Eukaryotic Cell Structures: Walls, Glycocalyx, Cytoskeleton
Eukaryotic Cell Structures
Plant Cell Wall
Functions:
- Provides rigidity and contributes to the maintenance of cell shape.
- Links adjacent cells.
- Enables the exchange of fluids and intercellular communication.
- Allows the plant cell to live in a hypotonic medium, preventing bursting.
- Waterproofs plant surface tissue.
- Serves as a protective barrier against pathogens.
Structure and Composition:
Composed of cellulose and polysaccharides (pectin and hemicellulose). Layers are:
- Lamella Media (outermost layer): Consists
Population Ecology: Dispersion, Demography, and Growth
Population Ecology: Key Concepts
- Dispersal is the movement of individuals or gametes away from centers of high population density or from their area of origin.
- Endemic species are those that are only found in a small, specific area.
- Species transplants include organisms that are intentionally or accidentally relocated from their original distribution.
-
If a transplant is successful, it indicates that the potential range of a species is larger than its actual range.
- Guppy populations evolve rapidly
VO2 Max, Muscle Contraction, and Energy Systems
Factors Influencing VO2 Max
Several factors determine a person’s maximum oxygen consumption (VO2 max):
- Inheritance
- Muscle mass
- Age
- Sex
- Training level
- Motivation
Basic Formula for VO2 During Exercise
VO2 = Vs x HR x (a-v)O2 difference
- VO2: Oxygen consumed by cells
- Vs: Systolic volume
- HR: Heart rate
- (a-v)O2 difference: Arteriovenous oxygen difference
Gas Exchange and Dead Space
Underlying Physical Process of Gas Exchange
Diffusion in gas exchange.
Respiratory Dead Space
The respiratory system contains a volume of air
Read MoreUnderstanding DNA: Structure, Function, and Genetics
Understanding DNA: The Building Block of Life
DNA is the fundamental molecule of life. The cell is the basic unit of a living organism, capable of independent function. Despite the diversity in appearance and function among living beings, all cells contain information encoded in DNA molecules. This information guides cellular activity and ensures reproduction and the transmission of traits to offspring (inheritance).
The chemistry of living organisms is largely governed by chemical compounds composed
Read MoreMitosis and Meiosis: A Detailed Comparison
Mitosis and Meiosis: A Comparison
In both mitosis and meiosis, chromosomes are duplicated only once, in the preceding interphase. Mitosis involves one division of the nucleus, accompanied by cytokinesis, producing two diploid cells. Meiosis involves two nuclear and cytoplasmic divisions, producing four haploid cells. All events specific to meiosis occur during meiosis I. Homologous chromosomes pair up to form duplicated tetrads, and crossing-over occurs. In metaphase I, the tetrads are aligned on
Read MoreHemoglobin Dissociation, Hemostasis, and EPO Factors
Hemoglobin Dissociation Curve
The oxygen-hemoglobin dissociation curve is a graphical representation of the progressive increase that occurs in the percentage of hemoglobin combined with O2 as blood O2 partial pressure (PO2) increases. This is referred to as the saturation of Hb.
Blood leaving the lungs has a PO2 of 95 mmHg and a saturation of 97%, while venous blood has a PO2 of 40 mmHg and a saturation of 75%.
Normal human blood contains 15g Hb/100ml of blood, and each gram of Hb can bind 1.34 ml
Read More