ speciation occurs when a population becomes isolated geographically and undergoes genetic divergence.

Allopatric

The _________ effect occurs when a small subset of a population arrives in a new habitat, carrying only a small portion of the original alleles.

founder

Individuals with the heterozygous genotype for sickle cell anemia have a higher resistance to _________.

Malaria